support transformers with an unknown number of outputs

To support different types of nodes in the build graph, we introduce
the base class BuildGraphNode. Artifact now derives from BuildGraphNode.
A RuleNode class is introduced that represents a rule in the build graph.
Rules are applied in the build phase and not in a pre-build phase
anymore.
The handling of moc has been revisited. The fixed automoc pre-build
phase is no more.

This is the squashed merge of a feature branch.

Task-number: QBS-370
Change-Id: If27cdc51cba8c9542e4282c2caa456faa723aeff
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>

68 files changed, 2699 insertions, 1232 deletions

diff --git a/doc/reference/items/rule.qdoc b/doc/reference/items/rule.qdoc
index 35fc2aa5e..05fc22643 100644
--- a/doc/reference/items/rule.qdoc
+++ b/doc/reference/items/rule.qdoc
@@ -116,6 +116,13 @@
             Unlike \a{inputs}, the property \a{auxiliaryInputs} has no effect on the content of the
             \a{inputs} variable in the \a{prepare} script.
     \row
+        \li excludedAuxiliaryInputs
+        \li string list
+        \li undefined
+        \li A list of file tags. Connections to rules that produce these file tags are prevented.
+            This property has no effect on the content of the \a{inputs} variable in the \a{prepare}
+            script.
+    \row
         \li usings
         \li string list
         \li undefined
@@ -131,6 +138,28 @@
            script. Also, each output artifact of this rule will be dependent on
            those artifacts.
     \row
+        \li outputArtifacts
+        \li array of objects
+        \li undefined
+        \li An array of output artifacts, specified as JavaScript objects.
+            Example:
+            \code
+            outputArtifacts: [{filePath: "myfile.txt", fileTags: ["foo", "bar"]}]
+            \endcode
+            For a description of the possible properties, see the documentation of the Artifact
+            item.
+            Output artifacts can be specified either by \c{Rule.outputArtifacts} or by \c{Artifact}
+            items. Use \c{Rule.outputArtifacts} if the set of outputs is not fixed but dependent on
+            the input's content.
+            The user may set the property \c{explicitlyDependsOn} on artifact objects, which is
+            similar to \c{Rule.explicitlyDependsOn}.
+    \row
+        \li outputFileTags
+        \li string list
+        \li undefined
+        \li If output artifacts are specified by \c{Rule.outputArtifacts}, then
+            \c{Rule.outputFileTags} must be a list of file tags the rule potentially produces.
+    \row
         \li condition
         \li bool
         \li true
diff --git a/src/lib/corelib/api/project.cpp b/src/lib/corelib/api/project.cpp
index b9e9b4583..99b2eeac0 100644
--- a/src/lib/corelib/api/project.cpp
+++ b/src/lib/corelib/api/project.cpp
@@ -438,18 +438,10 @@ void ProjectPrivate::addFiles(const ProductData &product, const GroupData &group
         groupContext.resolvedGroup->files << artifact;
     }
     if (groupContext.resolvedProduct->enabled) {
-        ArtifactsPerFileTagMap artifactsPerFileTag;
         foreach (const SourceArtifactConstPtr &sa, addedSourceArtifacts) {
             Artifact * const artifact = createArtifact(groupContext.resolvedProduct, sa, logger);
-            foreach (const FileTag &ft, artifact->fileTags)
-                artifactsPerFileTag[ft] += artifact;
+            groupContext.resolvedProduct->registerAddedArtifact(artifact);
         }
-        RulesEvaluationContextPtr &evalContext
-                = groupContext.resolvedProduct->topLevelProject()->buildData->evaluationContext;
-        evalContext = QSharedPointer<RulesEvaluationContext>(new RulesEvaluationContext(logger));
-        RulesApplicator(groupContext.resolvedProduct, artifactsPerFileTag, logger).applyAllRules();
-        addTargetArtifacts(groupContext.resolvedProduct, artifactsPerFileTag, logger);
-        evalContext.clear();
     }
     doSanityChecks(internalProject, logger);
     groupContext.currentGroup.d->filePaths << filesContext.absoluteFilePaths;
@@ -521,14 +513,10 @@ void ProjectPrivate::removeFilesFromBuildGraph(const ResolvedProductConstPtr &pr
     QBS_CHECK(internalProject->buildData);
     foreach (const SourceArtifactPtr &sa, files) {
         Artifact * const artifact = lookupArtifact(product, sa->absoluteFilePath);
-        QBS_CHECK(artifact);
-        internalProject->buildData->removeArtifactAndExclusiveDependents(artifact, logger);
+        if (artifact) // Can be null if the executor has not yet applied the respective rule.
+            internalProject->buildData->removeArtifactAndExclusiveDependents(artifact, logger);
+        delete artifact;
     }
-    RulesEvaluationContextPtr &evalContext
-            = internalProject->buildData->evaluationContext;
-    evalContext = QSharedPointer<RulesEvaluationContext>(new RulesEvaluationContext(logger));
-    internalProject->buildData->updateNodesThatMustGetNewTransformer(logger);
-    evalContext.clear();
 }
 
 static void updateLocationIfNecessary(CodeLocation &location, const CodeLocation &changeLocation,
@@ -611,7 +599,7 @@ void ProjectPrivate::retrieveProjectData(ProjectData &projectData,
             product.d->groups << createGroupDataFromGroup(resolvedGroup);
         if (resolvedProduct->enabled) {
             QBS_CHECK(resolvedProduct->buildData);
-            foreach (const Artifact * const a, resolvedProduct->buildData->targetArtifacts) {
+            foreach (const Artifact * const a, resolvedProduct->buildData->targetArtifacts()) {
                 TargetArtifact ta;
                 ta.d->filePath = a->filePath();
                 ta.d->fileTags = a->fileTags.toStringList();
@@ -864,7 +852,8 @@ QList<InstallableFile> Project::installableFilesForProduct(const ProductData &pr
     }
     if (internalProduct->enabled) {
         QBS_CHECK(internalProduct->buildData);
-        foreach (const Artifact * const artifact, internalProduct->buildData->artifacts) {
+        foreach (const Artifact * const artifact,
+                 ArtifactSet::fromNodeSet(internalProduct->buildData->nodes)) {
             if (artifact->artifactType == Artifact::SourceFile)
                 continue;
             InstallableFile f;
diff --git a/src/lib/corelib/buildgraph/artifact.cpp b/src/lib/corelib/buildgraph/artifact.cpp
index c5203e5ea..d9f442494 100644
--- a/src/lib/corelib/buildgraph/artifact.cpp
+++ b/src/lib/corelib/buildgraph/artifact.cpp
@@ -30,7 +30,7 @@
 #include "artifact.h"
 
 #include "transformer.h"
-
+#include "buildgraphvisitor.h"
 #include <language/propertymapinternal.h>
 #include <tools/fileinfo.h>
 #include <tools/persistence.h>
@@ -62,6 +62,19 @@ Artifact::Artifact()
 
 Artifact::~Artifact()
 {
+    foreach (Artifact *p, parentArtifacts())
+        p->childrenAddedByScanner.remove(this);
+}
+
+void Artifact::accept(BuildGraphVisitor *visitor)
+{
+    if (visitor->visit(this))
+        acceptChildren(visitor);
+}
+
+QString Artifact::toString() const
+{
+    return QLatin1String("ARTIFACT ") + filePath();
 }
 
 void Artifact::initialize()
@@ -71,15 +84,35 @@ void Artifact::initialize()
     inputsScanned = false;
     timestampRetrieved = false;
     alwaysUpdated = true;
+    oldDataPossiblyPresent = true;
+}
+
+ArtifactSet Artifact::parentArtifacts() const
+{
+    return ArtifactSet::fromNodeSet(parents);
+}
+
+ArtifactSet Artifact::childArtifacts() const
+{
+    return ArtifactSet::fromNodeSet(children);
+}
+
+void Artifact::onChildDisconnected(BuildGraphNode *child)
+{
+    Artifact *childArtifact = dynamic_cast<Artifact *>(child);
+    if (!childArtifact)
+        return;
+    childrenAddedByScanner.remove(childArtifact);
 }
 
 void Artifact::load(PersistentPool &pool)
 {
     FileResourceBase::load(pool);
-    pool.loadContainer(children);
+    BuildGraphNode::load(pool);
+    children.load(pool);
 
     // restore parents of the loaded children
-    for (ArtifactSet::const_iterator it = children.constBegin(); it != children.constEnd(); ++it)
+    for (NodeSet::const_iterator it = children.constBegin(); it != children.constEnd(); ++it)
         (*it)->parents.insert(this);
 
     pool.loadContainer(childrenAddedByScanner);
@@ -90,16 +123,18 @@ void Artifact::load(PersistentPool &pool)
     pool.stream()
             >> fileTags
             >> artifactType
-            >> autoMocTimestamp
             >> c;
     alwaysUpdated = c;
+    pool.stream() >> c;
+    oldDataPossiblyPresent = c;
 }
 
 void Artifact::store(PersistentPool &pool) const
 {
     FileResourceBase::store(pool);
+    BuildGraphNode::store(pool);
     // Do not store parents to avoid recursion.
-    pool.storeContainer(children);
+    children.store(pool);
     pool.storeContainer(childrenAddedByScanner);
     pool.storeContainer(fileDependencies);
     pool.store(properties);
@@ -107,8 +142,8 @@ void Artifact::store(PersistentPool &pool) const
     pool.stream()
             << fileTags
             << artifactType
-            << autoMocTimestamp
-            << static_cast<unsigned char>(alwaysUpdated);
+            << static_cast<unsigned char>(alwaysUpdated)
+            << static_cast<unsigned char>(oldDataPossiblyPresent);
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/artifact.h b/src/lib/corelib/buildgraph/artifact.h
index 93cfeec52..ca62daea7 100644
--- a/src/lib/corelib/buildgraph/artifact.h
+++ b/src/lib/corelib/buildgraph/artifact.h
@@ -32,12 +32,10 @@
 
 #include "artifactset.h"
 #include "filedependency.h"
+#include "buildgraphnode.h"
 #include "forward_decls.h"
 #include <language/filetags.h>
-#include <language/forward_decls.h>
 #include <tools/filetime.h>
-#include <tools/persistentobject.h>
-#include <tools/weakpointer.h>
 
 #include <QSet>
 #include <QString>
@@ -54,18 +52,19 @@ class Logger;
  *
  *
  */
-class Artifact : public FileResourceBase
+class Artifact : public FileResourceBase, public BuildGraphNode
 {
 public:
     Artifact();
     ~Artifact();
 
-    ArtifactSet parents;
-    ArtifactSet children;
+    Type type() const { return ArtifactNodeType; }
+    void accept(BuildGraphVisitor *visitor);
+    QString toString() const;
+
     ArtifactSet childrenAddedByScanner;
     QSet<FileDependency *> fileDependencies;
     FileTags fileTags;
-    WeakPointer<ResolvedProduct> product;
     TransformerPtr transformer;
     PropertyMapPtr properties;
 
@@ -76,22 +75,16 @@ public:
         Generated = 4
     };
 
-    enum BuildState
-    {
-        Untouched = 0,
-        Buildable,
-        Building,
-        Built
-    };
-
     ArtifactType artifactType;
-    FileTime autoMocTimestamp;
-    BuildState buildState;                  // Do not serialize. Will be refreshed for every build.
     bool inputsScanned : 1;                 // Do not serialize. Will be refreshed for every build.
     bool timestampRetrieved : 1;            // Do not serialize. Will be refreshed for every build.
     bool alwaysUpdated : 1;
+    bool oldDataPossiblyPresent : 1;
 
     void initialize();
+    ArtifactSet parentArtifacts() const;
+    ArtifactSet childArtifacts() const;
+    void onChildDisconnected(BuildGraphNode *child);
 
 private:
     void load(PersistentPool &pool);
@@ -113,16 +106,16 @@ inline QString toString(Artifact::ArtifactType t)
 }
 
 // debugging helper
-inline QString toString(Artifact::BuildState s)
+inline QString toString(BuildGraphNode::BuildState s)
 {
     switch (s) {
-    case Artifact::Untouched:
+    case BuildGraphNode::Untouched:
         return QLatin1String("Untouched");
-    case Artifact::Buildable:
+    case BuildGraphNode::Buildable:
         return QLatin1String("Buildable");
-    case Artifact::Building:
+    case BuildGraphNode::Building:
         return QLatin1String("Building");
-    case Artifact::Built:
+    case BuildGraphNode::Built:
         return QLatin1String("Built");
     default:
         return QLatin1String("Unknown");
diff --git a/src/lib/corelib/buildgraph/artifactcleaner.cpp b/src/lib/corelib/buildgraph/artifactcleaner.cpp
index a1e91cdaf..ad93c1d4a 100644
--- a/src/lib/corelib/buildgraph/artifactcleaner.cpp
+++ b/src/lib/corelib/buildgraph/artifactcleaner.cpp
@@ -113,7 +113,7 @@ private:
         if (m_options.cleanType() == CleanOptions::CleanupTemporaries) {
             QBS_CHECK(artifact->transformer);
             foreach (Artifact * const sibling, artifact->transformer->outputs) {
-                if (artifact->product->buildData->targetArtifacts.contains(sibling))
+                if (artifact->product->buildData->targetArtifacts().contains(sibling))
                     return;
             }
         }
diff --git a/src/lib/corelib/buildgraph/artifactset.cpp b/src/lib/corelib/buildgraph/artifactset.cpp
index 921de6ee0..c44f5e4b9 100644
--- a/src/lib/corelib/buildgraph/artifactset.cpp
+++ b/src/lib/corelib/buildgraph/artifactset.cpp
@@ -28,30 +28,44 @@
 ****************************************************************************/
 
 #include "artifactset.h"
+#include "artifact.h"
 
 namespace qbs {
 namespace Internal {
 
 ArtifactSet::ArtifactSet()
-{}
+{
+}
 
 ArtifactSet::ArtifactSet(const ArtifactSet &other)
-    : m_data(other.m_data)
-{}
+    : QSet<Artifact *>(other)
+{
+}
+
+ArtifactSet::ArtifactSet(const QSet<Artifact *> &other)
+    : QSet<Artifact *>(other)
+{
+}
 
-ArtifactSet &ArtifactSet::unite(const ArtifactSet &other)
+ArtifactSet ArtifactSet::fromNodeSet(const NodeSet &nodes)
 {
-    std::set<Artifact *>::const_iterator it = other.m_data.begin();
-    for (; it != other.m_data.end(); ++it)
-        m_data.insert(*it);
-    return *this;
+    ArtifactSet result;
+    result.reserve(nodes.count());
+    foreach (BuildGraphNode *node, nodes) {
+        Artifact *artifact = dynamic_cast<Artifact *>(node);
+        if (artifact)
+            result += artifact;
+    }
+    return result;
 }
 
-void ArtifactSet::remove(Artifact *artifact)
+ArtifactSet ArtifactSet::fromNodeList(const QList<Artifact *> &lst)
 {
-    iterator it = m_data.find(artifact);
-    if (it != m_data.end())
-        m_data.erase(it);
+    ArtifactSet result;
+    result.reserve(lst.count());
+    for (QList<Artifact *>::const_iterator it = lst.constBegin(); it != lst.end(); ++it)
+        result.insert(*it);
+    return result;
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/artifactset.h b/src/lib/corelib/buildgraph/artifactset.h
index fccff34d9..092e9e8a2 100644
--- a/src/lib/corelib/buildgraph/artifactset.h
+++ b/src/lib/corelib/buildgraph/artifactset.h
@@ -30,80 +30,22 @@
 #ifndef QBS_ARTIFACTSET_H
 #define QBS_ARTIFACTSET_H
 
-#include <set>
-#include <cstddef>
+#include <QSet>
 
 namespace qbs {
 namespace Internal {
 
 class Artifact;
+class NodeSet;
 
-/**
-  * Set that holds a bunch of build graph artifacts.
-  * This is faster than QSet when iterating over the container.
-  */
-class ArtifactSet
+class ArtifactSet : public QSet<Artifact *>
 {
 public:
     ArtifactSet();
     ArtifactSet(const ArtifactSet &other);
-
-    ArtifactSet &unite(const ArtifactSet &other);
-
-    typedef std::set<Artifact *>::const_iterator const_iterator;
-    typedef std::set<Artifact *>::iterator iterator;
-    typedef Artifact * value_type;
-
-    iterator begin() { return m_data.begin(); }
-    iterator end() { return m_data.end(); }
-    const_iterator begin() const { return m_data.begin(); }
-    const_iterator end() const { return m_data.end(); }
-    const_iterator constBegin() const { return m_data.begin(); }
-    const_iterator constEnd() const { return m_data.end(); }
-
-    void insert(Artifact *artifact)
-    {
-        m_data.insert(artifact);
-    }
-
-    void operator +=(Artifact *artifact)
-    {
-        insert(artifact);
-    }
-
-    void remove(Artifact *artifact);
-
-    bool contains(Artifact *artifact) const
-    {
-        return m_data.find(artifact) != m_data.end();
-    }
-
-    void clear()
-    {
-        m_data.clear();
-    }
-
-    bool isEmpty() const
-    {
-        return m_data.empty();
-    }
-
-    int count() const
-    {
-        return (int)m_data.size();
-    }
-
-    void reserve(int)
-    {
-        // no-op
-    }
-
-    bool operator==(const ArtifactSet &other) const { return m_data == other.m_data; }
-    bool operator!=(const ArtifactSet &other) const { return !(*this == other); }
-
-
-private:
-    std::set<Artifact *> m_data;
+    ArtifactSet(const QSet<Artifact *> &other);
+    static ArtifactSet fromNodeSet(const NodeSet &nodes);
+    static ArtifactSet fromNodeList(const QList<Artifact *> &lst);
 };
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/artifactvisitor.cpp b/src/lib/corelib/buildgraph/artifactvisitor.cpp
index 3b5203e26..e8f438c9b 100644
--- a/src/lib/corelib/buildgraph/artifactvisitor.cpp
+++ b/src/lib/corelib/buildgraph/artifactvisitor.cpp
@@ -40,27 +40,26 @@ ArtifactVisitor::ArtifactVisitor(int artifactType) : m_artifactType(artifactType
 {
 }
 
-void ArtifactVisitor::visitArtifact(Artifact *artifact)
-{
-    QBS_CHECK(artifact);
-    if (m_artifactType & artifact->artifactType)
-        doVisit(artifact);
-}
-
 void ArtifactVisitor::visitProduct(const ResolvedProductConstPtr &product)
 {
     if (!product->buildData)
         return;
-    foreach (Artifact * const artifact, product->buildData->artifacts)
-        visitArtifact(artifact);
+    foreach (BuildGraphNode *node, product->buildData->nodes)
+        node->accept(this);
 }
 
 void ArtifactVisitor::visitProject(const ResolvedProjectConstPtr &project)
 {
-    foreach (const ResolvedProductConstPtr &product, project->products)
+    foreach (const ResolvedProductConstPtr &product, project->allProducts())
         visitProduct(product);
-    foreach (const ResolvedProjectConstPtr &subProject, project->subProjects)
-        visitProject(subProject);
+}
+
+bool ArtifactVisitor::visit(Artifact *artifact)
+{
+    QBS_CHECK(artifact);
+    if (m_artifactType & artifact->artifactType)
+        doVisit(artifact);
+    return false;
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/artifactvisitor.h b/src/lib/corelib/buildgraph/artifactvisitor.h
index 0c113ea1b..2cd67a8f8 100644
--- a/src/lib/corelib/buildgraph/artifactvisitor.h
+++ b/src/lib/corelib/buildgraph/artifactvisitor.h
@@ -31,6 +31,7 @@
 
 #include "forward_decls.h"
 
+#include "buildgraphvisitor.h"
 #include <language/forward_decls.h>
 
 #include <QList>
@@ -39,14 +40,14 @@
 namespace qbs {
 namespace Internal {
 
-class ArtifactVisitor
+class ArtifactVisitor : public BuildGraphVisitor
 {
 public:
     ArtifactVisitor(int artifactType);
 
-    virtual void visitArtifact(Artifact *artifact);
-    virtual void visitProduct(const ResolvedProductConstPtr &product);
-    virtual void visitProject(const ResolvedProjectConstPtr &project);
+    void visitProduct(const ResolvedProductConstPtr &product);
+    void visitProject(const ResolvedProjectConstPtr &project);
+    bool visit(Artifact *artifact);
 
 private:
     virtual void doVisit(Artifact *artifact) = 0;
diff --git a/src/lib/corelib/buildgraph/automoc.cpp b/src/lib/corelib/buildgraph/automoc.cpp
deleted file mode 100644
index 13c24674a..000000000
--- a/src/lib/corelib/buildgraph/automoc.cpp
+++ /dev/null
@@ -1,345 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
-** Contact: http://www.qt-project.org/legal
-**
-** This file is part of the Qt Build Suite.
-**
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and Digia.  For licensing terms and
-** conditions see http://qt.digia.com/licensing.  For further information
-** use the contact form at http://qt.digia.com/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL included in the
-** packaging of this file.  Please review the following information to
-** ensure the GNU Lesser General Public License version 2.1 requirements
-** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
-**
-** In addition, as a special exception, Digia gives you certain additional
-** rights.  These rights are described in the Digia Qt LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
-**
-****************************************************************************/
-
-#include "automoc.h"
-#include "productbuilddata.h"
-#include "projectbuilddata.h"
-#include "buildgraph.h"
-#include "rulesapplicator.h"
-#include "scanresultcache.h"
-#include <buildgraph/artifact.h>
-#include <buildgraph/transformer.h>
-#include <language/language.h>
-#include <logging/translator.h>
-#include <tools/error.h>
-#include <tools/fileinfo.h>
-#include <tools/scannerpluginmanager.h>
-
-namespace qbs {
-namespace Internal {
-
-AutoMoc::AutoMoc(const Logger &logger, QObject *parent)
-    : QObject(parent)
-    , m_scanResultCache(0)
-    , m_logger(logger)
-{
-}
-
-void AutoMoc::setScanResultCache(ScanResultCache *scanResultCache)
-{
-    m_scanResultCache = scanResultCache;
-}
-
-void AutoMoc::apply(const ResolvedProductPtr &product)
-{
-    if (cppScanners().isEmpty() || hppScanners().isEmpty())
-        throw ErrorInfo(Tr::tr("C++ scanner cannot be loaded."));
-
-    Artifact *pluginMetaDataFile = 0;
-    Artifact *pchFile = 0;
-    QList<QPair<Artifact *, FileType> > artifactsToMoc;
-    QSet<QString> includedMocCppFiles;
-    const FileTime currentTime = FileTime::currentTime();
-    ArtifactSet::const_iterator it = product->buildData->artifacts.begin();
-    for (; it != product->buildData->artifacts.end(); ++it) {
-        Artifact *artifact = *it;
-        if (!pchFile || !pluginMetaDataFile) {
-            foreach (const FileTag &fileTag, artifact->fileTags) {
-                if (fileTag == "cpp_pch")
-                    pchFile = artifact;
-                else if (fileTag == "qt_plugin_metadata")
-                    pluginMetaDataFile = artifact;
-            }
-        }
-
-        if (!pluginMetaDataFile && artifact->fileTags.contains("qt_plugin_metadata")) {
-            if (m_logger.debugEnabled()) {
-                m_logger.qbsDebug() << "[AUTOMOC] found Qt plugin metadata file "
-                                    << artifact->filePath();
-            }
-            pluginMetaDataFile = artifact;
-        }
-        if (artifact->artifactType != Artifact::SourceFile)
-            continue;
-        if (artifact->timestamp() < artifact->autoMocTimestamp)
-            continue;
-        artifact->autoMocTimestamp = currentTime;
-        const FileType fileType = AutoMoc::fileType(artifact);
-        if (fileType == UnknownFileType)
-            continue;
-        FileTag mocFileTag;
-        bool alreadyMocced = isVictimOfMoc(artifact, fileType, mocFileTag);
-        bool hasQObjectMacro;
-        scan(artifact, fileType, hasQObjectMacro, includedMocCppFiles);
-        if (hasQObjectMacro && !alreadyMocced)
-            artifactsToMoc += qMakePair(artifact, fileType);
-        else if (!hasQObjectMacro && alreadyMocced)
-            unmoc(artifact, mocFileTag);
-    }
-
-    Artifact *pluginHeaderFile = 0;
-    ArtifactsPerFileTagMap artifactsPerFileTag;
-    for (int i = artifactsToMoc.count(); --i >= 0;) {
-        const QPair<Artifact *, FileType> &p = artifactsToMoc.at(i);
-        Artifact * const artifact = p.first;
-        FileType fileType = p.second;
-        foreach (const FileTag &fileTag, artifact->fileTags) {
-            if (fileTag == "moc_hpp") {
-                const QString mocFileName = generateMocFileName(artifact, fileType);
-                if (includedMocCppFiles.contains(mocFileName)) {
-                    FileTag newFileTag = "moc_hpp_inc";
-                    artifact->fileTags -= fileTag;
-                    artifact->fileTags += newFileTag;
-                    artifactsPerFileTag[newFileTag].insert(artifact);
-                    continue;
-                }
-            } else if (fileTag == "moc_plugin_hpp") {
-                if (m_logger.debugEnabled()) {
-                    m_logger.qbsDebug() << "[AUTOMOC] found Qt plugin header file "
-                                        << artifact->filePath();
-                }
-                FileTag newFileTag = "moc_hpp";
-                artifact->fileTags -= fileTag;
-                artifact->fileTags += newFileTag;
-                artifactsPerFileTag[newFileTag].insert(artifact);
-                pluginHeaderFile = artifact;
-            }
-            artifactsPerFileTag[fileTag].insert(artifact);
-        }
-    }
-
-    if (pchFile)
-        artifactsPerFileTag["cpp_pch"] += pchFile;
-    if (!artifactsPerFileTag.isEmpty()) {
-        emit reportCommandDescription(QLatin1String("automoc"),
-                                      Tr::tr("Applying moc rules for '%1'.")
-                                      .arg(product->name));
-        RulesApplicator(product, artifactsPerFileTag, m_logger).applyAllRules();
-    }
-    if (pluginHeaderFile && pluginMetaDataFile) {
-        // Make every artifact that is dependent of the header file also
-        // dependent of the plugin metadata file.
-        foreach (Artifact *outputOfHeader, pluginHeaderFile->parents)
-            loggedConnect(outputOfHeader, pluginMetaDataFile, m_logger);
-    }
-
-    product->topLevelProject()->buildData->updateNodesThatMustGetNewTransformer(m_logger);
-}
-
-QString AutoMoc::generateMocFileName(Artifact *artifact, FileType fileType)
-{
-    QString mocFileName;
-    switch (fileType) {
-    case UnknownFileType:
-        break;
-    case HppFileType:
-        mocFileName = QLatin1String("moc_") + FileInfo::baseName(artifact->filePath()) +
-                                                                            QLatin1String(".cpp");
-        break;
-    case CppFileType:
-        mocFileName = FileInfo::baseName(artifact->filePath()) + QLatin1String(".moc");
-        break;
-    }
-    return mocFileName;
-}
-
-AutoMoc::FileType AutoMoc::fileType(Artifact *artifact)
-{
-    foreach (const FileTag &fileTag, artifact->fileTags)
-        if (fileTag == "hpp")
-            return HppFileType;
-        else if (fileTag == "cpp")
-            return CppFileType;
-    return UnknownFileType;
-}
-
-void AutoMoc::scan(Artifact *artifact, FileType fileType, bool &hasQObjectMacro,
-        QSet<QString> &includedMocCppFiles)
-{
-    if (m_logger.traceEnabled())
-        m_logger.qbsTrace() << "[AUTOMOC] checks " << relativeArtifactFileName(artifact);
-
-    hasQObjectMacro = false;
-
-    foreach (ScannerPlugin *scanner, fileType == HppFileType ? hppScanners() : cppScanners()) {
-        ScanResultCache::Result scanResult = m_scanResultCache->value(artifact->filePath());
-        if (!scanResult.valid) {
-            scanResult.valid = true;
-            void *opaq = scanner->open(artifact->filePath().utf16(),
-                                       ScanForDependenciesFlag | ScanForFileTagsFlag);
-            if (!opaq || !scanner->additionalFileTags)
-                continue;
-
-            int length = 0;
-            const char **szFileTagsFromScanner = scanner->additionalFileTags(opaq, &length);
-            if (szFileTagsFromScanner && length > 0) {
-                for (int i = length; --i >= 0;)
-                    scanResult.additionalFileTags += szFileTagsFromScanner[i];
-            }
-
-            forever {
-                int flags = 0;
-                const char *szOutFilePath = scanner->next(opaq, &length, &flags);
-                if (szOutFilePath == 0)
-                    break;
-                QString includedFilePath = QString::fromLocal8Bit(szOutFilePath, length);
-                if (includedFilePath.isEmpty())
-                    continue;
-                bool isLocalInclude = (flags & SC_LOCAL_INCLUDE_FLAG);
-                scanResult.deps += ScanResultCache::Dependency(includedFilePath, isLocalInclude);
-            }
-
-            scanner->close(opaq);
-            m_scanResultCache->insert(artifact->filePath(), scanResult);
-        }
-
-        foreach (const FileTag &tag, scanResult.additionalFileTags) {
-            artifact->fileTags.insert(tag);
-            if (tag.name().startsWith("moc")) {
-                hasQObjectMacro = true;
-                if (m_logger.traceEnabled())
-                    m_logger.qbsTrace() << "[AUTOMOC] finds Q_OBJECT macro";
-            }
-        }
-
-        foreach (const ScanResultCache::Dependency &dependency, scanResult.deps) {
-            const QString &includedFilePath = dependency.filePath();
-            if (includedFilePath.startsWith(QLatin1String("moc_")) &&
-                includedFilePath.endsWith(QLatin1String(".cpp"))) {
-                if (m_logger.traceEnabled())
-                    m_logger.qbsTrace() << "[AUTOMOC] finds included file: " << includedFilePath;
-                includedMocCppFiles += includedFilePath;
-            }
-        }
-    }
-}
-
-static FileTags provideMocHeaderFileTags()
-{
-    FileTags fileTags;
-    fileTags << "moc_hpp" << "moc_hpp_inc" << "moc_plugin_hpp";
-    return fileTags;
-}
-
-bool AutoMoc::isVictimOfMoc(Artifact *artifact, FileType fileType, FileTag &foundMocFileTag)
-{
-    static const FileTags mocHeaderFileTags = provideMocHeaderFileTags();
-    static const FileTag mocCppFileTag = "moc_cpp";
-    foundMocFileTag.clear();
-    switch (fileType) {
-    case UnknownFileType:
-        break;
-    case HppFileType:
-        foreach (const FileTag &fileTag, artifact->fileTags) {
-            if (mocHeaderFileTags.contains(fileTag)) {
-                foundMocFileTag = fileTag;
-                break;
-            }
-        }
-        break;
-    case CppFileType:
-        if (artifact->fileTags.contains(mocCppFileTag))
-            foundMocFileTag = mocCppFileTag;
-        break;
-    }
-    return foundMocFileTag.isValid();
-}
-
-void AutoMoc::unmoc(Artifact *artifact, const FileTag &mocFileTag)
-{
-    if (m_logger.traceEnabled())
-        m_logger.qbsTrace() << "[AUTOMOC] unmoc'ing " << relativeArtifactFileName(artifact);
-
-    artifact->fileTags.remove(mocFileTag);
-
-    Artifact *generatedMocArtifact = 0;
-    foreach (Artifact *parent, artifact->parents) {
-        foreach (const FileTag &fileTag, parent->fileTags) {
-            if (fileTag == "hpp" || fileTag == "cpp") {
-                generatedMocArtifact = parent;
-                break;
-            }
-        }
-    }
-
-    if (!generatedMocArtifact) {
-        m_logger.qbsTrace() << "[AUTOMOC] generated moc artifact could not be found";
-        return;
-    }
-
-    TopLevelProject * const project = artifact->product->topLevelProject();
-    if (mocFileTag == "moc_hpp") {
-        Artifact *mocObjArtifact = 0;
-        foreach (Artifact *parent, generatedMocArtifact->parents) {
-            foreach (const FileTag &fileTag, parent->fileTags) {
-                if (fileTag == "obj" || fileTag == "fpicobj") {
-                    mocObjArtifact = parent;
-                    break;
-                }
-            }
-        }
-
-        if (!mocObjArtifact) {
-            m_logger.qbsTrace() << "[AUTOMOC] generated moc obj artifact could not be found";
-        } else {
-            if (m_logger.traceEnabled()) {
-                m_logger.qbsTrace() << "[AUTOMOC] removing moc obj artifact "
-                                    << relativeArtifactFileName(mocObjArtifact);
-            }
-            project->buildData->removeArtifact(mocObjArtifact, m_logger);
-            delete mocObjArtifact;
-        }
-    }
-
-    if (m_logger.traceEnabled()) {
-        m_logger.qbsTrace() << "[AUTOMOC] removing generated artifact "
-                            << relativeArtifactFileName(generatedMocArtifact);
-    }
-    project->buildData->removeArtifact(generatedMocArtifact, m_logger);
-    delete generatedMocArtifact;
-}
-
-const QList<ScannerPlugin *> &AutoMoc::cppScanners() const
-{
-    if (m_cppScanners.isEmpty())
-        m_cppScanners = ScannerPluginManager::scannersForFileTag("cpp");
-
-    return m_cppScanners;
-}
-
-const QList<ScannerPlugin *> &AutoMoc::hppScanners() const
-{
-    if (m_hppScanners.isEmpty())
-        m_hppScanners = ScannerPluginManager::scannersForFileTag("hpp");
-
-    return m_hppScanners;
-}
-
-} // namespace Internal
-} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/buildgraph.cpp b/src/lib/corelib/buildgraph/buildgraph.cpp
index 252f636cf..dd36ee15c 100644
--- a/src/lib/corelib/buildgraph/buildgraph.cpp
+++ b/src/lib/corelib/buildgraph/buildgraph.cpp
@@ -216,14 +216,14 @@ void setupScriptEngineForProduct(ScriptEngine *engine, const ResolvedProductCons
             rule->module->name.isEmpty() ? QScriptValue() : rule->module->name);
 }
 
-bool findPath(Artifact *u, Artifact *v, QList<Artifact*> &path)
+bool findPath(BuildGraphNode *u, BuildGraphNode *v, QList<BuildGraphNode *> &path)
 {
     if (u == v) {
         path.append(v);
         return true;
     }
 
-    for (ArtifactSet::const_iterator it = u->children.begin(); it != u->children.end(); ++it) {
+    for (NodeSet::const_iterator it = u->children.begin(); it != u->children.end(); ++it) {
         if (findPath(*it, v, path)) {
             path.prepend(u);
             return true;
@@ -242,28 +242,34 @@ bool findPath(Artifact *u, Artifact *v, QList<Artifact*> &path)
  * also:  children means i depend on or i am produced by
  *        parent means "produced by me" or "depends on me"
  */
-void connect(Artifact *p, Artifact *c)
+void connect(BuildGraphNode *p, BuildGraphNode *c)
 {
     QBS_CHECK(p != c);
-    foreach (const Artifact * const child, p->children)
-        if (child != c && child->filePath() == c->filePath())
-            throw ErrorInfo(QString::fromLocal8Bit("Artifact %1 already has a child artifact %2 as different object.").arg(p->filePath(), c->filePath()), CodeLocation(), true);
+    if (Artifact *ac = dynamic_cast<Artifact *>(c)) {
+        foreach (const Artifact * const child, ArtifactSet::fromNodeSet(p->children))
+            if (child != ac && child->filePath() == ac->filePath()) {
+                throw ErrorInfo(QString::fromLocal8Bit("%1 already has a child artifact %2 as "
+                                                       "different object.").arg(p->toString(),
+                                                                                ac->filePath()),
+                                CodeLocation(), true);
+            }
+    }
     p->children.insert(c);
     c->parents.insert(p);
     p->product->topLevelProject()->buildData->isDirty = true;
 }
 
-void loggedConnect(Artifact *u, Artifact *v, const Logger &logger)
+void loggedConnect(BuildGraphNode *u, BuildGraphNode *v, const Logger &logger)
 {
     QBS_CHECK(u != v);
     if (logger.traceEnabled()) {
         logger.qbsTrace() << QString::fromLocal8Bit("[BG] connect '%1' -> '%2'")
-                             .arg(relativeArtifactFileName(u), relativeArtifactFileName(v));
+                             .arg(u->toString(), v->toString());
     }
     connect(u, v);
 }
 
-static bool existsPath_impl(Artifact *u, Artifact *v, QSet<Artifact *> *seen)
+static bool existsPath_impl(BuildGraphNode *u, BuildGraphNode *v, QSet<BuildGraphNode *> *seen)
 {
     if (u == v)
         return true;
@@ -272,19 +278,27 @@ static bool existsPath_impl(Artifact *u, Artifact *v, QSet<Artifact *> *seen)
         return false;
 
     seen->insert(u);
-    for (ArtifactSet::const_iterator it = u->children.begin(); it != u->children.end(); ++it)
+    for (NodeSet::const_iterator it = u->children.begin(); it != u->children.end(); ++it)
         if (existsPath_impl(*it, v, seen))
             return true;
 
     return false;
 }
 
-static bool existsPath(Artifact *u, Artifact *v)
+static bool existsPath(BuildGraphNode *u, BuildGraphNode *v)
 {
-    QSet<Artifact *> seen;
+    QSet<BuildGraphNode *> seen;
     return existsPath_impl(u, v, &seen);
 }
 
+static QStringList toStringList(const QList<BuildGraphNode *> &path)
+{
+    QStringList lst;
+    foreach (BuildGraphNode *node, path)
+        lst << node->toString();
+    return lst;
+}
+
 bool safeConnect(Artifact *u, Artifact *v, const Logger &logger)
 {
     QBS_CHECK(u != v);
@@ -294,7 +308,7 @@ bool safeConnect(Artifact *u, Artifact *v, const Logger &logger)
     }
 
     if (existsPath(v, u)) {
-        QList<Artifact *> circle;
+        QList<BuildGraphNode *> circle;
         findPath(v, u, circle);
         logger.qbsTrace() << "[BG] safeConnect: circle detected " << toStringList(circle);
         return false;
@@ -304,31 +318,32 @@ bool safeConnect(Artifact *u, Artifact *v, const Logger &logger)
     return true;
 }
 
-void disconnect(Artifact *u, Artifact *v, const Logger &logger)
+void disconnect(BuildGraphNode *u, BuildGraphNode *v, const Logger &logger)
 {
     if (logger.traceEnabled()) {
         logger.qbsTrace() << QString::fromLocal8Bit("[BG] disconnect: '%1' '%2'")
-                             .arg(relativeArtifactFileName(u), relativeArtifactFileName(v));
+                             .arg(u->toString(), v->toString());
     }
     u->children.remove(v);
-    u->childrenAddedByScanner.remove(v);
     v->parents.remove(u);
+    u->onChildDisconnected(v);
 }
 
 void removeGeneratedArtifactFromDisk(Artifact *artifact, const Logger &logger)
 {
     if (artifact->artifactType != Artifact::Generated)
         return;
+    removeGeneratedArtifactFromDisk(artifact->filePath(), logger);
+}
 
-    QFile file(artifact->filePath());
+void removeGeneratedArtifactFromDisk(const QString &filePath, const Logger &logger)
+{
+    QFile file(filePath);
     if (!file.exists())
         return;
-
-    logger.qbsDebug() << "removing " << artifact->fileName();
-    if (!file.remove()) {
-        logger.qbsWarning() << QString::fromLocal8Bit("Cannot remove '%1'.")
-                               .arg(artifact->filePath());
-    }
+    logger.qbsDebug() << "removing " << filePath;
+    if (!file.remove())
+        logger.qbsWarning() << QString::fromLocal8Bit("Cannot remove '%1'.").arg(filePath);
 }
 
 QString relativeArtifactFileName(const Artifact *artifact)
@@ -404,7 +419,7 @@ void insertArtifact(const ResolvedProductPtr &product, Artifact *artifact, const
 {
     QBS_CHECK(!artifact->product);
     QBS_CHECK(!artifact->filePath().isEmpty());
-    QBS_CHECK(!product->buildData->artifacts.contains(artifact));
+    QBS_CHECK(!product->buildData->nodes.contains(artifact));
 #ifdef QT_DEBUG
     foreach (const ResolvedProductConstPtr &otherProduct, product->project->products) {
         if (lookupArtifact(otherProduct, artifact->filePath())) {
@@ -421,7 +436,7 @@ void insertArtifact(const ResolvedProductPtr &product, Artifact *artifact, const
         }
     }
 #endif
-    product->buildData->artifacts.insert(artifact);
+    product->buildData->nodes.insert(artifact);
     artifact->product = product;
     product->topLevelProject()->buildData->insertIntoLookupTable(artifact);
     product->topLevelProject()->buildData->isDirty = true;
@@ -443,25 +458,31 @@ static void doSanityChecksForProduct(const ResolvedProductConstPtr &product, con
     QBS_CHECK(!!product->enabled == !!buildData);
     if (!product->enabled)
         return;
-    foreach (Artifact * const ta, buildData->targetArtifacts) {
+    foreach (BuildGraphNode * const node, buildData->roots) {
         if (logger.traceEnabled())
-            logger.qbsTrace() << "Checking target artifact '" << ta->fileName() << "'.";
-        QBS_CHECK(buildData->artifacts.contains(ta));
+            logger.qbsTrace() << "Checking root node '" << node->toString() << "'.";
+        QBS_CHECK(buildData->nodes.contains(node));
     }
     QSet<QString> filePaths;
-    foreach (Artifact * const artifact, buildData->artifacts) {
-        logger.qbsDebug() << "Sanity checking artifact '" << artifact->fileName() << "'";
+    foreach (BuildGraphNode * const node, buildData->nodes) {
+        logger.qbsDebug() << "Sanity checking node '" << node->toString() << "'";
+        QBS_CHECK(node->product == product);
+        foreach (const BuildGraphNode * const parent, node->parents)
+            QBS_CHECK(parent->children.contains(node));
+        foreach (BuildGraphNode * const child, node->children) {
+            QBS_CHECK(child->parents.contains(node));
+            QBS_CHECK(child->product);
+            QBS_CHECK(!child->product->buildData.isNull());
+            QBS_CHECK(child->product->buildData->nodes.contains(child));
+        }
+
+        Artifact * const artifact = dynamic_cast<Artifact *>(node);
+        if (!artifact)
+            continue;
+
         QBS_CHECK(!filePaths.contains(artifact->filePath()));
         filePaths << artifact->filePath();
-        QBS_CHECK(artifact->product == product);
-        foreach (const Artifact * const parent, artifact->parents)
-            QBS_CHECK(parent->children.contains(artifact));
-        foreach (Artifact * const child, artifact->children) {
-            QBS_CHECK(child->parents.contains(artifact));
-            QBS_CHECK(!child->product.isNull());
-            QBS_CHECK(child->product->buildData);
-            QBS_CHECK(child->product->buildData->artifacts.contains(child));
-        }
+
         foreach (Artifact * const child, artifact->childrenAddedByScanner)
             QBS_CHECK(artifact->children.contains(child));
         const TransformerConstPtr transformer = artifact->transformer;
@@ -475,9 +496,9 @@ static void doSanityChecksForProduct(const ResolvedProductConstPtr &product, con
         ArtifactSet transformerOutputChildren;
         foreach (const Artifact * const output, transformer->outputs) {
             QBS_CHECK(output->transformer == transformer);
-            transformerOutputChildren.unite(output->children);
+            transformerOutputChildren.unite(ArtifactSet::fromNodeSet(output->children));
             QSet<QString> childFilePaths;
-            foreach (const Artifact * const a, output->children) {
+            foreach (const Artifact * const a, ArtifactSet::fromNodeSet(output->children)) {
                 if (childFilePaths.contains(a->filePath())) {
                     throw ErrorInfo(QString::fromLocal8Bit("There is more than one artifact for "
                         "file '%1' in the child list for output '%2'.")
diff --git a/src/lib/corelib/buildgraph/buildgraph.h b/src/lib/corelib/buildgraph/buildgraph.h
index 5244894cb..d0da37fa7 100644
--- a/src/lib/corelib/buildgraph/buildgraph.h
+++ b/src/lib/corelib/buildgraph/buildgraph.h
@@ -30,8 +30,6 @@
 #define QBS_BUILDGRAPH_H
 
 #include "forward_decls.h"
-#include "rulesapplicator.h"
-
 #include <language/forward_decls.h>
 
 #include <QScriptValue>
@@ -39,6 +37,7 @@
 
 namespace qbs {
 namespace Internal {
+class BuildGraphNode;
 class Logger;
 class ScriptEngine;
 class PrepareScriptObserver;
@@ -59,17 +58,16 @@ Artifact *lookupArtifact(const ResolvedProductConstPtr &product, const Artifact
 Artifact *createArtifact(const ResolvedProductPtr &product,
                          const SourceArtifactConstPtr &sourceArtifact, const Logger &logger);
 void insertArtifact(const ResolvedProductPtr &product, Artifact *artifact, const Logger &logger);
-void addTargetArtifacts(const ResolvedProductPtr &product,
-                        ArtifactsPerFileTagMap &artifactsPerFileTag, const Logger &logger);
 void dumpProductBuildData(const ResolvedProductConstPtr &product);
 
 
-bool findPath(Artifact *u, Artifact *v, QList<Artifact*> &path);
-void connect(Artifact *p, Artifact *c);
-void loggedConnect(Artifact *u, Artifact *v, const Logger &logger);
+bool findPath(BuildGraphNode *u, BuildGraphNode *v, QList<BuildGraphNode*> &path);
+void connect(BuildGraphNode *p, BuildGraphNode *c);
+void loggedConnect(BuildGraphNode *u, BuildGraphNode *v, const Logger &logger);
 bool safeConnect(Artifact *u, Artifact *v, const Logger &logger);
 void removeGeneratedArtifactFromDisk(Artifact *artifact, const Logger &logger);
-void disconnect(Artifact *u, Artifact *v, const Logger &logger);
+void removeGeneratedArtifactFromDisk(const QString &filePath, const Logger &logger);
+void disconnect(BuildGraphNode *u, BuildGraphNode *v, const Logger &logger);
 
 void setupScriptEngineForFile(ScriptEngine *engine, const ResolvedFileContextConstPtr &fileContext,
         QScriptValue targetObject);
@@ -80,15 +78,6 @@ QString relativeArtifactFileName(const Artifact *artifact); // Debugging helpers
 
 void doSanityChecks(const ResolvedProjectPtr &project, const Logger &logger);
 
-template <typename T>
-QStringList toStringList(const T &artifactContainer)
-{
-    QStringList l;
-    foreach (Artifact *n, artifactContainer)
-        l.append(relativeArtifactFileName(n));
-    return l;
-}
-
 } // namespace Internal
 } // namespace qbs
 
diff --git a/src/lib/corelib/buildgraph/buildgraph.pri b/src/lib/corelib/buildgraph/buildgraph.pri
index 4142d94bd..0674f2ca7 100644
--- a/src/lib/corelib/buildgraph/buildgraph.pri
+++ b/src/lib/corelib/buildgraph/buildgraph.pri
@@ -4,9 +4,9 @@ SOURCES += \
     $$PWD/artifactcleaner.cpp \
     $$PWD/artifactset.cpp \
     $$PWD/artifactvisitor.cpp \
-    $$PWD/automoc.cpp \
     $$PWD/buildgraph.cpp \
     $$PWD/buildgraphloader.cpp \
+    $$PWD/buildgraphnode.cpp \
     $$PWD/command.cpp \
     $$PWD/cycledetector.cpp \
     $$PWD/executor.cpp \
@@ -14,11 +14,15 @@ SOURCES += \
     $$PWD/filedependency.cpp \
     $$PWD/inputartifactscanner.cpp \
     $$PWD/jscommandexecutor.cpp \
+    $$PWD/nodeset.cpp \
     $$PWD/processcommandexecutor.cpp \
     $$PWD/productbuilddata.cpp \
     $$PWD/productinstaller.cpp \
     $$PWD/projectbuilddata.cpp \
+    $$PWD/qtmocscanner.cpp \
+    $$PWD/rescuableartifactdata.cpp \
     $$PWD/rulegraph.cpp \
+    $$PWD/rulenode.cpp \
     $$PWD/rulesapplicator.cpp \
     $$PWD/rulesevaluationcontext.cpp \
     $$PWD/scanresultcache.cpp \
@@ -31,9 +35,10 @@ HEADERS += \
     $$PWD/artifactcleaner.h \
     $$PWD/artifactset.h \
     $$PWD/artifactvisitor.h \
-    $$PWD/automoc.h \
     $$PWD/buildgraph.h \
     $$PWD/buildgraphloader.h \
+    $$PWD/buildgraphnode.h \
+    $$PWD/buildgraphvisitor.h \
     $$PWD/command.h \
     $$PWD/cycledetector.h \
     $$PWD/executor.h \
@@ -42,11 +47,15 @@ HEADERS += \
     $$PWD/forward_decls.h \
     $$PWD/inputartifactscanner.h \
     $$PWD/jscommandexecutor.h \
+    $$PWD/nodeset.h \
     $$PWD/processcommandexecutor.h \
     $$PWD/productbuilddata.h \
     $$PWD/productinstaller.h \
     $$PWD/projectbuilddata.h \
+    $$PWD/qtmocscanner.h \
+    $$PWD/rescuableartifactdata.h \
     $$PWD/rulegraph.h \
+    $$PWD/rulenode.h \
     $$PWD/rulesapplicator.h \
     $$PWD/rulesevaluationcontext.h \
     $$PWD/scanresultcache.h \
diff --git a/src/lib/corelib/buildgraph/buildgraphloader.cpp b/src/lib/corelib/buildgraph/buildgraphloader.cpp
index 1a7d0a7f1..21cdc9547 100644
--- a/src/lib/corelib/buildgraph/buildgraphloader.cpp
+++ b/src/lib/corelib/buildgraph/buildgraphloader.cpp
@@ -85,8 +85,10 @@ static void restoreBackPointers(const ResolvedProjectPtr &project)
         product->project = project;
         if (!product->buildData)
             continue;
-        foreach (Artifact * const a, product->buildData->artifacts)
-            project->topLevelProject()->buildData->insertIntoLookupTable(a);
+        foreach (BuildGraphNode * const n, product->buildData->nodes) {
+            if (Artifact *a = dynamic_cast<Artifact *>(n))
+                project->topLevelProject()->buildData->insertIntoLookupTable(a);
+        }
     }
 
     foreach (const ResolvedProjectPtr &subProject, project->subProjects) {
@@ -217,8 +219,11 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
 
             // If the product gets temporarily removed, its artifacts will get disconnected
             // and this structural information will no longer be directly available from them.
-            foreach (const Artifact * const a, product->buildData->artifacts)
-                childLists.insert(a, a->children);
+            foreach (const Artifact * const a,
+                     ArtifactSet::fromNodeSet(product->buildData->nodes)) {
+                childLists.insert(a, ChildrenInfo(ArtifactSet::fromNodeSet(a->children),
+                                                  a->childrenAddedByScanner));
+            }
         }
     }
 
@@ -248,7 +253,8 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
                 } else {
                     if (restoredProduct->enabled) {
                         QBS_CHECK(restoredProduct->buildData);
-                        foreach (Artifact * const a, newlyResolvedProduct->buildData->artifacts) {
+                        foreach (Artifact * const a,
+                                ArtifactSet::fromNodeSet(newlyResolvedProduct->buildData->nodes)) {
                             const bool removeFromDisk = a->artifactType == Artifact::Generated;
                             newlyResolvedProduct->topLevelProject()->buildData->removeArtifact(a,
                                     m_logger, removeFromDisk, true);
@@ -258,8 +264,8 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
                     productsWithChangedFiles.removeOne(restoredProduct);
                 }
                 if (newlyResolvedProduct->buildData) {
-                    foreach (Artifact * const a, newlyResolvedProduct->buildData->artifacts)
-                        a->product = newlyResolvedProduct;
+                    foreach (BuildGraphNode *node, newlyResolvedProduct->buildData->nodes)
+                        node->product = newlyResolvedProduct;
                 }
 
                 // Keep in list if build data still needs to be resolved.
@@ -495,7 +501,7 @@ bool BuildGraphLoader::checkTransformersForPropertyChanges(const ResolvedProduct
 {
     bool transformerChanges = false;
     QSet<TransformerConstPtr> seenTransformers;
-    foreach (Artifact * const artifact, restoredProduct->buildData->artifacts) {
+    foreach (Artifact *artifact, ArtifactSet::fromNodeSet(restoredProduct->buildData->nodes)) {
         const TransformerPtr transformer = artifact->transformer;
         if (!transformer || seenTransformers.contains(transformer))
             continue;
@@ -517,7 +523,7 @@ void BuildGraphLoader::onProductRemoved(const ResolvedProductPtr &product,
 
     product->project->products.removeOne(product);
     if (product->buildData) {
-        foreach (Artifact *artifact, product->buildData->artifacts)
+        foreach (Artifact *artifact, ArtifactSet::fromNodeSet(product->buildData->nodes))
             projectBuildData->removeArtifact(artifact, m_logger, removeArtifactsFromDisk, false);
     }
 }
@@ -529,7 +535,6 @@ void BuildGraphLoader::onProductFileListChanged(const ResolvedProductPtr &restor
 
     QBS_CHECK(newlyResolvedProduct->enabled);
 
-    ArtifactsPerFileTagMap artifactsPerFileTag;
     QList<Artifact *> addedArtifacts;
     ArtifactSet artifactsToRemove;
     QHash<QString, SourceArtifactConstPtr> oldArtifacts, newArtifacts;
@@ -601,20 +606,13 @@ void BuildGraphLoader::onProductFileListChanged(const ResolvedProductPtr &restor
             // handle added filetags
             foreach (const FileTag &addedFileTag, changedArtifact->fileTags - a->fileTags) {
                 artifact->fileTags += addedFileTag;
-                artifactsPerFileTag[addedFileTag] += artifact;
+                newlyResolvedProduct->registerAddedFileTag(addedFileTag, artifact);
             }
 
             // handle removed filetags
             foreach (const FileTag &removedFileTag, a->fileTags - changedArtifact->fileTags) {
                 artifact->fileTags -= removedFileTag;
-                foreach (Artifact *parent, artifact->parents) {
-                    if (parent->transformer && parent->transformer->rule->inputs.contains(removedFileTag)) {
-                        // this parent has been created because of the removed filetag
-                        newlyResolvedProduct->topLevelProject()->buildData
-                                ->removeArtifactAndExclusiveDependents(parent, m_logger, true,
-                                                                       &artifactsToRemove);
-                    }
-                }
+                newlyResolvedProduct->registerRemovedFileTag(removedFileTag, artifact);
             }
         }
 
@@ -631,23 +629,11 @@ void BuildGraphLoader::onProductFileListChanged(const ResolvedProductPtr &restor
         }
     }
 
-    // apply rules for new artifacts
-    foreach (Artifact *artifact, addedArtifacts)
-        foreach (const FileTag &ft, artifact->fileTags)
-            artifactsPerFileTag[ft] += artifact;
-    RulesApplicator(newlyResolvedProduct, artifactsPerFileTag, m_logger).applyAllRules();
-
-    addTargetArtifacts(newlyResolvedProduct, artifactsPerFileTag, m_logger);
-
-    // parents of removed artifacts must update their transformers
-    foreach (Artifact *removedArtifact, artifactsToRemove)
-        foreach (Artifact *parent, removedArtifact->parents)
-            newlyResolvedProduct->topLevelProject()->buildData->artifactsThatMustGetNewTransformers += parent;
-    newlyResolvedProduct->topLevelProject()->buildData->updateNodesThatMustGetNewTransformer(m_logger);
-
     // defer destruction of removed artifacts
     foreach (Artifact *artifact, artifactsToRemove)
         m_objectsToDelete << artifact;
+    foreach (Artifact * const artifact, addedArtifacts)
+        newlyResolvedProduct->registerAddedArtifact(artifact);
 }
 
 static SourceArtifactConstPtr findSourceArtifact(const ResolvedProductConstPtr &product,
@@ -673,7 +659,7 @@ bool BuildGraphLoader::checkForPropertyChanges(const TransformerPtr &restoredTra
         const QVariantMap properties = property.kind == Property::PropertyInProject
                 ? freshProduct->project->projectProperties() : freshProduct->properties->value();
         if (checkForPropertyChange(property, properties)) {
-            JavaScriptCommand * const pseudoCommand = new JavaScriptCommand;
+            const JavaScriptCommandPtr &pseudoCommand = JavaScriptCommand::create();
             pseudoCommand->setSourceCode(QLatin1String("random stuff that will cause "
                                                        "commandsEqual() to fail"));
             restoredTrafo->commands << pseudoCommand;
@@ -746,7 +732,7 @@ void BuildGraphLoader::replaceFileDependencyWithArtifact(const ResolvedProductPt
     foreach (const ResolvedProductPtr &product, fileDepProduct->topLevelProject()->allProducts()) {
         if (!product->buildData)
             continue;
-        foreach (Artifact *artifactInProduct, product->buildData->artifacts) {
+        foreach (Artifact *artifactInProduct, ArtifactSet::fromNodeSet(product->buildData->nodes)) {
             if (artifactInProduct->fileDependencies.contains(filedep)) {
                 artifactInProduct->fileDependencies.remove(filedep);
                 loggedConnect(artifactInProduct, artifact, m_logger);
@@ -758,24 +744,9 @@ void BuildGraphLoader::replaceFileDependencyWithArtifact(const ResolvedProductPt
     m_objectsToDelete << filedep;
 }
 
-static bool commandsEqual(const TransformerConstPtr &t1, const TransformerConstPtr &t2)
-{
-    if (t1->commands.count() != t2->commands.count())
-        return false;
-    for (int i = 0; i < t1->commands.count(); ++i)
-        if (!t1->commands.at(i)->equals(t2->commands.at(i)))
-            return false;
-    return true;
-}
-
-/**
- * Rescues the following data from the restoredProduct to newlyResolvedProduct:
- *    - dependencies between artifacts,
- *    - time stamps of artifacts, if their commands have not changed.
- */
 void BuildGraphLoader::rescueOldBuildData(const ResolvedProductConstPtr &restoredProduct,
-        const ResolvedProductPtr &newlyResolvedProduct,
-        const ProjectBuildData *oldBuildData, const ChildListHash &childLists)
+        const ResolvedProductPtr &newlyResolvedProduct, ProjectBuildData *oldBuildData,
+        const ChildListHash &childLists)
 {
     if (!restoredProduct->enabled || !newlyResolvedProduct->enabled)
         return;
@@ -785,22 +756,31 @@ void BuildGraphLoader::rescueOldBuildData(const ResolvedProductConstPtr &restore
                                                       "product '%1'").arg(restoredProduct->name);
     }
 
-    foreach (Artifact *artifact, newlyResolvedProduct->buildData->artifacts) {
+    // This is needed for artifacts created by manually added transformers, which are
+    // already present in the build graph.
+    // FIXME: This complete block could go away if Transformers were also to create their
+    // output artifacts at build time.
+    QList<Artifact *> oldArtifactsCreatedByTransformers;
+    foreach (Artifact *artifact,
+             ArtifactSet::fromNodeSet(newlyResolvedProduct->buildData->nodes)) {
+        if (!artifact->transformer)
+            continue;
         if (m_logger.traceEnabled()) {
             m_logger.qbsTrace() << QString::fromLocal8Bit("[BG]    artifact '%1'")
                                    .arg(artifact->fileName());
         }
 
         Artifact * const oldArtifact = lookupArtifact(restoredProduct, oldBuildData,
-                artifact->dirPath(), artifact->fileName(), true);
+                                                      artifact->dirPath(), artifact->fileName(),
+                                                      true);
         if (!oldArtifact || !oldArtifact->transformer) {
             if (m_logger.traceEnabled())
                 m_logger.qbsTrace() << QString::fromLocal8Bit("[BG]    no transformer data");
             continue;
         }
-
-        if (artifact->transformer
-                && !commandsEqual(artifact->transformer, oldArtifact->transformer)) {
+        oldArtifactsCreatedByTransformers << oldArtifact;
+        if (!commandListsAreEqual(artifact->transformer->commands,
+                                  oldArtifact->transformer->commands)) {
             if (m_logger.traceEnabled())
                 m_logger.qbsTrace() << QString::fromLocal8Bit("[BG]    artifact invalidated");
             removeGeneratedArtifactFromDisk(oldArtifact, m_logger);
@@ -808,30 +788,40 @@ void BuildGraphLoader::rescueOldBuildData(const ResolvedProductConstPtr &restore
         }
         artifact->setTimestamp(oldArtifact->timestamp());
 
-        foreach (Artifact * const oldChild, childLists.value(oldArtifact)) {
+        const ChildrenInfo &childrenInfo = childLists.value(oldArtifact);
+        foreach (Artifact * const oldChild, childrenInfo.children) {
             Artifact * const newChild = lookupArtifact(oldChild->product,
                     newlyResolvedProduct->topLevelProject()->buildData.data(),
                     oldChild->filePath(), true);
             if (!newChild || artifact->children.contains(newChild))
                     continue;
             safeConnect(artifact, newChild, m_logger);
+            if (childrenInfo.childrenAddedByScanner.contains(oldChild))
+                artifact->childrenAddedByScanner << newChild;
         }
     }
-}
 
-void addTargetArtifacts(const ResolvedProductPtr &product,
-                        ArtifactsPerFileTagMap &artifactsPerFileTag, const Logger &logger)
-{
-    foreach (const FileTag &fileTag, product->fileTags) {
-        foreach (Artifact * const artifact, artifactsPerFileTag.value(fileTag)) {
-            if (artifact->artifactType == Artifact::Generated)
-                product->buildData->targetArtifacts += artifact;
+    // This is needed for artifacts created by rules, which happens later in the executor.
+    foreach (Artifact * const oldArtifact,
+             ArtifactSet::fromNodeSet(restoredProduct->buildData->nodes)) {
+        if (!oldArtifact->transformer)
+            continue;
+        if (oldArtifactsCreatedByTransformers.contains(oldArtifact))
+            continue;
+        Artifact * const newArtifact = lookupArtifact(newlyResolvedProduct, oldArtifact, false);
+        if (!newArtifact) {
+            RescuableArtifactData rad;
+            rad.timeStamp = oldArtifact->timestamp();
+            rad.commands = oldArtifact->transformer->commands;
+            const ChildrenInfo &childrenInfo = childLists.value(oldArtifact);
+            foreach (Artifact * const child, childrenInfo.children) {
+                rad.children << RescuableArtifactData::ChildData(child->product->name,
+                        child->filePath(), childrenInfo.childrenAddedByScanner.contains(child));
+            }
+            newlyResolvedProduct->buildData->rescuableArtifactData.insert(
+                        oldArtifact->filePath(), rad);
         }
     }
-    if (product->buildData->targetArtifacts.isEmpty()) {
-        const QString msg = QString::fromLocal8Bit("No artifacts generated for product '%1'.");
-        logger.qbsDebug() << msg.arg(product->name);
-    }
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/buildgraphloader.h b/src/lib/corelib/buildgraph/buildgraphloader.h
index 0c0b7cb8b..a6b705d1f 100644
--- a/src/lib/corelib/buildgraph/buildgraphloader.h
+++ b/src/lib/corelib/buildgraph/buildgraphloader.h
@@ -45,6 +45,7 @@ namespace Internal {
 class FileDependency;
 class FileResourceBase;
 class FileTime;
+class NodeSet;
 class Property;
 
 class BuildGraphLoadResult
@@ -101,10 +102,17 @@ private:
     void replaceFileDependencyWithArtifact(const ResolvedProductPtr &fileDepProduct,
             FileDependency *filedep, Artifact *artifact);
 
-    typedef QHash<const Artifact *, ArtifactSet> ChildListHash;
+    struct ChildrenInfo {
+        ChildrenInfo() {}
+        ChildrenInfo(const ArtifactSet &c1, const ArtifactSet &c2)
+            : children(c1), childrenAddedByScanner(c2) {}
+        ArtifactSet children;
+        ArtifactSet childrenAddedByScanner;
+    };
+    typedef QHash<const Artifact *, ChildrenInfo> ChildListHash;
     void rescueOldBuildData(const ResolvedProductConstPtr &restoredProduct,
                             const ResolvedProductPtr &newlyResolvedProduct,
-                            const ProjectBuildData *oldBuildData,
+                            ProjectBuildData *oldBuildData,
                             const ChildListHash &childLists);
 
     RulesEvaluationContextPtr m_evalContext;
diff --git a/src/lib/corelib/buildgraph/buildgraphnode.cpp b/src/lib/corelib/buildgraph/buildgraphnode.cpp
new file mode 100644
index 000000000..d7eaac079
--- /dev/null
+++ b/src/lib/corelib/buildgraph/buildgraphnode.cpp
@@ -0,0 +1,80 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "buildgraphnode.h"
+
+#include "buildgraphvisitor.h"
+#include "projectbuilddata.h"
+#include <language/language.h>
+#include <logging/translator.h>
+#include <tools/error.h>
+#include <tools/qbsassert.h>
+
+//#include <qglobal.h>
+
+namespace qbs {
+namespace Internal {
+
+BuildGraphNode::BuildGraphNode()
+{
+}
+
+BuildGraphNode::~BuildGraphNode()
+{
+    foreach (BuildGraphNode *p, parents)
+        p->children.remove(this);
+    foreach (BuildGraphNode *c, children)
+        c->parents.remove(this);
+}
+
+void BuildGraphNode::onChildDisconnected(BuildGraphNode *child)
+{
+    Q_UNUSED(child);
+}
+
+void BuildGraphNode::acceptChildren(BuildGraphVisitor *visitor)
+{
+    foreach (BuildGraphNode *child, children)
+        child->accept(visitor);
+}
+
+void BuildGraphNode::load(PersistentPool &pool)
+{
+    children.load(pool);
+    // Parents must be updated after loading all nodes.
+}
+
+void BuildGraphNode::store(PersistentPool &pool) const
+{
+    children.store(pool);
+    // Do not store parents to avoid recursion.
+}
+
+} // namespace Internal
+} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/buildgraphnode.h b/src/lib/corelib/buildgraph/buildgraphnode.h
new file mode 100644
index 000000000..dbb046547
--- /dev/null
+++ b/src/lib/corelib/buildgraph/buildgraphnode.h
@@ -0,0 +1,85 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QBS_BUILDGRAPHNODE_H
+#define QBS_BUILDGRAPHNODE_H
+
+#include "nodeset.h"
+#include <language/forward_decls.h>
+#include <tools/persistentobject.h>
+#include <tools/weakpointer.h>
+
+namespace qbs {
+namespace Internal {
+
+class BuildGraphVisitor;
+class TopLevelProject;
+
+class BuildGraphNode : public virtual PersistentObject
+{
+    friend class NodeSet;
+public:
+    virtual ~BuildGraphNode();
+
+    NodeSet parents;
+    NodeSet children;
+    WeakPointer<ResolvedProduct> product;
+
+    enum BuildState
+    {
+        Untouched = 0,
+        Buildable,
+        Building,
+        Built
+    };
+
+    BuildState buildState;                  // Do not serialize. Will be refreshed for every build.
+
+    enum Type
+    {
+        ArtifactNodeType,
+        RuleNodeType
+    };
+
+    virtual Type type() const = 0;
+    virtual void accept(BuildGraphVisitor *visitor) = 0;
+    virtual QString toString() const = 0;
+    virtual void onChildDisconnected(BuildGraphNode *child);
+
+protected:
+    explicit BuildGraphNode();
+    void acceptChildren(BuildGraphVisitor *visitor);
+    void load(PersistentPool &pool);
+    void store(PersistentPool &pool) const;
+};
+
+} // namespace Internal
+} // namespace qbs
+
+#endif // QBS_BUILDGRAPHNODE_H
diff --git a/src/lib/corelib/buildgraph/buildgraphvisitor.h b/src/lib/corelib/buildgraph/buildgraphvisitor.h
new file mode 100644
index 000000000..0a574e910
--- /dev/null
+++ b/src/lib/corelib/buildgraph/buildgraphvisitor.h
@@ -0,0 +1,55 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QBS_BUILDGRAPHVISITOR_H
+#define QBS_BUILDGRAPHVISITOR_H
+
+namespace qbs {
+namespace Internal {
+
+class Artifact;
+class RuleNode;
+
+/*!
+ * \brief The BuildGraphVisitor class
+ *
+ * The return value of a visit method indicates whether the children of the current node
+ * are to be visited next.
+ */
+class BuildGraphVisitor
+{
+public:
+    virtual bool visit(Artifact *) { return true; }
+    virtual bool visit(RuleNode *) { return true; }
+};
+
+} // namespace Internal
+} // namespace qbs
+
+#endif // QBS_BUILDGRAPHVISITOR_H
diff --git a/src/lib/corelib/buildgraph/command.cpp b/src/lib/corelib/buildgraph/command.cpp
index 60ec93907..ea47191c5 100644
--- a/src/lib/corelib/buildgraph/command.cpp
+++ b/src/lib/corelib/buildgraph/command.cpp
@@ -50,16 +50,16 @@ AbstractCommand::~AbstractCommand()
 {
 }
 
-AbstractCommand *AbstractCommand::createByType(AbstractCommand::CommandType commandType)
+AbstractCommandPtr AbstractCommand::createByType(AbstractCommand::CommandType commandType)
 {
     switch (commandType) {
     case AbstractCommand::ProcessCommandType:
-        return new ProcessCommand;
+        return ProcessCommand::create();
     case AbstractCommand::JavaScriptCommandType:
-        return new JavaScriptCommand;
+        return JavaScriptCommand::create();
     }
     qFatal("%s: Invalid command type %d", Q_FUNC_INFO, commandType);
-    return 0;
+    return AbstractCommandPtr();
 }
 
 bool AbstractCommand::equals(const AbstractCommand *other) const
@@ -104,33 +104,33 @@ static QScriptValue js_Command(QScriptContext *context, QScriptEngine *engine)
     if (Q_UNLIKELY(!context->isCalledAsConstructor()))
         return context->throwError(Tr::tr("Command constructor called without new."));
 
-    static ProcessCommand commandPrototype;
+    static ProcessCommandPtr commandPrototype = ProcessCommand::create();
 
     QScriptValue program = context->argument(0);
     if (program.isUndefined())
-        program = engine->toScriptValue(commandPrototype.program());
+        program = engine->toScriptValue(commandPrototype->program());
     QScriptValue arguments = context->argument(1);
     if (arguments.isUndefined())
-        arguments = engine->toScriptValue(commandPrototype.arguments());
+        arguments = engine->toScriptValue(commandPrototype->arguments());
     QScriptValue cmd = js_CommandBase(context, engine);
     cmd.setProperty(QLatin1String("className"),
                     engine->toScriptValue(QString::fromLatin1("Command")));
     cmd.setProperty(QLatin1String("program"), program);
     cmd.setProperty(QLatin1String("arguments"), arguments);
     cmd.setProperty(QLatin1String("workingDir"),
-                    engine->toScriptValue(commandPrototype.workingDir()));
+                    engine->toScriptValue(commandPrototype->workingDir()));
     cmd.setProperty(QLatin1String("maxExitCode"),
-                    engine->toScriptValue(commandPrototype.maxExitCode()));
+                    engine->toScriptValue(commandPrototype->maxExitCode()));
     cmd.setProperty(QLatin1String("stdoutFilterFunction"),
-                    engine->toScriptValue(commandPrototype.stdoutFilterFunction()));
+                    engine->toScriptValue(commandPrototype->stdoutFilterFunction()));
     cmd.setProperty(QLatin1String("stderrFilterFunction"),
-                    engine->toScriptValue(commandPrototype.stderrFilterFunction()));
+                    engine->toScriptValue(commandPrototype->stderrFilterFunction()));
     cmd.setProperty(QLatin1String("responseFileThreshold"),
-                    engine->toScriptValue(commandPrototype.responseFileThreshold()));
+                    engine->toScriptValue(commandPrototype->responseFileThreshold()));
     cmd.setProperty(QLatin1String("responseFileUsagePrefix"),
-                    engine->toScriptValue(commandPrototype.responseFileUsagePrefix()));
+                    engine->toScriptValue(commandPrototype->responseFileUsagePrefix()));
     cmd.setProperty(QLatin1String("environment"),
-                    engine->toScriptValue(commandPrototype.environment().toStringList()));
+                    engine->toScriptValue(commandPrototype->environment().toStringList()));
     return cmd;
 }
 
@@ -236,12 +236,12 @@ static QScriptValue js_JavaScriptCommand(QScriptContext *context, QScriptEngine
                                   QLatin1String("JavaScriptCommand c'tor doesn't take arguments."));
     }
 
-    static JavaScriptCommand commandPrototype;
+    static JavaScriptCommandPtr commandPrototype = JavaScriptCommand::create();
     QScriptValue cmd = js_CommandBase(context, engine);
     cmd.setProperty(QLatin1String("className"),
                     engine->toScriptValue(QString::fromLatin1("JavaScriptCommand")));
     cmd.setProperty(QLatin1String("sourceCode"),
-                    engine->toScriptValue(commandPrototype.sourceCode()));
+                    engine->toScriptValue(commandPrototype->sourceCode()));
     return cmd;
 }
 
@@ -301,5 +301,41 @@ void JavaScriptCommand::store(QDataStream &s)
         << m_properties;
 }
 
+QList<AbstractCommandPtr> loadCommandList(QDataStream &s)
+{
+    QList<AbstractCommandPtr> commands;
+    int count;
+    s >> count;
+    commands.reserve(count);
+    while (--count >= 0) {
+        int cmdType;
+        s >> cmdType;
+        const AbstractCommandPtr cmd
+                = AbstractCommand::createByType(static_cast<AbstractCommand::CommandType>(cmdType));
+        cmd->load(s);
+        commands += cmd;
+    }
+    return commands;
+}
+
+void storeCommandList(const QList<AbstractCommandPtr> &commands, QDataStream &s)
+{
+    s << commands.count();
+    foreach (const AbstractCommandPtr &cmd, commands) {
+        s << int(cmd->type());
+        cmd->store(s);
+    }
+}
+
+bool commandListsAreEqual(const QList<AbstractCommandPtr> &l1, const QList<AbstractCommandPtr> &l2)
+{
+    if (l1.count() != l2.count())
+        return false;
+    for (int i = 0; i < l1.count(); ++i)
+        if (!l1.at(i)->equals(l2.at(i).data()))
+            return false;
+    return true;
+}
+
 } // namespace Internal
 } // namespace qbs
diff --git a/src/lib/corelib/buildgraph/command.h b/src/lib/corelib/buildgraph/command.h
index 69fa32299..0b9b10edb 100644
--- a/src/lib/corelib/buildgraph/command.h
+++ b/src/lib/corelib/buildgraph/command.h
@@ -30,6 +30,8 @@
 #ifndef QBS_COMMAND_H
 #define QBS_COMMAND_H
 
+#include "forward_decls.h"
+
 #include <tools/codelocation.h>
 
 #include <QProcessEnvironment>
@@ -50,7 +52,7 @@ public:
         JavaScriptCommandType
     };
 
-    static AbstractCommand *createByType(CommandType commandType);
+    static AbstractCommandPtr createByType(CommandType commandType);
     static QString defaultDescription() { return QString(); }
     static QString defaultHighLight() { return QString(); }
     static bool defaultIsSilent() { return false; }
@@ -79,10 +81,9 @@ private:
 class ProcessCommand : public AbstractCommand
 {
 public:
+    static ProcessCommandPtr create() { return ProcessCommandPtr(new ProcessCommand); }
     static void setupForJavaScript(QScriptValue targetObject);
 
-    ProcessCommand();
-
     CommandType type() const { return ProcessCommandType; }
     bool equals(const AbstractCommand *otherAbstractCommand) const;
     void fillFromScriptValue(const QScriptValue *scriptValue, const CodeLocation &codeLocation);
@@ -100,6 +101,8 @@ public:
     QProcessEnvironment environment() const { return m_environment; }
 
 private:
+    ProcessCommand();
+
     void getEnvironmentFromList(const QStringList &envList);
 
     QString m_program;
@@ -116,10 +119,9 @@ private:
 class JavaScriptCommand : public AbstractCommand
 {
 public:
+    static JavaScriptCommandPtr create() { return JavaScriptCommandPtr(new JavaScriptCommand); }
     static void setupForJavaScript(QScriptValue targetObject);
 
-    JavaScriptCommand();
-
     virtual CommandType type() const { return JavaScriptCommandType; }
     bool equals(const AbstractCommand *otherAbstractCommand) const;
     void fillFromScriptValue(const QScriptValue *scriptValue, const CodeLocation &codeLocation);
@@ -132,10 +134,17 @@ public:
     const QVariantMap &properties() const { return m_properties; }
 
 private:
+    JavaScriptCommand();
+
     QString m_sourceCode;
     QVariantMap m_properties;
 };
 
+QList<AbstractCommandPtr> loadCommandList(QDataStream &s);
+void storeCommandList(const QList<AbstractCommandPtr> &commands, QDataStream &s);
+
+bool commandListsAreEqual(const QList<AbstractCommandPtr> &l1, const QList<AbstractCommandPtr> &l2);
+
 } // namespace Internal
 } // namespace qbs
 
diff --git a/src/lib/corelib/buildgraph/cycledetector.cpp b/src/lib/corelib/buildgraph/cycledetector.cpp
index 1ab6b4bb8..767fd2b12 100644
--- a/src/lib/corelib/buildgraph/cycledetector.cpp
+++ b/src/lib/corelib/buildgraph/cycledetector.cpp
@@ -30,7 +30,8 @@
 
 #include "artifact.h"
 #include "buildgraph.h"
-#include "productbuilddata.h"
+#include "projectbuilddata.h"
+#include "rulenode.h"
 
 #include <language/language.h>
 #include <logging/translator.h>
@@ -40,51 +41,58 @@ namespace qbs {
 namespace Internal {
 
 CycleDetector::CycleDetector(const Logger &logger)
-    : ArtifactVisitor(0), m_parent(0), m_logger(logger)
+    : m_parent(0), m_logger(logger)
 {
 }
 
-void CycleDetector::visitProject(const ResolvedProjectConstPtr &project)
+void CycleDetector::visitProject(const TopLevelProjectConstPtr &project)
 {
     const QString description = QString::fromLocal8Bit("Cycle detection for project '%1'")
             .arg(project->name);
     TimedActivityLogger timeLogger(m_logger, description, QLatin1String("[BG] "), LoggerTrace);
-    ArtifactVisitor::visitProject(project);
+
+    project->accept(this);
 }
 
 void CycleDetector::visitProduct(const ResolvedProductConstPtr &product)
 {
-    if (!product->buildData)
-        return;
-    foreach (Artifact * const artifact, product->buildData->targetArtifacts)
-        visitArtifact(artifact);
+    product->accept(this);
+}
+
+bool CycleDetector::visit(Artifact *artifact)
+{
+    return visitNode(artifact);
 }
 
-void CycleDetector::visitArtifact(Artifact *artifact)
+bool CycleDetector::visit(RuleNode *ruleNode)
 {
-    if (Q_UNLIKELY(m_artifactsInCurrentPath.contains(artifact))) {
+    return visitNode(ruleNode);
+}
+
+bool CycleDetector::visitNode(BuildGraphNode *node)
+{
+    if (Q_UNLIKELY(m_nodesInCurrentPath.contains(node))) {
         ErrorInfo error(Tr::tr("Cycle in build graph detected."));
-        foreach (const Artifact * const a, cycle(artifact))
-            error.append(a->filePath());
+        foreach (const BuildGraphNode * const node, cycle(node))
+            error.append(node->toString());
         throw error;
     }
 
-    if (m_allArtifacts.contains(artifact))
-        return;
+    if (m_allNodes.contains(node))
+        return false;
 
-    m_artifactsInCurrentPath += artifact;
-    m_parent = artifact;
-    foreach (Artifact * const child, artifact->children)
-        visitArtifact(child);
-    m_artifactsInCurrentPath -= artifact;
-    m_allArtifacts += artifact;
+    m_nodesInCurrentPath += node;
+    m_parent = node;
+    foreach (BuildGraphNode * const child, node->children)
+        child->accept(this);
+    m_nodesInCurrentPath -= node;
+    m_allNodes += node;
+    return false;
 }
 
-void CycleDetector::doVisit(Artifact *) { }
-
-QList<Artifact *> CycleDetector::cycle(Artifact *doubleEntry)
+QList<BuildGraphNode *> CycleDetector::cycle(BuildGraphNode *doubleEntry)
 {
-    QList<Artifact *> path;
+    QList<BuildGraphNode *> path;
     findPath(doubleEntry, m_parent, path);
     return path << doubleEntry;
 }
diff --git a/src/lib/corelib/buildgraph/cycledetector.h b/src/lib/corelib/buildgraph/cycledetector.h
index 6e55efac3..690b3509e 100644
--- a/src/lib/corelib/buildgraph/cycledetector.h
+++ b/src/lib/corelib/buildgraph/cycledetector.h
@@ -29,7 +29,8 @@
 #ifndef QBS_CYCLEDETECTOR_H
 #define QBS_CYCLEDETECTOR_H
 
-#include "artifactvisitor.h"
+#include "buildgraphvisitor.h"
+#include <language/forward_decls.h>
 #include <logging/logger.h>
 
 #include <QSet>
@@ -37,23 +38,27 @@
 namespace qbs {
 namespace Internal {
 
-class CycleDetector : public ArtifactVisitor
+class BuildGraphNode;
+
+class CycleDetector : private BuildGraphVisitor
 {
 public:
     CycleDetector(const Logger &logger);
 
-    void visitProject(const ResolvedProjectConstPtr &project);
+    void visitProject(const TopLevelProjectConstPtr &project);
     void visitProduct(const ResolvedProductConstPtr &product);
-    void visitArtifact(Artifact *artifact);
 
 private:
-    void doVisit(Artifact *artifact);
+    bool visit(Artifact *artifact);
+    bool visit(RuleNode *ruleNode);
+
+    bool visitNode(BuildGraphNode *node);
 
-    QList<Artifact *> cycle(Artifact *doubleEntry);
+    QList<BuildGraphNode *> cycle(BuildGraphNode *doubleEntry);
 
-    QSet<Artifact *> m_allArtifacts;
-    QSet<Artifact *> m_artifactsInCurrentPath;
-    Artifact *m_parent;
+    QSet<BuildGraphNode *> m_allNodes;
+    QSet<BuildGraphNode *> m_nodesInCurrentPath;
+    BuildGraphNode *m_parent;
     Logger m_logger;
 };
 
diff --git a/src/lib/corelib/buildgraph/executor.cpp b/src/lib/corelib/buildgraph/executor.cpp
index 070b37d97..02e0d332a 100644
--- a/src/lib/corelib/buildgraph/executor.cpp
+++ b/src/lib/corelib/buildgraph/executor.cpp
@@ -28,14 +28,15 @@
 ****************************************************************************/
 #include "executor.h"
 
-#include "artifactvisitor.h"
-#include "automoc.h"
 #include "buildgraph.h"
+#include "command.h"
 #include "productbuilddata.h"
 #include "projectbuilddata.h"
 #include "cycledetector.h"
 #include "executorjob.h"
 #include "inputartifactscanner.h"
+#include "rescuableartifactdata.h"
+#include "rulenode.h"
 #include "rulesevaluationcontext.h"
 
 #include <buildgraph/transformer.h>
@@ -57,41 +58,7 @@
 namespace qbs {
 namespace Internal {
 
-class MocEffortCalculator : public ArtifactVisitor
-{
-public:
-    MocEffortCalculator() : ArtifactVisitor(Artifact::SourceFile), m_effort(0) {}
-
-    int effort() const { return m_effort; }
-
-private:
-    void doVisit(Artifact *) { m_effort += 10; }
-
-    int m_effort;
-};
-
-class BuildEffortCalculator : public ArtifactVisitor
-{
-public:
-    BuildEffortCalculator() : ArtifactVisitor(Artifact::Generated), m_effort(0) {}
-
-    int effort() const { return m_effort; }
-
-    static int multiplier(const Artifact *artifact) {
-        return artifact->transformer->rule->multiplex ? 200 : 20;
-    }
-
-private:
-    void doVisit(Artifact *artifact)
-    {
-        m_effort += multiplier(artifact);
-    }
-
-    int m_effort;
-};
-
-
-bool Executor::ComparePriority::operator() (const Artifact *x, const Artifact *y) const
+bool Executor::ComparePriority::operator() (const BuildGraphNode *x, const BuildGraphNode *y) const
 {
     return x->product->buildData->buildPriority < y->product->buildData->buildPriority;
 }
@@ -106,10 +73,6 @@ Executor::Executor(const Logger &logger, QObject *parent)
     , m_doDebug(logger.debugEnabled())
 {
     m_inputArtifactScanContext = new InputArtifactScannerContext(&m_scanResultCache);
-    m_autoMoc = new AutoMoc(logger);
-    connect(m_autoMoc, SIGNAL(reportCommandDescription(QString,QString)),
-            this, SIGNAL(reportCommandDescription(QString,QString)));
-    m_autoMoc->setScanResultCache(&m_scanResultCache);
 }
 
 Executor::~Executor()
@@ -119,7 +82,6 @@ Executor::~Executor()
         delete job;
     foreach (ExecutorJob *job, m_processingJobs.keys())
         delete job;
-    delete m_autoMoc; // delete before shared scan result cache
     delete m_inputArtifactScanContext;
 }
 
@@ -225,6 +187,7 @@ void Executor::doBuild()
     }
     QBS_CHECK(m_state == ExecutorIdle);
     m_leaves = Leaves();
+    m_changedSourceArtifacts.clear();
     m_error.clear();
     m_explicitlyCanceled = false;
     m_activeFileTags = FileTags::fromStringList(m_buildOptions.activeFileTags());
@@ -246,14 +209,11 @@ void Executor::doBuild()
 
     addExecutorJobs();
 
-    bool sourceFilesChanged = false;
-    prepareAllArtifacts(&sourceFilesChanged);
+    prepareAllNodes();
     prepareProducts();
     setupRootNodes();
-    prepareReachableArtifacts();
-    setupProgressObserver(sourceFilesChanged);
-    if (sourceFilesChanged)
-        runAutoMoc();
+    prepareReachableNodes();
+    setupProgressObserver();
     initLeaves();
     if (!scheduleJobs()) {
         m_logger.qbsTrace() << "Nothing to do at all, finishing.";
@@ -266,12 +226,12 @@ void Executor::setBuildOptions(const BuildOptions &buildOptions)
     m_buildOptions = buildOptions;
 }
 
-static void initArtifactsBottomUp(Artifact *artifact)
+static void initArtifactsBottomUp(BuildGraphNode *node)
 {
-    if (artifact->buildState == Artifact::Untouched)
+    if (node->buildState == BuildGraphNode::Untouched)
         return;
-    artifact->buildState = Artifact::Buildable;
-    foreach (Artifact *parent, artifact->parents)
+    node->buildState = BuildGraphNode::Buildable;
+    foreach (BuildGraphNode *parent, node->parents)
         initArtifactsBottomUp(parent);
 }
 
@@ -295,36 +255,37 @@ void Executor::initLeaves()
                            changedArtifacts.end());
 
     if (changedArtifacts.isEmpty()) {
-        QSet<Artifact *> seenArtifacts;
-        foreach (Artifact *root, m_roots)
-            initLeavesTopDown(root, seenArtifacts);
+        QSet<BuildGraphNode *> seenNodes;
+        foreach (BuildGraphNode *root, m_roots)
+            initLeavesTopDown(root, seenNodes);
     } else {
-        foreach (Artifact *artifact, changedArtifacts) {
+        foreach (BuildGraphNode *artifact, changedArtifacts) {
             m_leaves.push(artifact);
             initArtifactsBottomUp(artifact);
         }
     }
 }
 
-void Executor::initLeavesTopDown(Artifact *artifact, QSet<Artifact *> &seenArtifacts)
+void Executor::initLeavesTopDown(BuildGraphNode *node, QSet<BuildGraphNode *> &seenNodes)
 {
-    if (seenArtifacts.contains(artifact))
+    if (seenNodes.contains(node))
         return;
-    seenArtifacts += artifact;
+    seenNodes += node;
 
     // Artifacts that appear in the build graph after
     // prepareBuildGraph() has been called, must be initialized.
-    if (artifact->buildState == Artifact::Untouched) {
-        artifact->buildState = Artifact::Buildable;
-        if (artifact->artifactType == Artifact::SourceFile)
+    if (node->buildState == BuildGraphNode::Untouched) {
+        node->buildState = BuildGraphNode::Buildable;
+        Artifact *artifact = dynamic_cast<Artifact *>(node);
+        if (artifact && artifact->artifactType == Artifact::SourceFile)
             retrieveSourceFileTimestamp(artifact);
     }
 
-    if (artifact->children.isEmpty()) {
-        m_leaves.push(artifact);
+    if (node->children.isEmpty()) {
+        m_leaves.push(node);
     } else {
-        foreach (Artifact *child, artifact->children)
-            initLeavesTopDown(child, seenArtifacts);
+        foreach (BuildGraphNode *child, node->children)
+            initLeavesTopDown(child, seenNodes);
     }
 }
 
@@ -333,9 +294,30 @@ bool Executor::scheduleJobs()
 {
     QBS_CHECK(m_state == ExecutorRunning);
     while (!m_leaves.empty() && !m_availableJobs.isEmpty()) {
-        Artifact * const artifact = m_leaves.top();
+        BuildGraphNode * const nodeToBuild = m_leaves.top();
         m_leaves.pop();
-        buildArtifact(artifact);
+
+        switch (nodeToBuild->buildState) {
+        case BuildGraphNode::Untouched:
+            QBS_ASSERT(!"untouched node in leaves list", /* ignore */);
+            break;
+        case BuildGraphNode::Buildable:
+            // This is the only state in which we want to build a node.
+            nodeToBuild->accept(this);
+            break;
+        case BuildGraphNode::Building:
+            if (m_doDebug) {
+                m_logger.qbsDebug() << "[EXEC] " << nodeToBuild->toString();
+                m_logger.qbsDebug() << "[EXEC] node is currently being built. Skipping.";
+            }
+            break;
+        case BuildGraphNode::Built:
+            if (m_doDebug) {
+                m_logger.qbsDebug() << "[EXEC] " << nodeToBuild->toString();
+                m_logger.qbsDebug() << "[EXEC] node already built. Skipping.";
+            }
+            break;
+        }
     }
     return !m_leaves.empty() || !m_processingJobs.isEmpty();
 }
@@ -363,11 +345,12 @@ bool Executor::isUpToDate(Artifact *artifact) const
         return false;
     }
 
-    foreach (Artifact *child, artifact->children) {
-        QBS_CHECK(child->timestamp().isValid());
+    foreach (Artifact *childArtifact, ArtifactSet::fromNodeSet(artifact->children)) {
+        QBS_CHECK(childArtifact->timestamp().isValid());
         if (m_doDebug)
-            m_logger.qbsDebug() << "[UTD] child timestamp " << child->timestamp().toString();
-        if (artifact->timestamp() < child->timestamp())
+            m_logger.qbsDebug() << "[UTD] child timestamp "
+                                << childArtifact->timestamp().toString();
+        if (artifact->timestamp() < childArtifact->timestamp())
             return false;
     }
 
@@ -416,13 +399,6 @@ void Executor::buildArtifact(Artifact *artifact)
     if (m_doDebug)
         m_logger.qbsDebug() << "[EXEC] " << relativeArtifactFileName(artifact);
 
-    // Skip artifacts that are already built.
-    if (artifact->buildState == Artifact::Built) {
-        if (m_doDebug)
-            m_logger.qbsDebug() << "[EXEC] artifact already built. Skipping.";
-        return;
-    }
-
     // skip artifacts without transformer
     if (artifact->artifactType != Artifact::Generated) {
         // For source artifacts, that were not reachable when initializing the build, we must
@@ -441,6 +417,11 @@ void Executor::buildArtifact(Artifact *artifact)
     // Every generated artifact must have a transformer.
     QBS_CHECK(artifact->transformer);
 
+    bool childrenAddedDueToRescue;
+    rescueOldBuildData(artifact, &childrenAddedDueToRescue);
+    if (childrenAddedDueToRescue && checkForUnbuiltDependencies(artifact))
+        return;
+
     // Skip if outputs of this transformer are already built.
     // That means we already ran the transformation.
     foreach (Artifact *sideBySideArtifact, artifact->transformer->outputs) {
@@ -448,18 +429,18 @@ void Executor::buildArtifact(Artifact *artifact)
             continue;
         switch (sideBySideArtifact->buildState)
         {
-        case Artifact::Untouched:
-        case Artifact::Buildable:
+        case BuildGraphNode::Untouched:
+        case BuildGraphNode::Buildable:
             break;
-        case Artifact::Built:
+        case BuildGraphNode::Built:
             if (m_doDebug)
                 m_logger.qbsDebug() << "[EXEC] Side by side artifact already finished. Skipping.";
             finishArtifact(artifact);
             return;
-        case Artifact::Building:
+        case BuildGraphNode::Building:
             if (m_doDebug)
                 m_logger.qbsDebug() << "[EXEC] Side by side artifact processing. Skipping.";
-            artifact->buildState = Artifact::Building;
+            artifact->buildState = BuildGraphNode::Building;
             return;
         }
     }
@@ -496,36 +477,11 @@ void Executor::buildArtifact(Artifact *artifact)
     scanner.scan();
 
     // postpone the build of this artifact, if new dependencies found
-    if (scanner.newDependencyAdded()) {
-        bool buildingDependenciesFound = false;
-        QVector<Artifact *> unbuiltDependencies;
-        foreach (Artifact *dependency, artifact->children) {
-            switch (dependency->buildState) {
-            case Artifact::Untouched:
-            case Artifact::Buildable:
-                unbuiltDependencies += dependency;
-                break;
-            case Artifact::Building:
-                buildingDependenciesFound = true;
-                break;
-            case Artifact::Built:
-                // do nothing
-                break;
-            }
-        }
-        if (!unbuiltDependencies.isEmpty()) {
-            artifact->inputsScanned = false;
-            insertLeavesAfterAddingDependencies(unbuiltDependencies);
-            return;
-        }
-        if (buildingDependenciesFound) {
-            artifact->inputsScanned = false;
-            return;
-        }
-    }
+    if (scanner.newDependencyAdded() && checkForUnbuiltDependencies(artifact))
+        return;
 
     ExecutorJob *job = m_availableJobs.takeFirst();
-    artifact->buildState = Artifact::Building;
+    artifact->buildState = BuildGraphNode::Building;
     m_processingJobs.insert(job, artifact);
 
     Q_ASSERT_X(artifact->product, Q_FUNC_INFO,
@@ -535,6 +491,69 @@ void Executor::buildArtifact(Artifact *artifact)
     job->run(artifact->transformer.data(), artifact->product);
 }
 
+void Executor::executeRuleNode(RuleNode *ruleNode)
+{
+    ArtifactSet changedInputArtifacts;
+    if (ruleNode->rule()->isDynamic()) {
+        foreach (Artifact *artifact, m_changedSourceArtifacts) {
+            if (artifact->product != ruleNode->product)
+                continue;
+            if (ruleNode->rule()->acceptsAsInput(artifact))
+                changedInputArtifacts += artifact;
+        }
+        foreach (Artifact *artifact,
+                ArtifactSet::fromNodeSet(ruleNode->product->buildData->nodes)) {
+            if (artifact->artifactType == Artifact::SourceFile)
+                continue;
+            if (artifact->timestampRetrieved && !isUpToDate(artifact)
+                    && ruleNode->rule()->acceptsAsInput(artifact)) {
+                changedInputArtifacts += artifact;
+            }
+        }
+    }
+
+    RuleNode::ApplicationResult result;
+    ruleNode->apply(m_logger, changedInputArtifacts, &result);
+
+    if (result.upToDate) {
+        if (m_doDebug)
+            m_logger.qbsDebug() << "[EXEC] " << ruleNode->toString()
+                                << " is up to date. Skipping.";
+    } else {
+        if (m_doDebug)
+            m_logger.qbsDebug() << "[EXEC] " << ruleNode->toString();
+        const QVector<BuildGraphNode *> &createdNodes = result.createdNodes;
+        const WeakPointer<ResolvedProduct> &product = ruleNode->product;
+        QSet<RuleNode *> parentRules;
+        if (!createdNodes.isEmpty()) {
+            foreach (BuildGraphNode *parent, ruleNode->parents) {
+                if (RuleNode *parentRule = dynamic_cast<RuleNode *>(parent))
+                    parentRules += parentRule;
+            }
+        }
+        foreach (BuildGraphNode *node, createdNodes) {
+            if (m_doDebug)
+                m_logger.qbsDebug() << "[EXEC] rule created " << node->toString();
+            loggedConnect(node, ruleNode, m_logger);
+            Artifact *outputArtifact = dynamic_cast<Artifact *>(node);
+            if (!outputArtifact)
+                continue;
+            if (outputArtifact->fileTags.matches(product->fileTags))
+                product->buildData->roots += outputArtifact;
+
+            foreach (Artifact *inputArtifact, outputArtifact->transformer->inputs)
+                loggedConnect(ruleNode, inputArtifact, m_logger);
+
+            foreach (RuleNode *parentRule, parentRules)
+                loggedConnect(parentRule, outputArtifact, m_logger);
+        }
+        insertLeavesAfterAddingDependencies(createdNodes);
+    }
+    finishNode(ruleNode);
+    if (m_progressObserver)
+        m_progressObserver->incrementProgressValue();
+}
+
 void Executor::finishJob(ExecutorJob *job, bool success)
 {
     QBS_CHECK(job);
@@ -570,27 +589,21 @@ void Executor::finishJob(ExecutorJob *job, bool success)
     }
 }
 
-static bool allChildrenBuilt(Artifact *artifact)
+static bool allChildrenBuilt(BuildGraphNode *node)
 {
-    foreach (Artifact *child, artifact->children)
-        if (child->buildState != Artifact::Built)
+    foreach (BuildGraphNode *child, node->children)
+        if (child->buildState != BuildGraphNode::Built)
             return false;
     return true;
 }
 
-void Executor::finishArtifact(Artifact *leaf)
+void Executor::finishNode(BuildGraphNode *leaf)
 {
-    QBS_CHECK(leaf);
-
-    if (m_doTrace)
-        m_logger.qbsTrace() << "[EXEC] finishArtifact " << relativeArtifactFileName(leaf);
-
-    leaf->buildState = Artifact::Built;
-    m_scanResultCache.remove(leaf->filePath());
-    foreach (Artifact *parent, leaf->parents) {
-        if (parent->buildState != Artifact::Buildable) {
+    leaf->buildState = BuildGraphNode::Built;
+    foreach (BuildGraphNode *parent, leaf->parents) {
+        if (parent->buildState != BuildGraphNode::Buildable) {
             if (m_doTrace) {
-                m_logger.qbsTrace() << "[EXEC] parent " << relativeArtifactFileName(parent)
+                m_logger.qbsTrace() << "[EXEC] parent " << parent->toString()
                                     << " build state: " << toString(parent->buildState);
             }
             continue;
@@ -599,48 +612,58 @@ void Executor::finishArtifact(Artifact *leaf)
         if (allChildrenBuilt(parent)) {
             m_leaves.push(parent);
             if (m_doTrace) {
-                m_logger.qbsTrace() << "[EXEC] finishArtifact adds leaf "
-                        << relativeArtifactFileName(parent) << " " << toString(parent->buildState);
+                m_logger.qbsTrace() << "[EXEC] finishNode adds leaf "
+                        << parent->toString() << " " << toString(parent->buildState);
             }
         } else {
             if (m_doTrace) {
-                m_logger.qbsTrace() << "[EXEC] parent " << relativeArtifactFileName(parent)
+                m_logger.qbsTrace() << "[EXEC] parent " << parent->toString()
                                     << " build state: " << toString(parent->buildState);
             }
         }
     }
+}
+
+void Executor::finishArtifact(Artifact *leaf)
+{
+    QBS_CHECK(leaf);
+    if (m_doTrace)
+        m_logger.qbsTrace() << "[EXEC] finishArtifact " << relativeArtifactFileName(leaf);
 
-    if (leaf->transformer)
+    finishNode(leaf);
+    m_scanResultCache.remove(leaf->filePath());
+
+    if (leaf->transformer) {
         foreach (Artifact *sideBySideArtifact, leaf->transformer->outputs)
-            if (leaf != sideBySideArtifact && sideBySideArtifact->buildState == Artifact::Building)
+            if (leaf != sideBySideArtifact
+                    && sideBySideArtifact->buildState == BuildGraphNode::Building) {
                 finishArtifact(sideBySideArtifact);
-
-    if (m_progressObserver && leaf->artifactType == Artifact::Generated)
-        m_progressObserver->incrementProgressValue(BuildEffortCalculator::multiplier(leaf));
+            }
+    }
 }
 
-void Executor::insertLeavesAfterAddingDependencies_recurse(Artifact *const artifact,
-        QSet<Artifact *> *seenArtifacts, Leaves *leaves) const
+void Executor::insertLeavesAfterAddingDependencies_recurse(BuildGraphNode *const node,
+        QSet<BuildGraphNode *> *seenNodes, Leaves *leaves) const
 {
-    if (seenArtifacts->contains(artifact))
+    if (seenNodes->contains(node))
         return;
-    seenArtifacts->insert(artifact);
+    seenNodes->insert(node);
 
-    if (artifact->buildState == Artifact::Untouched)
-        artifact->buildState = Artifact::Buildable;
+    if (node->buildState == BuildGraphNode::Untouched)
+        node->buildState = BuildGraphNode::Buildable;
 
     bool isLeaf = true;
-    foreach (Artifact *child, artifact->children) {
-        if (child->buildState != Artifact::Built) {
+    foreach (BuildGraphNode *child, node->children) {
+        if (child->buildState != BuildGraphNode::Built) {
             isLeaf = false;
-            insertLeavesAfterAddingDependencies_recurse(child, seenArtifacts, leaves);
+            insertLeavesAfterAddingDependencies_recurse(child, seenNodes, leaves);
         }
     }
 
     if (isLeaf) {
         if (m_doDebug)
-            m_logger.qbsDebug() << "[EXEC] adding leaf " << relativeArtifactFileName(artifact);
-        leaves->push(artifact);
+            m_logger.qbsDebug() << "[EXEC] adding leaf " << node->toString();
+        leaves->push(node);
     }
 }
 
@@ -649,11 +672,11 @@ QString Executor::configString() const
     return tr(" for configuration %1").arg(m_project->id());
 }
 
-void Executor::insertLeavesAfterAddingDependencies(QVector<Artifact *> dependencies)
+void Executor::insertLeavesAfterAddingDependencies(QVector<BuildGraphNode *> dependencies)
 {
-    QSet<Artifact *> seenArtifacts;
-    foreach (Artifact *dependency, dependencies)
-        insertLeavesAfterAddingDependencies_recurse(dependency, &seenArtifacts, &m_leaves);
+    QSet<BuildGraphNode *> seenNodes;
+    foreach (BuildGraphNode *dependency, dependencies)
+        insertLeavesAfterAddingDependencies_recurse(dependency, &seenNodes, &m_leaves);
 }
 
 void Executor::cancelJobs()
@@ -665,20 +688,19 @@ void Executor::cancelJobs()
         job->cancel();
 }
 
-void Executor::setupProgressObserver(bool mocWillRun)
+void Executor::setupProgressObserver()
 {
     if (!m_progressObserver)
         return;
-    MocEffortCalculator mocEffortCalculator;
-    BuildEffortCalculator buildEffortCalculator;
-    foreach (const ResolvedProductConstPtr &product, m_productsToBuild)
-        buildEffortCalculator.visitProduct(product);
-    if (mocWillRun) {
-        foreach (const ResolvedProductConstPtr &product, m_productsToBuild)
-            mocEffortCalculator.visitProduct(product);
-    }
-    m_mocEffort = mocEffortCalculator.effort();
-    const int totalEffort = m_mocEffort + buildEffortCalculator.effort();
+    int totalEffort = 1; // For the effort after the last rule application;
+    foreach (const ResolvedProductConstPtr &product, m_productsToBuild) {
+        QBS_CHECK(product->buildData);
+        foreach (const BuildGraphNode * const node, product->buildData->nodes) {
+            const RuleNode * const ruleNode = dynamic_cast<const RuleNode *>(node);
+            if (ruleNode)
+                ++totalEffort;
+        }
+    }
     m_progressObserver->initialize(tr("Building%1").arg(configString()), totalEffort);
 }
 
@@ -721,27 +743,89 @@ void Executor::addExecutorJobs()
     }
 }
 
-void Executor::runAutoMoc()
+void Executor::rescueOldBuildData(Artifact *artifact, bool *childrenAdded = 0)
 {
-    bool autoMocApplied = false;
-    foreach (const ResolvedProductPtr &product, m_productsToBuild) {
-        if (m_progressObserver && m_progressObserver->canceled())
-            throw ErrorInfo(Tr::tr("Build canceled%1.").arg(configString()));
-        // HACK call the automoc thingy here only if we have use Qt/core module
-        foreach (const ResolvedModuleConstPtr &m, product->modules) {
-            if (m->name == QLatin1String("Qt/core")) {
-                autoMocApplied = true;
-                m_autoMoc->apply(product);
-                break;
+    if (childrenAdded)
+        *childrenAdded = false;
+    if (!artifact->oldDataPossiblyPresent)
+        return;
+    artifact->oldDataPossiblyPresent = false;
+    if (artifact->artifactType != Artifact::Generated)
+        return;
+
+    ResolvedProduct * const product = artifact->product.data();
+    AllRescuableArtifactData::Iterator it
+            = product->buildData->rescuableArtifactData.find(artifact->filePath());
+    if (it == product->buildData->rescuableArtifactData.end())
+        return;
+
+    const RescuableArtifactData &rad = it.value();
+    if (m_logger.traceEnabled()) {
+        m_logger.qbsTrace() << QString::fromLocal8Bit("[BG] Attempting to rescue data of "
+                                                      "artifact '%1'").arg(artifact->fileName());
+    }
+    if (commandListsAreEqual(artifact->transformer->commands, rad.commands)) {
+        artifact->setTimestamp(rad.timeStamp);
+        ResolvedProductPtr pseudoProduct = ResolvedProduct::create();
+        foreach (const RescuableArtifactData::ChildData &cd, rad.children) {
+            pseudoProduct->name = cd.productName;
+            Artifact * const child = lookupArtifact(pseudoProduct, m_project->buildData.data(),
+                                                    cd.childFilePath, true);
+            if (!child || artifact->children.contains(child))
+                continue;
+            if (childrenAdded)
+                *childrenAdded = true;
+            safeConnect(artifact, child, m_logger);
+            if (cd.addedByScanner)
+                artifact->childrenAddedByScanner << child;
+        }
+        if (m_logger.traceEnabled())
+            m_logger.qbsTrace() << "Data was rescued.";
+    } else {
+        removeGeneratedArtifactFromDisk(artifact->filePath(), m_logger);
+        if (m_logger.traceEnabled())
+            m_logger.qbsTrace() << "Transformer commands changed, data not rescued.";
+    }
+    product->buildData->rescuableArtifactData.erase(it);
+}
+
+bool Executor::checkForUnbuiltDependencies(Artifact *artifact)
+{
+    bool buildingDependenciesFound = false;
+    QVector<BuildGraphNode *> unbuiltDependencies;
+    foreach (BuildGraphNode *dependency, artifact->children) {
+        switch (dependency->buildState) {
+        case BuildGraphNode::Untouched:
+        case BuildGraphNode::Buildable:
+            if (m_logger.debugEnabled()) {
+                m_logger.qbsDebug() << "[EXEC] unbuilt dependency: "
+                                    << dependency->toString();
+            }
+            unbuiltDependencies += dependency;
+            break;
+        case BuildGraphNode::Building: {
+            if (m_logger.debugEnabled()) {
+                m_logger.qbsDebug() << "[EXEC] dependency in state 'Building': "
+                                    << dependency->toString();
             }
+            buildingDependenciesFound = true;
+            break;
+        }
+        case BuildGraphNode::Built:
+            // do nothing
+            break;
         }
     }
-    if (autoMocApplied) {
-        foreach (const ResolvedProductConstPtr &product, m_productsToBuild)
-            CycleDetector(m_logger).visitProduct(product);
+    if (!unbuiltDependencies.isEmpty()) {
+        artifact->inputsScanned = false;
+        insertLeavesAfterAddingDependencies(unbuiltDependencies);
+        return true;
     }
-    if (m_progressObserver)
-        m_progressObserver->incrementProgressValue(m_mocEffort);
+    if (buildingDependenciesFound) {
+        artifact->inputsScanned = false;
+        return true;
+    }
+    return false;
 }
 
 void Executor::onProcessError(const qbs::ErrorInfo &err)
@@ -790,12 +874,23 @@ void Executor::finish()
 
     QStringList unbuiltProductNames;
     foreach (const ResolvedProductPtr &product, m_productsToBuild) {
-        foreach (Artifact *artifact, product->buildData->targetArtifacts) {
-            if (artifact->buildState != Artifact::Built) {
+        foreach (BuildGraphNode *rootNode, product->buildData->roots) {
+            if (rootNode->buildState != BuildGraphNode::Built) {
                 unbuiltProductNames += product->name;
                 break;
             }
         }
+        if (!unbuiltProductNames.contains(product->name)) {
+            // Any element still left after a successful build has not been re-created
+            // by any rule and therefore does not exist anymore as an artifact.
+            foreach (const QString &filePath, product->buildData->rescuableArtifactData.keys())
+                removeGeneratedArtifactFromDisk(filePath, m_logger);
+            product->buildData->rescuableArtifactData.clear();
+
+            // Similar logic applies for the artifacts scheduled for potential rule application.
+            product->buildData->addedArtifactsByFileTag.clear();
+            product->buildData->removedArtifactsByFileTag.clear();
+        }
     }
 
     if (unbuiltProductNames.isEmpty()) {
@@ -813,58 +908,76 @@ void Executor::finish()
     emit finished();
 }
 
+bool Executor::visit(Artifact *artifact)
+{
+    buildArtifact(artifact);
+    return false;
+}
+
+bool Executor::visit(RuleNode *ruleNode)
+{
+    executeRuleNode(ruleNode);
+    return false;
+}
+
 /**
   * Sets the state of all artifacts in the graph to "untouched".
   * This must be done before doing a build.
   *
   * Retrieves the timestamps of source artifacts.
   *
-  * This function sets *sourceFilesChanged to true, if the timestamp of a reachable source artifact
-  * changed.
+  * This function also fills the list of changed source files.
   */
-void Executor::prepareAllArtifacts(bool *sourceFilesChanged)
+void Executor::prepareAllNodes()
 {
     foreach (const ResolvedProductPtr &product, m_productsToBuild) {
-        foreach (Artifact *artifact, product->buildData->artifacts) {
-            artifact->buildState = Artifact::Untouched;
-            artifact->inputsScanned = false;
-            artifact->timestampRetrieved = false;
-
-            if (artifact->artifactType == Artifact::SourceFile) {
-                const FileTime oldTimestamp = artifact->timestamp();
-                retrieveSourceFileTimestamp(artifact);
-                if (oldTimestamp != artifact->timestamp())
-                    *sourceFilesChanged = true;
-            }
-
-            // Timestamps of file dependencies must be invalid for every build.
-            foreach (FileDependency *fileDependency, artifact->fileDependencies)
-                fileDependency->clearTimestamp();
+        foreach (BuildGraphNode *node, product->buildData->nodes) {
+            node->buildState = BuildGraphNode::Untouched;
+            Artifact *artifact = dynamic_cast<Artifact *>(node);
+            if (artifact)
+                prepareArtifact(artifact);
         }
     }
 }
 
+void Executor::prepareArtifact(Artifact *artifact)
+{
+    artifact->inputsScanned = false;
+    artifact->timestampRetrieved = false;
+
+    if (artifact->artifactType == Artifact::SourceFile) {
+        const FileTime oldTimestamp = artifact->timestamp();
+        retrieveSourceFileTimestamp(artifact);
+        if (oldTimestamp != artifact->timestamp())
+            m_changedSourceArtifacts.append(artifact);
+    }
+
+    // Timestamps of file dependencies must be invalid for every build.
+    foreach (FileDependency *fileDependency, artifact->fileDependencies)
+        fileDependency->clearTimestamp();
+}
+
 /**
  * Walk the build graph top-down from the roots and for each reachable node N
  *  - mark N as buildable.
  */
-void Executor::prepareReachableArtifacts()
+void Executor::prepareReachableNodes()
 {
-    const Artifact::BuildState initialBuildState = m_buildOptions.changedFiles().isEmpty()
-            ? Artifact::Buildable : Artifact::Built;
-    foreach (Artifact *root, m_roots)
-        prepareReachableArtifacts_impl(root, initialBuildState);
+    const BuildGraphNode::BuildState initialBuildState = m_buildOptions.changedFiles().isEmpty()
+            ? BuildGraphNode::Buildable : BuildGraphNode::Built;
+    foreach (BuildGraphNode *root, m_roots)
+        prepareReachableNodes_impl(root, initialBuildState);
 }
 
-void Executor::prepareReachableArtifacts_impl(Artifact *artifact,
-        const Artifact::BuildState buildState)
+void Executor::prepareReachableNodes_impl(BuildGraphNode *node,
+        const BuildGraphNode::BuildState buildState)
 {
-    if (artifact->buildState != Artifact::Untouched)
+    if (node->buildState != BuildGraphNode::Untouched)
         return;
 
-    artifact->buildState = buildState;
-    foreach (Artifact *child, artifact->children)
-        prepareReachableArtifacts_impl(child, buildState);
+    node->buildState = buildState;
+    foreach (BuildGraphNode *child, node->children)
+        prepareReachableNodes_impl(child, buildState);
 }
 
 void Executor::prepareProducts()
@@ -879,28 +992,29 @@ void Executor::setupRootNodes()
 {
     m_roots.clear();
     foreach (const ResolvedProductPtr &product, m_productsToBuild) {
-        foreach (Artifact *targetArtifact, product->buildData->targetArtifacts)
-            m_roots += targetArtifact;
+        foreach (BuildGraphNode *root, product->buildData->roots)
+            m_roots += root;
     }
 }
 
 void Executor::updateBuildGraph(Artifact::BuildState buildState)
 {
-    QSet<Artifact *> seenArtifacts;
-    foreach (Artifact *root, m_roots)
+    QSet<BuildGraphNode *> seenArtifacts;
+    foreach (BuildGraphNode *root, m_roots)
         updateBuildGraph_impl(root, buildState, seenArtifacts);
 }
 
-void Executor::updateBuildGraph_impl(Artifact *artifact, Artifact::BuildState buildState, QSet<Artifact *> &seenArtifacts)
+void Executor::updateBuildGraph_impl(BuildGraphNode *node, Artifact::BuildState buildState,
+        QSet<BuildGraphNode *> &seenNodes)
 {
-    if (seenArtifacts.contains(artifact))
+    if (seenNodes.contains(node))
         return;
 
-    seenArtifacts += artifact;
-    artifact->buildState = buildState;
+    seenNodes += node;
+    node->buildState = buildState;
 
-    foreach (Artifact *child, artifact->children)
-        updateBuildGraph_impl(child, buildState, seenArtifacts);
+    foreach (BuildGraphNode *child, node->children)
+        updateBuildGraph_impl(child, buildState, seenNodes);
 }
 
 void Executor::setState(ExecutorState s)
diff --git a/src/lib/corelib/buildgraph/executor.h b/src/lib/corelib/buildgraph/executor.h
index 446ed8c81..e402e303b 100644
--- a/src/lib/corelib/buildgraph/executor.h
+++ b/src/lib/corelib/buildgraph/executor.h
@@ -31,6 +31,7 @@
 #define QBS_BUILDGRAPHEXECUTOR_H
 
 #include "forward_decls.h"
+#include "buildgraphvisitor.h"
 #include <buildgraph/artifact.h>
 #include <buildgraph/scanresultcache.h>
 #include <language/forward_decls.h>
@@ -46,13 +47,13 @@ namespace qbs {
 class ProcessResult;
 
 namespace Internal {
-class AutoMoc;
 class ExecutorJob;
 class FileTime;
 class InputArtifactScannerContext;
 class ProgressObserver;
+class RuleNode;
 
-class Executor : public QObject
+class Executor : public QObject, private BuildGraphVisitor
 {
     Q_OBJECT
 
@@ -82,44 +83,52 @@ private slots:
     void finish();
 
 private:
+    // BuildGraphVisitor implementation
+    bool visit(Artifact *artifact);
+    bool visit(RuleNode *ruleNode);
+
     enum ExecutorState { ExecutorIdle, ExecutorRunning, ExecutorCanceling };
 
     struct ComparePriority
     {
-        bool operator() (const Artifact *x, const Artifact *y) const;
+        bool operator() (const BuildGraphNode *x, const BuildGraphNode *y) const;
     };
 
-    typedef std::priority_queue<Artifact *, std::vector<Artifact *>, ComparePriority> Leaves;
+    typedef std::priority_queue<Artifact *, std::vector<BuildGraphNode *>, ComparePriority> Leaves;
 
     void doBuild();
-    void prepareAllArtifacts(bool *sourceFilesChanged);
-    void prepareReachableArtifacts();
-    void prepareReachableArtifacts_impl(Artifact *artifact, const Artifact::BuildState buildState);
+    void prepareAllNodes();
+    void prepareArtifact(Artifact *artifact);
+    void prepareReachableNodes();
+    void prepareReachableNodes_impl(BuildGraphNode *node, const Artifact::BuildState buildState);
     void prepareProducts();
     void setupRootNodes();
     void updateBuildGraph(Artifact::BuildState buildState);
-    void updateBuildGraph_impl(Artifact *artifact, Artifact::BuildState buildState, QSet<Artifact *> &seenArtifacts);
+    void updateBuildGraph_impl(BuildGraphNode *node, Artifact::BuildState buildState, QSet<BuildGraphNode *> &seenNodes);
     void initLeaves();
-    void initLeavesTopDown(Artifact *artifact, QSet<Artifact *> &seenArtifacts);
+    void initLeavesTopDown(BuildGraphNode *artifact, QSet<BuildGraphNode *> &seenArtifacts);
     bool scheduleJobs();
     void buildArtifact(Artifact *artifact);
+    void executeRuleNode(RuleNode *ruleNode);
     void finishJob(ExecutorJob *job, bool success);
+    void finishNode(BuildGraphNode *leaf);
     void finishArtifact(Artifact *artifact);
     void setState(ExecutorState);
     void addExecutorJobs();
-    void runAutoMoc();
-    void insertLeavesAfterAddingDependencies(QVector<Artifact *> dependencies);
+    void insertLeavesAfterAddingDependencies(QVector<BuildGraphNode *> dependencies);
     void cancelJobs();
-    void setupProgressObserver(bool mocWillRun);
+    void setupProgressObserver();
     void doSanityChecks();
     void handleError(const ErrorInfo &error);
+    void rescueOldBuildData(Artifact *artifact, bool *childrenAdded);
+    bool checkForUnbuiltDependencies(Artifact *artifact);
 
     bool mustExecuteTransformer(const TransformerPtr &transformer) const;
     bool isUpToDate(Artifact *artifact) const;
     void retrieveSourceFileTimestamp(Artifact *artifact) const;
     FileTime recursiveFileTime(const QString &filePath) const;
-    void insertLeavesAfterAddingDependencies_recurse(Artifact *const artifact,
-            QSet<Artifact *> *seenArtifacts, Leaves *leaves) const;
+    void insertLeavesAfterAddingDependencies_recurse(BuildGraphNode * const node,
+            QSet<BuildGraphNode *> *seenNodes, Leaves *leaves) const;
     QString configString() const;
 
     RulesEvaluationContextPtr m_evalContext;
@@ -131,12 +140,11 @@ private:
     ExecutorState m_state;
     TopLevelProjectPtr m_project;
     QList<ResolvedProductPtr> m_productsToBuild;
-    QList<Artifact *> m_roots;
+    QList<BuildGraphNode *> m_roots;
     Leaves m_leaves;
+    QList<Artifact *> m_changedSourceArtifacts;
     ScanResultCache m_scanResultCache;
     InputArtifactScannerContext *m_inputArtifactScanContext;
-    AutoMoc *m_autoMoc;
-    int m_mocEffort;
     ErrorInfo m_error;
     bool m_explicitlyCanceled;
     FileTags m_activeFileTags;
diff --git a/src/lib/corelib/buildgraph/executorjob.cpp b/src/lib/corelib/buildgraph/executorjob.cpp
index 3ad3df6d5..281d82e36 100644
--- a/src/lib/corelib/buildgraph/executorjob.cpp
+++ b/src/lib/corelib/buildgraph/executorjob.cpp
@@ -117,7 +117,7 @@ void ExecutorJob::runNextCommand()
         return;
     }
 
-    const AbstractCommand * const command = m_transformer->commands.at(m_currentCommandIdx);
+    const AbstractCommandPtr &command = m_transformer->commands.at(m_currentCommandIdx);
     switch (command->type()) {
     case AbstractCommand::ProcessCommandType:
         m_currentCommandExecutor = m_processCommandExecutor;
@@ -129,7 +129,7 @@ void ExecutorJob::runNextCommand()
         qFatal("Missing implementation for command type %d", command->type());
     }
 
-    m_currentCommandExecutor->start(m_transformer, command);
+    m_currentCommandExecutor->start(m_transformer, command.data());
 }
 
 void ExecutorJob::onCommandError(const ErrorInfo &err)
diff --git a/src/lib/corelib/buildgraph/forward_decls.h b/src/lib/corelib/buildgraph/forward_decls.h
index 7f3986a9b..2baa74d6d 100644
--- a/src/lib/corelib/buildgraph/forward_decls.h
+++ b/src/lib/corelib/buildgraph/forward_decls.h
@@ -45,6 +45,15 @@ typedef QSharedPointer<const Transformer> TransformerConstPtr;
 class RulesEvaluationContext;
 typedef QSharedPointer<RulesEvaluationContext> RulesEvaluationContextPtr;
 
+class AbstractCommand;
+typedef QSharedPointer<AbstractCommand> AbstractCommandPtr;
+
+class ProcessCommand;
+typedef QSharedPointer<ProcessCommand> ProcessCommandPtr;
+
+class JavaScriptCommand;
+typedef QSharedPointer<JavaScriptCommand> JavaScriptCommandPtr;
+
 } // namespace Internal
 } // namespace qbs
 
diff --git a/src/lib/corelib/buildgraph/inputartifactscanner.cpp b/src/lib/corelib/buildgraph/inputartifactscanner.cpp
index d1bae81dd..36defdcb0 100644
--- a/src/lib/corelib/buildgraph/inputartifactscanner.cpp
+++ b/src/lib/corelib/buildgraph/inputartifactscanner.cpp
@@ -301,7 +301,7 @@ resolved:
         // file or conflict with the writing process.
         if (filePathsToScan) {
             Artifact *artifactDependency = dynamic_cast<Artifact *>(resolvedDependency->file);
-            if (!artifactDependency || artifactDependency->buildState != Artifact::Building)
+            if (!artifactDependency || artifactDependency->buildState != BuildGraphNode::Building)
                 filePathsToScan->append(resolvedDependency->filePath);
         }
         handleDependency(*resolvedDependency);
@@ -360,7 +360,7 @@ void InputArtifactScanner::handleDependency(ResolvedDependency &dependency)
     } else {
         if (m_artifact->children.contains(artifactDependency))
             return;
-        if (insertIntoProduct && !product->buildData->artifacts.contains(artifactDependency))
+        if (insertIntoProduct && !product->buildData->nodes.contains(artifactDependency))
             insertArtifact(product, artifactDependency, m_logger);
         safeConnect(m_artifact, artifactDependency, m_logger);
         m_artifact->childrenAddedByScanner += artifactDependency;
diff --git a/src/lib/corelib/buildgraph/jscommandexecutor.cpp b/src/lib/corelib/buildgraph/jscommandexecutor.cpp
index b51dd6475..2c1973d90 100644
--- a/src/lib/corelib/buildgraph/jscommandexecutor.cpp
+++ b/src/lib/corelib/buildgraph/jscommandexecutor.cpp
@@ -84,7 +84,7 @@ public slots:
         setupScriptEngineForFile(scriptEngine, transformer->rule->prepareScript->fileContext, scope);
         setupScriptEngineForProduct(scriptEngine, transformer->product(), transformer->rule, scope,
                                     &observer);
-        transformer->setupInputs(scriptEngine, scope);
+        transformer->setupInputs(scope);
         transformer->setupOutputs(scriptEngine, scope);
 
         for (QVariantMap::const_iterator it = cmd->properties().constBegin();
diff --git a/src/lib/corelib/buildgraph/nodeset.cpp b/src/lib/corelib/buildgraph/nodeset.cpp
new file mode 100644
index 000000000..176cab53c
--- /dev/null
+++ b/src/lib/corelib/buildgraph/nodeset.cpp
@@ -0,0 +1,93 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "nodeset.h"
+
+#include "artifact.h"
+#include "rulenode.h"
+#include <language/language.h>  // because of RulePtr
+#include <tools/persistence.h>
+#include <tools/qbsassert.h>
+
+namespace qbs {
+namespace Internal {
+
+NodeSet::NodeSet()
+{
+}
+
+NodeSet::NodeSet(const NodeSet &other)
+    : m_data(other.m_data)
+{
+}
+
+NodeSet &NodeSet::unite(const NodeSet &other)
+{
+    m_data.insert(other.begin(), other.end());
+    return *this;
+}
+
+void NodeSet::remove(BuildGraphNode *node)
+{
+    m_data.erase(node);
+}
+
+void NodeSet::load(PersistentPool &pool)
+{
+    clear();
+    int i;
+    pool.stream() >> i;
+    for (; --i >= 0;) {
+        int t;
+        pool.stream() >> t;
+        BuildGraphNode *node = 0;
+        switch (static_cast<BuildGraphNode::Type>(t)) {
+        case BuildGraphNode::ArtifactNodeType:
+            node = pool.idLoad<Artifact>();
+            break;
+        case BuildGraphNode::RuleNodeType:
+            node = pool.idLoad<RuleNode>();
+            break;
+        }
+        QBS_CHECK(node);
+        insert(node);
+    }
+}
+
+void NodeSet::store(PersistentPool &pool) const
+{
+    pool.stream() << count();
+    for (NodeSet::const_iterator it = constBegin(); it != constEnd(); ++it) {
+        pool.stream() << int((*it)->type());
+        pool.store(*it);
+    }
+}
+
+} // namespace Internal
+} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/nodeset.h b/src/lib/corelib/buildgraph/nodeset.h
new file mode 100644
index 000000000..9bcf780ce
--- /dev/null
+++ b/src/lib/corelib/buildgraph/nodeset.h
@@ -0,0 +1,122 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QBS_NODESET_H
+#define QBS_NODESET_H
+
+#include <set>
+#include <cstddef>
+
+namespace qbs {
+namespace Internal {
+
+class BuildGraphNode;
+class PersistentPool;
+
+/**
+  * Set of build graph nodes.
+  * This is faster than QSet when iterating over the container.
+  */
+class NodeSet
+{
+public:
+    NodeSet();
+    NodeSet(const NodeSet &other);
+
+    NodeSet &unite(const NodeSet &other);
+
+    typedef std::set<BuildGraphNode *>::const_iterator const_iterator;
+    typedef std::set<BuildGraphNode *>::iterator iterator;
+    typedef BuildGraphNode * value_type;
+
+    iterator begin() { return m_data.begin(); }
+    iterator end() { return m_data.end(); }
+    const_iterator begin() const { return m_data.begin(); }
+    const_iterator end() const { return m_data.end(); }
+    const_iterator constBegin() const { return m_data.begin(); }
+    const_iterator constEnd() const { return m_data.end(); }
+
+    void insert(BuildGraphNode *node)
+    {
+        m_data.insert(node);
+    }
+
+    void operator+=(BuildGraphNode *node)
+    {
+        insert(node);
+    }
+
+    NodeSet &operator<<(BuildGraphNode *node)
+    {
+        insert(node);
+        return *this;
+    }
+
+    void remove(BuildGraphNode *node);
+
+    bool contains(BuildGraphNode *node) const
+    {
+        return m_data.find(node) != m_data.end();
+    }
+
+    void clear()
+    {
+        m_data.clear();
+    }
+
+    bool isEmpty() const
+    {
+        return m_data.empty();
+    }
+
+    int count() const
+    {
+        return (int)m_data.size();
+    }
+
+    void reserve(int)
+    {
+        // no-op
+    }
+
+    bool operator==(const NodeSet &other) const { return m_data == other.m_data; }
+    bool operator!=(const NodeSet &other) const { return !(*this == other); }
+
+    void load(PersistentPool &pool);
+    void store(PersistentPool &pool) const;
+
+
+private:
+    std::set<BuildGraphNode *> m_data;
+};
+
+} // namespace Internal
+} // namespace qbs
+
+#endif // QBS_NODESET_H
diff --git a/src/lib/corelib/buildgraph/productbuilddata.cpp b/src/lib/corelib/buildgraph/productbuilddata.cpp
index 0b9f36ab1..cdd3874e7 100644
--- a/src/lib/corelib/buildgraph/productbuilddata.cpp
+++ b/src/lib/corelib/buildgraph/productbuilddata.cpp
@@ -29,6 +29,7 @@
 #include "productbuilddata.h"
 
 #include "artifact.h"
+#include "command.h"
 #include "projectbuilddata.h"
 #include <language/language.h>
 #include <logging/logger.h>
@@ -41,19 +42,74 @@ namespace Internal {
 
 ProductBuildData::~ProductBuildData()
 {
-    qDeleteAll(artifacts);
+    qDeleteAll(nodes);
+}
+
+ArtifactSet ProductBuildData::targetArtifacts() const
+{
+    return ArtifactSet::fromNodeSet(roots);
+}
+
+static void loadArtifactSetByFileTag(PersistentPool &pool,
+                                     ProductBuildData::ArtifactSetByFileTag &s)
+{
+    int elemCount;
+    pool.stream() >> elemCount;
+    for (int i = 0; i < elemCount; ++i) {
+        QVariant fileTag;
+        pool.stream() >> fileTag;
+        ArtifactSet artifacts;
+        pool.loadContainer(artifacts);
+        s.insert(FileTag::fromSetting(fileTag), artifacts);
+    }
 }
 
 void ProductBuildData::load(PersistentPool &pool)
 {
-    pool.loadContainer(artifacts);
-    pool.loadContainer(targetArtifacts);
+    nodes.load(pool);
+    roots.load(pool);
+    int rescuableArtifactCount;
+    pool.stream() >> rescuableArtifactCount;
+    rescuableArtifactData.reserve(rescuableArtifactCount);
+    for (int i = 0; i < rescuableArtifactCount; ++i) {
+        const QString filePath = pool.idLoadString();
+        RescuableArtifactData elem;
+        elem.load(pool);
+        rescuableArtifactData.insert(filePath, elem);
+    }
+    loadArtifactSetByFileTag(pool, addedArtifactsByFileTag);
+    loadArtifactSetByFileTag(pool, removedArtifactsByFileTag);
+}
+
+static void storeArtifactSetByFileTag(PersistentPool &pool,
+                                      const ProductBuildData::ArtifactSetByFileTag &s)
+{
+    pool.stream() << s.count();
+    ProductBuildData::ArtifactSetByFileTag::ConstIterator it;
+    for (it = s.constBegin(); it != s.constEnd(); ++it) {
+        pool.stream() << it.key().toSetting();
+        pool.storeContainer(it.value());
+    }
 }
 
 void ProductBuildData::store(PersistentPool &pool) const
 {
-    pool.storeContainer(artifacts);
-    pool.storeContainer(targetArtifacts);
+    nodes.store(pool);
+    roots.store(pool);
+    pool.stream() << rescuableArtifactData.count();
+    for (AllRescuableArtifactData::ConstIterator it = rescuableArtifactData.constBegin();
+             it != rescuableArtifactData.constEnd(); ++it) {
+        pool.storeString(it.key());
+        it.value().store(pool);
+    }
+    storeArtifactSetByFileTag(pool, addedArtifactsByFileTag);
+    storeArtifactSetByFileTag(pool, removedArtifactsByFileTag);
+}
+
+void addArtifactToSet(Artifact *artifact, ProductBuildData::ArtifactSetByFileTag &container)
+{
+    foreach (const FileTag &tag, artifact->fileTags)
+        container[tag] += artifact;
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/productbuilddata.h b/src/lib/corelib/buildgraph/productbuilddata.h
index 1e4b4402e..10b4655be 100644
--- a/src/lib/corelib/buildgraph/productbuilddata.h
+++ b/src/lib/corelib/buildgraph/productbuilddata.h
@@ -30,8 +30,10 @@
 #define QBS_PRODUCTBUILDDATA_H
 
 #include "artifactset.h"
+#include "nodeset.h"
+#include "rescuableartifactdata.h"
+#include <language/filetags.h>
 #include <language/forward_decls.h>
-
 #include <tools/persistentobject.h>
 
 #include <QList>
@@ -39,6 +41,7 @@
 
 namespace qbs {
 namespace Internal {
+
 class Logger;
 
 class ProductBuildData : public PersistentObject
@@ -46,17 +49,33 @@ class ProductBuildData : public PersistentObject
 public:
     ~ProductBuildData();
 
-    QSet<Artifact *> targetArtifacts;
-    ArtifactSet artifacts;
-    QList<RuleConstPtr> topSortedRules;
+    ArtifactSet targetArtifacts() const;
+    NodeSet nodes;
+    NodeSet roots;
+
+    // After change tracking, this is the relevant data of artifacts that were in the build data
+    // of the restored product, and will potentially be re-created by our rules.
+    // If and when that happens, the relevant data will be copied over to the newly created
+    // artifact.
+    AllRescuableArtifactData rescuableArtifactData;
 
     // Do not store, initialized in executor. Higher prioritized artifacts are built first.
     unsigned int buildPriority;
 
+    typedef QHash<FileTag, ArtifactSet> ArtifactSetByFileTag;
+    ArtifactSetByFileTag addedArtifactsByFileTag;
+    ArtifactSetByFileTag removedArtifactsByFileTag;
+
+    // TODO: Serialize.
+    typedef QHash<RuleConstPtr, ArtifactSet> ArtifactSetByRule;
+    ArtifactSetByRule artifactsWithChangedInputsPerRule;
+
     void load(PersistentPool &pool);
     void store(PersistentPool &pool) const;
 };
 
+void addArtifactToSet(Artifact *artifact, ProductBuildData::ArtifactSetByFileTag &container);
+
 } // namespace Internal
 } // namespace qbs
 
diff --git a/src/lib/corelib/buildgraph/productinstaller.cpp b/src/lib/corelib/buildgraph/productinstaller.cpp
index 867ad1370..c7df23d24 100644
--- a/src/lib/corelib/buildgraph/productinstaller.cpp
+++ b/src/lib/corelib/buildgraph/productinstaller.cpp
@@ -82,7 +82,7 @@ void ProductInstaller::install()
     QList<const Artifact *> artifactsToInstall;
     foreach (const ResolvedProductConstPtr &product, m_products) {
         QBS_CHECK(product->buildData);
-        foreach (const Artifact *artifact, product->buildData->artifacts) {
+        foreach (const Artifact *artifact, ArtifactSet::fromNodeSet(product->buildData->nodes)) {
             if (artifact->properties->qbsPropertyValue(QLatin1String("install")).toBool())
                 artifactsToInstall += artifact;
         }
diff --git a/src/lib/corelib/buildgraph/projectbuilddata.cpp b/src/lib/corelib/buildgraph/projectbuilddata.cpp
index 8e3bfd3e0..96d0e925c 100644
--- a/src/lib/corelib/buildgraph/projectbuilddata.cpp
+++ b/src/lib/corelib/buildgraph/projectbuilddata.cpp
@@ -30,8 +30,11 @@
 
 #include "artifact.h"
 #include "buildgraph.h"
+#include "buildgraphvisitor.h"
 #include "productbuilddata.h"
 #include "command.h"
+#include "rulegraph.h"
+#include "rulenode.h"
 #include "rulesapplicator.h"
 #include "rulesevaluationcontext.h"
 #include "transformer.h"
@@ -111,36 +114,36 @@ static void disconnectArtifactChildren(Artifact *artifact, const Logger &logger)
         logger.qbsTrace() << QString::fromLocal8Bit("[BG] disconnectChildren: '%1'")
                              .arg(relativeArtifactFileName(artifact));
     }
-    foreach (Artifact * const child, artifact->children)
+    foreach (BuildGraphNode * const child, artifact->children)
         child->parents.remove(artifact);
     artifact->children.clear();
     artifact->childrenAddedByScanner.clear();
 }
 
-static void disconnectArtifactParents(Artifact *artifact, ProjectBuildData *projectBuildData,
-                               const Logger &logger)
+static void disconnectArtifactParents(Artifact *artifact, const Logger &logger)
 {
     if (logger.traceEnabled()) {
         logger.qbsTrace() << QString::fromLocal8Bit("[BG] disconnectParents: '%1'")
                              .arg(relativeArtifactFileName(artifact));
     }
-    foreach (Artifact * const parent, artifact->parents) {
+    foreach (BuildGraphNode * const parent, artifact->parents) {
         parent->children.remove(artifact);
-        parent->childrenAddedByScanner.remove(artifact);
-        if (parent->transformer) {
-            parent->transformer->inputs.remove(artifact);
-            projectBuildData->artifactsThatMustGetNewTransformers += parent;
+        Artifact *parentArtifact = dynamic_cast<Artifact *>(parent);
+        if (parentArtifact) {
+            QBS_CHECK(parentArtifact->transformer);
+            parentArtifact->childrenAddedByScanner.remove(artifact);
+            parentArtifact->transformer->inputs.remove(artifact);
+            parentArtifact->product->registerArtifactWithChangedInputs(parentArtifact);
         }
     }
 
     artifact->parents.clear();
 }
 
-static void disconnectArtifact(Artifact *artifact, ProjectBuildData *projectBuildData,
-                               const Logger &logger)
+static void disconnectArtifact(Artifact *artifact, const Logger &logger)
 {
     disconnectArtifactChildren(artifact, logger);
-    disconnectArtifactParents(artifact, projectBuildData, logger);
+    disconnectArtifactParents(artifact, logger);
 }
 
 /*!
@@ -154,13 +157,14 @@ void ProjectBuildData::removeArtifactAndExclusiveDependents(Artifact *artifact,
 {
     if (removedArtifacts)
         removedArtifacts->insert(artifact);
-    foreach (Artifact *parent, artifact->parents) {
+
+    foreach (Artifact *parent, ArtifactSet::fromNodeSet(artifact->parents)) {
         bool removeParent = false;
         disconnect(parent, artifact, logger);
         if (parent->children.isEmpty()) {
             removeParent = true;
         } else if (parent->transformer) {
-            artifactsThatMustGetNewTransformers += parent;
+            parent->product->registerArtifactWithChangedInputs(parent);
             parent->transformer->inputs.remove(artifact);
             removeParent = parent->transformer->inputs.isEmpty();
         }
@@ -171,6 +175,7 @@ void ProjectBuildData::removeArtifactAndExclusiveDependents(Artifact *artifact,
     }
     const bool removeFromDisk = artifact->artifactType == Artifact::Generated;
     removeArtifact(artifact, logger, removeFromDisk, removeFromProduct);
+
 }
 
 void ProjectBuildData::removeArtifact(Artifact *artifact,
@@ -183,49 +188,18 @@ void ProjectBuildData::removeArtifact(Artifact *artifact,
         removeGeneratedArtifactFromDisk(artifact, logger);
     removeFromLookupTable(artifact);
     if (removeFromProduct) {
-        artifact->product->buildData->artifacts.remove(artifact);
-        artifact->product->buildData->targetArtifacts.remove(artifact);
+        artifact->product->buildData->nodes.remove(artifact);
+        artifact->product->buildData->roots.remove(artifact);
     }
-    disconnectArtifact(artifact, this, logger);
-    artifactsThatMustGetNewTransformers -= artifact;
-    isDirty = true;
-}
 
-void ProjectBuildData::updateNodesThatMustGetNewTransformer(const Logger &logger)
-{
-    RulesEvaluationContext::Scope s(evaluationContext.data());
-    foreach (Artifact *artifact, artifactsThatMustGetNewTransformers)
-        updateNodeThatMustGetNewTransformer(artifact, logger);
-    artifactsThatMustGetNewTransformers.clear();
-}
-
-void ProjectBuildData::updateNodeThatMustGetNewTransformer(Artifact *artifact, const Logger &logger)
-{
-    QBS_CHECK(artifact->transformer);
+    // If removal is requested and the executor has not run since the time the artifact was last
+    // added, we must undo the "register" operation.
+    artifact->product->unregisterAddedArtifact(artifact);
 
-    if (logger.debugEnabled()) {
-        logger.qbsDebug() << "[BG] updating transformer for "
-                            << relativeArtifactFileName(artifact);
-    }
-
-    removeGeneratedArtifactFromDisk(artifact, logger);
-    artifact->autoMocTimestamp.clear();
-    artifact->clearTimestamp();
-
-    const RuleConstPtr rule = artifact->transformer->rule;
+    disconnectArtifact(artifact, logger);
+    if (artifact->transformer)
+        artifact->product->unregisterArtifactWithChangedInputs(artifact);
     isDirty = true;
-
-    QBS_CHECK(artifact->transformer);
-    foreach (Artifact * const sibling, artifact->transformer->outputs)
-        sibling->transformer.clear();
-
-    ArtifactsPerFileTagMap artifactsPerFileTag;
-    foreach (Artifact *input, artifact->children) {
-        foreach (const FileTag &fileTag, input->fileTags)
-            artifactsPerFileTag[fileTag] += input;
-    }
-    RulesApplicator rulesApplier(artifact->product, artifactsPerFileTag, logger);
-    rulesApplier.applyRule(rule);
 }
 
 void ProjectBuildData::load(PersistentPool &pool)
@@ -275,10 +249,172 @@ void BuildDataResolver::resolveProductBuildDataForExistingProject(const TopLevel
     m_project = project;
     foreach (const ResolvedProductPtr &product, freshProducts) {
         if (product->enabled)
-            resolveProductBuildData(product);
+            resolveProductBuildDataForExistingProject(product);
+    }
+}
+
+static QSet<ResolvedProductPtr> findDependentProducts(const ResolvedProductPtr &product)
+{
+    QSet<ResolvedProductPtr> result;
+    foreach (const ResolvedProductPtr &parent, product->topLevelProject()->allProducts()) {
+        if (parent->dependencies.contains(product))
+            result += parent;
+    }
+    return result;
+}
+
+class FindLeafRules : public BuildGraphVisitor
+{
+public:
+    FindLeafRules()
+    {
+    }
+
+    const QSet<RuleNode *> &apply(const ResolvedProductPtr &product)
+    {
+        m_result.clear();
+        m_product = product;
+        foreach (BuildGraphNode *n, product->buildData->nodes)
+            n->accept(this);
+        return m_result;
+    }
+
+private:
+    virtual bool visit(Artifact *)
+    {
+        return false;
+    }
+
+    virtual bool visit(RuleNode *node)
+    {
+        if (!hasChildRuleInThisProduct(node))
+            m_result << node;
+        return false;
+    }
+
+    bool hasChildRuleInThisProduct(const RuleNode *node) const
+    {
+        foreach (BuildGraphNode *c, node->children) {
+            if (c->product == m_product && c->type() == BuildGraphNode::RuleNodeType)
+                return true;
+        }
+        return false;
+    }
+
+    ResolvedProductPtr m_product;
+    QSet<RuleNode *> m_result;
+};
+
+class FindRootRules : public BuildGraphVisitor
+{
+public:
+    FindRootRules()
+    {
+    }
+
+    const QList<RuleNode *> &apply(const ResolvedProductPtr &product)
+    {
+        m_result.clear();
+        foreach (BuildGraphNode *n, product->buildData->roots)
+            n->accept(this);
+        return m_result;
+    }
+
+private:
+    virtual bool visit(Artifact *)
+    {
+        return true;
+    }
+
+    virtual bool visit(RuleNode *node)
+    {
+        m_result << node;
+        return true;
+    }
+
+    QList<RuleNode *> m_result;
+};
+
+
+void BuildDataResolver::resolveProductBuildDataForExistingProject(const ResolvedProductPtr &product)
+{
+    resolveProductBuildData(product);
+
+    // Connect the leaf rules of all dependent products to the root rules of this product.
+    const QList<RuleNode *> rootRules = FindRootRules().apply(product);
+    QSet<ResolvedProductPtr> dependents = findDependentProducts(product);
+    foreach (const ResolvedProductPtr &dependentProduct, dependents) {
+        foreach (RuleNode *leaf, FindLeafRules().apply(dependentProduct)) {
+            foreach (RuleNode *root, rootRules) {
+                loggedConnect(leaf, root, m_logger);
+            }
+        }
     }
 }
 
+class CreateRuleNodes : public RuleGraphVisitor
+{
+public:
+    CreateRuleNodes(const ResolvedProductPtr &product, const Logger &logger)
+        : m_product(product), m_logger(logger)
+    {
+    }
+
+    const QSet<RuleNode *> &leaves() const
+    {
+        return m_leaves;
+    }
+
+private:
+    const ResolvedProductPtr &m_product;
+    const Logger &m_logger;
+    QHash<RuleConstPtr, RuleNode *> m_nodePerRule;
+    QSet<const Rule *> m_rulesOnPath;
+    QList<const Rule *> m_rulePath;
+    QSet<RuleNode *> m_leaves;
+
+    void visit(const RuleConstPtr &parentRule, const RuleConstPtr &rule)
+    {
+        if (m_rulesOnPath.contains(rule.data())) {
+            QString pathstr;
+            foreach (const Rule *r, m_rulePath) {
+                pathstr += QLatin1Char('\n') + r->toString() + QLatin1Char('\t')
+                        + r->prepareScript->location.toString();
+            }
+            throw ErrorInfo(Tr::tr("Cycle detected in rule dependencies: %1").arg(pathstr));
+        }
+        m_rulesOnPath.insert(rule.data());
+        m_rulePath.append(rule.data());
+        RuleNode *node = m_nodePerRule.value(rule);
+        if (!node) {
+            node = new RuleNode;
+            m_leaves.insert(node);
+            m_nodePerRule.insert(rule, node);
+            node->product = m_product;
+            node->setRule(rule);
+            m_product->buildData->nodes += node;
+            if (m_logger.debugEnabled()) {
+                m_logger.qbsDebug() << "[BG] create " << node->toString()
+                                    << " for product " << m_product->name;
+            }
+        }
+        if (parentRule) {
+            RuleNode *parent = m_nodePerRule.value(parentRule);
+            QBS_CHECK(parent);
+            loggedConnect(parent, node, m_logger);
+            m_leaves.remove(parent);
+        } else {
+            m_product->buildData->roots += node;
+        }
+    }
+
+    void endVisit(const RuleConstPtr &rule)
+    {
+        m_rulesOnPath.remove(rule.data());
+        m_rulePath.removeLast();
+    }
+};
+
 void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &product)
 {
     if (product->buildData)
@@ -308,6 +444,7 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
     }
     qbsFileArtifact->fileTags.insert("qbs");
     artifactsPerFileTag["qbs"].insert(qbsFileArtifact);
+    product->registerAddedArtifact(qbsFileArtifact);
 
     // read sources
     foreach (const SourceArtifactConstPtr &sourceArtifact, product->allEnabledFiles()) {
@@ -316,6 +453,7 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
             continue; // ignore duplicate artifacts
 
         Artifact *artifact = createArtifact(product, sourceArtifact, m_logger);
+        product->registerAddedArtifact(artifact);
         foreach (const FileTag &fileTag, artifact->fileTags)
             artifactsPerFileTag[fileTag].insert(artifact);
     }
@@ -345,11 +483,12 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
             outputArtifact->artifactType = Artifact::Generated;
             outputArtifact->transformer = transformer;
             transformer->outputs += outputArtifact;
-            product->buildData->targetArtifacts += outputArtifact;
+            product->buildData->roots += outputArtifact;
             foreach (Artifact *inputArtifact, inputArtifacts)
                 safeConnect(outputArtifact, inputArtifact, m_logger);
             foreach (const FileTag &fileTag, outputArtifact->fileTags)
                 artifactsPerFileTag[fileTag].insert(outputArtifact);
+            product->registerAddedArtifact(outputArtifact);
 
             RuleArtifactPtr ruleArtifact = RuleArtifact::create();
             ruleArtifact->fileName = outputArtifact->filePath();
@@ -364,7 +503,7 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
         PrepareScriptObserver observer(engine());
         setupScriptEngineForProduct(engine(), product, transformer->rule, prepareScriptContext,
                                     &observer);
-        transformer->setupInputs(engine(), prepareScriptContext);
+        transformer->setupInputs(prepareScriptContext);
         transformer->setupOutputs(engine(), prepareScriptContext);
         transformer->createCommands(rtrafo->transform, evalContext(),
                 ScriptEngine::argumentList(transformer->rule->prepareScript->argumentNames,
@@ -387,8 +526,23 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
         }
     }
 
-    RulesApplicator(product, artifactsPerFileTag, m_logger).applyAllRules();
-    addTargetArtifacts(product, artifactsPerFileTag, m_logger);
+    RuleGraph ruleGraph;
+    ruleGraph.build(product->rules, product->fileTags);
+    CreateRuleNodes crn(product, m_logger);
+    ruleGraph.accept(&crn);
+
+    // Connect the leaf rules of this product to the root rules of all product dependencies.
+    foreach (const ResolvedProductConstPtr &dep, product->dependencies) {
+        if (!dep->buildData)
+            continue;
+        foreach (BuildGraphNode *depRoot, dep->buildData->roots) {
+            RuleNode *depRootRule = dynamic_cast<RuleNode *>(depRoot);
+            if (!depRootRule)
+                continue;
+            foreach (RuleNode *leafRule, crn.leaves())
+                loggedConnect(leafRule, depRootRule, m_logger);
+        }
+    }
 }
 
 RulesEvaluationContextPtr BuildDataResolver::evalContext() const
diff --git a/src/lib/corelib/buildgraph/projectbuilddata.h b/src/lib/corelib/buildgraph/projectbuilddata.h
index efc756428..afbd363d5 100644
--- a/src/lib/corelib/buildgraph/projectbuilddata.h
+++ b/src/lib/corelib/buildgraph/projectbuilddata.h
@@ -29,7 +29,6 @@
 #ifndef QBS_PROJECTBUILDDATA_H
 #define QBS_PROJECTBUILDDATA_H
 
-#include "artifactset.h"
 #include "forward_decls.h"
 #include <language/forward_decls.h>
 #include <logging/logger.h>
@@ -43,6 +42,8 @@
 
 namespace qbs {
 namespace Internal {
+class ArtifactSet;
+class BuildGraphNode;
 class FileDependency;
 class FileResourceBase;
 class ScriptEngine;
@@ -62,21 +63,21 @@ public:
     QList<FileResourceBase *> lookupFiles(const QString &dirPath, const QString &fileName) const;
     QList<FileResourceBase *> lookupFiles(const Artifact *artifact) const;
     void insertFileDependency(FileDependency *dependency);
-    void updateNodesThatMustGetNewTransformer(const Logger &logger);
     void removeArtifactAndExclusiveDependents(Artifact *artifact, const Logger &logger,
             bool removeFromProduct = true, ArtifactSet *removedArtifacts = 0);
     void removeArtifact(Artifact *artifact, const Logger &logger, bool removeFromDisk = true,
                         bool removeFromProduct = true);
 
+
     QSet<FileDependency *> fileDependencies;
+
+    // do not serialize:
     RulesEvaluationContextPtr evaluationContext;
-    QSet<Artifact *> artifactsThatMustGetNewTransformers;
     bool isDirty;
 
 private:
     void load(PersistentPool &pool);
     void store(PersistentPool &pool) const;
-    void updateNodeThatMustGetNewTransformer(Artifact *artifact, const Logger &logger);
 
     typedef QHash<QString, QList<FileResourceBase *> > ResultsPerDirectory;
     typedef QHash<QString, ResultsPerDirectory> ArtifactLookupTable;
@@ -95,6 +96,7 @@ public:
             const QList<ResolvedProductPtr> &freshProducts);
 
 private:
+    void resolveProductBuildDataForExistingProject(const ResolvedProductPtr &product);
     void resolveProductBuildData(const ResolvedProductPtr &product);
     RulesEvaluationContextPtr evalContext() const;
     ScriptEngine *engine() const;
diff --git a/src/lib/corelib/buildgraph/qtmocscanner.cpp b/src/lib/corelib/buildgraph/qtmocscanner.cpp
new file mode 100644
index 000000000..995250441
--- /dev/null
+++ b/src/lib/corelib/buildgraph/qtmocscanner.cpp
@@ -0,0 +1,189 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "qtmocscanner.h"
+
+#include "artifact.h"
+#include "productbuilddata.h"
+#include "scanresultcache.h"
+#include <tools/qbsassert.h>
+#include <tools/scannerpluginmanager.h>
+#include <tools/scripttools.h>
+
+#include <QScriptContext>
+#include <QScriptEngine>
+#include <QDebug>
+
+namespace qbs {
+namespace Internal {
+
+QtMocScanner::QtMocScanner(const ResolvedProductPtr &product, QScriptValue targetScriptValue,
+        const Logger &logger)
+    : m_product(product)
+    , m_targetScriptValue(targetScriptValue)
+    , m_logger(logger)
+    , m_scanResultCache(new ScanResultCache)
+    , m_cppScanner(0)
+    , m_hppScanner(0)
+{
+    QScriptEngine *engine = targetScriptValue.engine();
+    QScriptValue scannerObj = engine->newObject();
+    targetScriptValue.setProperty(QLatin1String("QtMocScanner"), scannerObj);
+    QScriptValue applyFunction = engine->newFunction(&js_apply, this);
+    scannerObj.setProperty(QLatin1String("apply"), applyFunction);
+}
+
+QtMocScanner::~QtMocScanner()
+{
+    m_targetScriptValue.setProperty(QLatin1String("QtMocScanner"), QScriptValue());
+    delete m_scanResultCache;
+}
+
+static ScanResultCache::Result runScanner(ScannerPlugin *scanner, const Artifact *artifact,
+        ScanResultCache *scanResultCache)
+{
+    ScanResultCache::Result scanResult = scanResultCache->value(artifact->filePath());
+    if (!scanResult.valid) {
+        scanResult.valid = true;
+        void *opaq = scanner->open(artifact->filePath().utf16(),
+                                   ScanForDependenciesFlag | ScanForFileTagsFlag);
+        if (!opaq || !scanner->additionalFileTags)
+            return scanResult;
+
+        int length = 0;
+        const char **szFileTagsFromScanner = scanner->additionalFileTags(opaq, &length);
+        if (szFileTagsFromScanner) {
+            for (int i = length; --i >= 0;)
+                scanResult.additionalFileTags += szFileTagsFromScanner[i];
+        }
+
+        forever {
+            int flags = 0;
+            const char *szOutFilePath = scanner->next(opaq, &length, &flags);
+            if (szOutFilePath == 0)
+                break;
+            QString includedFilePath = QString::fromLocal8Bit(szOutFilePath, length);
+            if (includedFilePath.isEmpty())
+                continue;
+            bool isLocalInclude = (flags & SC_LOCAL_INCLUDE_FLAG);
+            scanResult.deps += ScanResultCache::Dependency(includedFilePath, isLocalInclude);
+        }
+
+        scanner->close(opaq);
+        scanResultCache->insert(artifact->filePath(), scanResult);
+    }
+    return scanResult;
+}
+
+void QtMocScanner::findIncludedMocCppFiles()
+{
+    if (!m_includedMocCppFiles.isEmpty())
+        return;
+
+    if (m_logger.traceEnabled())
+        m_logger.qbsTrace() << "[QtMocScanner] looking for included moc_XXX.cpp files";
+
+    foreach (Artifact *artifact, m_product->lookupArtifactsByFileTag("cpp")) {
+        const ScanResultCache::Result scanResult
+                = runScanner(m_cppScanner, artifact, m_scanResultCache);
+        foreach (const ScanResultCache::Dependency &dependency, scanResult.deps) {
+            QString includedFilePath = dependency.filePath();
+            if (includedFilePath.startsWith("moc_") && includedFilePath.endsWith(".cpp")) {
+                if (m_logger.traceEnabled())
+                    m_logger.qbsTrace() << "[QtMocScanner] " << artifact->fileName()
+                                        << " includes " << includedFilePath;
+                includedFilePath.remove(0, 4);
+                includedFilePath.chop(4);
+                m_includedMocCppFiles.insert(includedFilePath, artifact->fileName());
+            }
+        }
+    }
+}
+
+QScriptValue QtMocScanner::js_apply(QScriptContext *ctx, QScriptEngine *engine, void *data)
+{
+    QtMocScanner *that = reinterpret_cast<QtMocScanner *>(data);
+    QScriptValue input = ctx->argument(0);
+    return that->apply(engine, attachedPointer<Artifact>(input));
+}
+
+QScriptValue QtMocScanner::apply(QScriptEngine *engine, const Artifact *artifact)
+{
+    if (!m_cppScanner) {
+        QList<ScannerPlugin *> scanners = ScannerPluginManager::scannersForFileTag("cpp");
+        QBS_CHECK(scanners.count() == 1);
+        m_cppScanner = scanners.first();
+        scanners = ScannerPluginManager::scannersForFileTag("hpp");
+        QBS_CHECK(scanners.count() == 1);
+        m_hppScanner = scanners.first();
+    }
+
+    findIncludedMocCppFiles();
+
+    if (m_logger.traceEnabled())
+        m_logger.qbsTrace() << "[QtMocScanner] scanning " << artifact->toString();
+
+    bool hasQObjectMacro = false;
+    bool mustCompile = false;
+    bool hasPluginMetaDataMacro = false;
+    const bool isHeaderFile = artifact->fileTags.contains("hpp");
+
+    ScannerPlugin * const scanner = isHeaderFile ? m_hppScanner : m_cppScanner;
+    const ScanResultCache::Result scanResult = runScanner(scanner, artifact, m_scanResultCache);
+    if (!scanResult.additionalFileTags.isEmpty()) {
+        if (isHeaderFile) {
+            if (scanResult.additionalFileTags.contains("moc_hpp"))
+                hasQObjectMacro = true;
+            if (scanResult.additionalFileTags.contains("moc_hpp_plugin")) {
+                hasQObjectMacro = true;
+                hasPluginMetaDataMacro = true;
+            }
+            if (!m_includedMocCppFiles.contains(FileInfo::completeBaseName(artifact->fileName())))
+                mustCompile = true;
+        } else {
+            if (scanResult.additionalFileTags.contains("moc_cpp"))
+                hasQObjectMacro = true;
+        }
+    }
+
+    if (m_logger.traceEnabled()) {
+        m_logger.qbsTrace() << "[QtMocScanner] hasQObjectMacro: " << hasQObjectMacro
+                            << " mustCompile: " << mustCompile
+                            << " hasPluginMetaDataMacro: " << hasPluginMetaDataMacro;
+    }
+
+    QScriptValue obj = engine->newObject();
+    obj.setProperty(QLatin1String("hasQObjectMacro"), hasQObjectMacro);
+    obj.setProperty(QLatin1String("mustCompile"), mustCompile);
+    obj.setProperty(QLatin1String("hasPluginMetaDataMacro"), hasPluginMetaDataMacro);
+    return obj;
+}
+
+} // namespace Internal
+} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/automoc.h b/src/lib/corelib/buildgraph/qtmocscanner.h
index d57fc292e..60983fe06 100644
--- a/src/lib/corelib/buildgraph/automoc.h
+++ b/src/lib/corelib/buildgraph/qtmocscanner.h
@@ -27,69 +27,50 @@
 **
 ****************************************************************************/
 
-#ifndef QBS_AUTOMOC_H
-#define QBS_AUTOMOC_H
+#ifndef QBS_QTMOCSCANNER_H
+#define QBS_QTMOCSCANNER_H
 
-#include "forward_decls.h"
-
-#include <language/forward_decls.h>
+#include <language/language.h>
 #include <logging/logger.h>
 
-#include <QObject>
+#include <QHash>
+#include <QScriptValue>
+#include <QString>
+
+QT_BEGIN_NAMESPACE
+class QScriptContext;
+QT_END_NAMESPACE
 
-struct ScannerPlugin;
+class ScannerPlugin;
 
 namespace qbs {
 namespace Internal {
-class FileTag;
+
+class Artifact;
 class ScanResultCache;
 
-/**
-  * Scans cpp and hpp files for the Q_OBJECT / Q_GADGET macro and
-  * applies the corresponding rule then.
-  * Also scans the files for moc_XXX.cpp files to find out if we must
-  * compile and link a moc_XXX.cpp file or not.
-  *
-  * This whole thing is an ugly hack, I know.
-  */
-class AutoMoc : public QObject
+class QtMocScanner
 {
-    Q_OBJECT
-
 public:
-    AutoMoc(const Logger &logger, QObject *parent = 0);
-
-    void setScanResultCache(ScanResultCache *scanResultCache);
-    void apply(const ResolvedProductPtr &product);
-
-signals:
-    void reportCommandDescription(const QString &highlight, const QString &message);
-
-private:
-    enum FileType
-    {
-        UnknownFileType,
-        HppFileType,
-        CppFileType
-    };
+    explicit QtMocScanner(const ResolvedProductPtr &product, QScriptValue targetScriptValue,
+            const Logger &logger);
+    ~QtMocScanner();
 
 private:
-    static QString generateMocFileName(Artifact *artifact, FileType fileType);
-    static FileType fileType(Artifact *artifact);
-    void scan(Artifact *artifact, FileType fileType, bool &hasQObjectMacro,
-            QSet<QString> &includedMocCppFiles);
-    bool isVictimOfMoc(Artifact *artifact, FileType fileType, FileTag &foundMocFileTag);
-    void unmoc(Artifact *artifact, const FileTag &mocFileTag);
-    const QList<ScannerPlugin *> &cppScanners() const;
-    const QList<ScannerPlugin *> &hppScanners() const;
+    void findIncludedMocCppFiles();
+    static QScriptValue js_apply(QScriptContext *ctx, QScriptEngine *engine, void *data);
+    QScriptValue apply(QScriptEngine *engine, const Artifact *artifact);
 
-    mutable QList<ScannerPlugin *> m_cppScanners;
-    mutable QList<ScannerPlugin *> m_hppScanners;
+    const ResolvedProductPtr &m_product;
+    QScriptValue m_targetScriptValue;
+    const Logger &m_logger;
     ScanResultCache *m_scanResultCache;
-    Logger m_logger;
+    QHash<QString, QString> m_includedMocCppFiles;
+    ScannerPlugin *m_cppScanner;
+    ScannerPlugin *m_hppScanner;
 };
 
 } // namespace Internal
 } // namespace qbs
 
-#endif // QBS_AUTOMOC_H
+#endif // QBS_QTMOCSCANNER_H
diff --git a/src/lib/corelib/buildgraph/rescuableartifactdata.cpp b/src/lib/corelib/buildgraph/rescuableartifactdata.cpp
new file mode 100644
index 000000000..314b84008
--- /dev/null
+++ b/src/lib/corelib/buildgraph/rescuableartifactdata.cpp
@@ -0,0 +1,70 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "rescuableartifactdata.h"
+
+#include "command.h"
+
+#include <tools/persistence.h>
+
+namespace qbs {
+namespace Internal {
+
+RescuableArtifactData::~RescuableArtifactData()
+{
+}
+
+void RescuableArtifactData::load(PersistentPool &pool)
+{
+    pool.stream() >> timeStamp;
+
+    int c;
+    pool.stream() >> c;
+    for (int i = 0; i < c; ++i) {
+        ChildData cd;
+        pool.stream() >> cd.productName >> cd.childFilePath >> cd.addedByScanner;
+        children << cd;
+    }
+
+    commands = loadCommandList(pool.stream());
+}
+
+void RescuableArtifactData::store(PersistentPool &pool) const
+{
+    pool.stream() << timeStamp;
+
+    pool.stream() << children.count();
+    foreach (const ChildData &cd, children)
+        pool.stream() << cd.productName << cd.childFilePath << cd.addedByScanner;
+
+    storeCommandList(commands, pool.stream());
+}
+
+} // namespace Internal
+} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/rescuableartifactdata.h b/src/lib/corelib/buildgraph/rescuableartifactdata.h
new file mode 100644
index 000000000..9c93b1cce
--- /dev/null
+++ b/src/lib/corelib/buildgraph/rescuableartifactdata.h
@@ -0,0 +1,72 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QBS_RESCUABLEARTIFACTDATA_H
+#define QBS_RESCUABLEARTIFACTDATA_H
+
+#include "forward_decls.h"
+
+#include <tools/filetime.h>
+#include <tools/persistence.h>
+
+#include <QHash>
+#include <QList>
+
+namespace qbs {
+namespace Internal {
+
+class RescuableArtifactData : public PersistentObject
+{
+public:
+    ~RescuableArtifactData();
+
+    void load(PersistentPool &pool);
+    void store(PersistentPool &pool) const;
+
+    struct ChildData
+    {
+        ChildData(const QString &p = QString(), const QString &c = QString(),
+                  bool byScanner = false)
+            : productName(p), childFilePath(c), addedByScanner(byScanner)
+        {}
+        QString productName;
+        QString childFilePath;
+        bool addedByScanner;
+    };
+
+    FileTime timeStamp;
+    QList<ChildData> children;
+    QList<AbstractCommandPtr> commands;
+};
+typedef QHash<QString, RescuableArtifactData> AllRescuableArtifactData;
+
+} // namespace Internal
+} // namespace qbs
+
+#endif // Include guard.
diff --git a/src/lib/corelib/buildgraph/rulegraph.cpp b/src/lib/corelib/buildgraph/rulegraph.cpp
index 7a2e114c4..7098004ef 100644
--- a/src/lib/corelib/buildgraph/rulegraph.cpp
+++ b/src/lib/corelib/buildgraph/rulegraph.cpp
@@ -44,7 +44,7 @@ void RuleGraph::build(const QSet<RulePtr> &rules, const FileTags &productFileTag
     QMap<FileTag, QList<const Rule *> > inputFileTagToRule;
     m_artifacts.reserve(rules.count());
     foreach (const RulePtr &rule, rules) {
-        foreach (const FileTag &fileTag, rule->staticOutputFileTags())
+        foreach (const FileTag &fileTag, rule->collectedOutputFileTags())
             m_outputFileTagToRule[fileTag].append(rule.data());
         insert(rule);
     }
@@ -58,8 +58,11 @@ void RuleGraph::build(const QSet<RulePtr> &rules, const FileTags &productFileTag
         inFileTags += rule->explicitlyDependsOn;
         foreach (const FileTag &fileTag, inFileTags) {
             inputFileTagToRule[fileTag].append(rule.data());
-            foreach (const Rule * const consumingRule, m_outputFileTagToRule.value(fileTag)) {
-                connect(rule.data(), consumingRule);
+            foreach (const Rule * const producingRule, m_outputFileTagToRule.value(fileTag)) {
+                if (!producingRule->collectedOutputFileTags().matches(
+                        rule->excludedAuxiliaryInputs)) {
+                    connect(rule.data(), producingRule);
+                }
             }
         }
     }
@@ -74,30 +77,11 @@ void RuleGraph::build(const QSet<RulePtr> &rules, const FileTags &productFileTag
         m_rootRules += r->ruleGraphId;
 }
 
-QList<RuleConstPtr> RuleGraph::topSorted()
+void RuleGraph::accept(RuleGraphVisitor *visitor) const
 {
-    QSet<int> rootRules = m_rootRules;
-    QList<RuleConstPtr> result;
-    foreach (int rootIndex, rootRules) {
-        RuleConstPtr rule = m_artifacts.at(rootIndex);
-        QSet<const Rule *> seenRules;
-        QList<const Rule *> rulePath;
-        result.append(topSort(rule, &seenRules, &rulePath));
-    }
-
-    // remove duplicates from the result of our post-order traversal
-    QSet<const Rule*> seenRules;
-    seenRules.reserve(result.count());
-    for (int i = 0; i < result.count();) {
-        const Rule * const rule = result.at(i).data();
-        if (seenRules.contains(rule))
-            result.removeAt(i);
-        else
-            ++i;
-        seenRules.insert(rule);
-    }
-
-    return result;
+    const RuleConstPtr nullParent;
+    foreach (int rootIndex, m_rootRules)
+        traverse(visitor, nullParent, m_artifacts.at(rootIndex));
 }
 
 void RuleGraph::dump() const
@@ -145,29 +129,13 @@ void RuleGraph::connect(const Rule *creatingRule, const Rule *consumingRule)
     m_children[creatingRule->ruleGraphId].append(consumingRule->ruleGraphId);
 }
 
-QList<RuleConstPtr> RuleGraph::topSort(const RuleConstPtr &rule, QSet<const Rule *> *seenRules,
-        QList<const Rule *> *rulePath)
+void RuleGraph::traverse(RuleGraphVisitor *visitor, const RuleConstPtr &parentRule,
+        const RuleConstPtr &rule) const
 {
-    if (seenRules->contains(rule.data())) {
-        QString pathstr;
-        foreach (const Rule *r, *rulePath) {
-            pathstr += QLatin1Char('\n') + r->toString() + QLatin1Char('\t')
-                    + r->prepareScript->location.toString();
-        }
-        throw ErrorInfo(Tr::tr("Cycle detected in rule dependencies: %1").arg(pathstr));
-    }
-
-    seenRules->insert(rule.data());
-    rulePath->prepend(rule.data());
-
-    QList<RuleConstPtr> result;
+    visitor->visit(parentRule, rule);
     foreach (int childIndex, m_children.at(rule->ruleGraphId))
-        result.append(topSort(m_artifacts.at(childIndex), seenRules, rulePath));
-
-    result.append(rule);
-    seenRules->remove(rule.data());
-    rulePath->removeFirst();
-    return result;
+        traverse(visitor, rule, m_artifacts.at(childIndex));
+    visitor->endVisit(rule);
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/rulegraph.h b/src/lib/corelib/buildgraph/rulegraph.h
index 2f9a42a33..375224449 100644
--- a/src/lib/corelib/buildgraph/rulegraph.h
+++ b/src/lib/corelib/buildgraph/rulegraph.h
@@ -42,13 +42,20 @@
 namespace qbs {
 namespace Internal {
 
+class RuleGraphVisitor
+{
+public:
+    virtual void visit(const RuleConstPtr &parentRule, const RuleConstPtr &rule) = 0;
+    virtual void endVisit(const RuleConstPtr &rule) { Q_UNUSED(rule); }
+};
+
 class RuleGraph
 {
 public:
     RuleGraph();
 
     void build(const QSet<RulePtr> &rules, const FileTags &productFileTag);
-    QList<RuleConstPtr> topSorted();
+    void accept(RuleGraphVisitor *visitor) const;
 
     void dump() const;
 
@@ -56,8 +63,8 @@ private:
     void dump_impl(QByteArray &indent, int rootIndex) const;
     int insert(const RulePtr &rule);
     void connect(const Rule *creatingRule, const Rule *consumingRule);
-    QList<RuleConstPtr> topSort(const RuleConstPtr &rule, QSet<const Rule *> *seenRules,
-            QList<const Rule *> *rulePath);
+    void traverse(RuleGraphVisitor *visitor, const RuleConstPtr &parentRule,
+            const RuleConstPtr &rule) const;
 
 private:
     QMap<FileTag, QList<const Rule*> > m_outputFileTagToRule;
diff --git a/src/lib/corelib/buildgraph/rulenode.cpp b/src/lib/corelib/buildgraph/rulenode.cpp
new file mode 100644
index 000000000..3d79cdea3
--- /dev/null
+++ b/src/lib/corelib/buildgraph/rulenode.cpp
@@ -0,0 +1,144 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "rulenode.h"
+
+#include "artifact.h"
+#include "buildgraph.h"
+#include "buildgraphvisitor.h"
+#include "productbuilddata.h"
+#include "projectbuilddata.h"
+#include "rulesapplicator.h"
+#include "transformer.h"
+#include <language/language.h>
+#include <logging/logger.h>
+
+namespace qbs {
+namespace Internal {
+
+RuleNode::RuleNode()
+{
+}
+
+RuleNode::~RuleNode()
+{
+}
+
+void RuleNode::accept(BuildGraphVisitor *visitor)
+{
+    if (visitor->visit(this))
+        acceptChildren(visitor);
+}
+
+QString RuleNode::toString() const
+{
+    return QLatin1String("RULE ") + m_rule->toString();
+}
+
+void RuleNode::apply(const Logger &logger, const ArtifactSet &changedInputs,
+        ApplicationResult *result)
+{
+    bool hasAddedTags = false;
+    bool hasRemovedTags = false;
+    result->upToDate = changedInputs.isEmpty();
+
+    ProductBuildData::ArtifactSetByFileTag relevantArtifacts;
+    if (product->isMarkedForReapplication(m_rule)) {
+        QBS_CHECK(m_rule->multiplex);
+        result->upToDate = false;
+        product->unmarkForReapplication(m_rule);
+        if (logger.traceEnabled())
+            logger.qbsTrace() << "[BG] rule is marked for reapplication " << m_rule->toString();
+
+        foreach (Artifact *artifact, ArtifactSet::fromNodeSet(product->buildData->nodes)) {
+            if (m_rule->acceptsAsInput(artifact))
+                addArtifactToSet(artifact, relevantArtifacts);
+        }
+    } else {
+        foreach (const FileTag &tag, m_rule->inputs) {
+            if (product->addedArtifactsByFileTag(tag).count()) {
+                hasAddedTags = true;
+                result->upToDate = false;
+            }
+            if (product->removedArtifactsByFileTag(tag).count()) {
+                hasRemovedTags = true;
+                result->upToDate = false;
+            }
+            if (hasAddedTags && hasRemovedTags)
+                break;
+        }
+
+        relevantArtifacts = product->buildData->addedArtifactsByFileTag;
+        if (!changedInputs.isEmpty()) {
+            foreach (Artifact *artifact, changedInputs)
+                addArtifactToSet(artifact, relevantArtifacts);
+        }
+    }
+    if (result->upToDate)
+        return;
+    if (hasRemovedTags) {
+        ArtifactSet outputArtifactsToRemove;
+        foreach (const FileTag &tag, m_rule->inputs) {
+            foreach (Artifact *artifact, product->removedArtifactsByFileTag(tag)) {
+                foreach (Artifact *parent, ArtifactSet::fromNodeSet(artifact->parents)) {
+                    if (!parent->transformer || parent->transformer->rule != m_rule
+                            || !parent->transformer->inputs.contains(artifact)) {
+                        // parent was not created by our rule.
+                        continue;
+                    }
+                    outputArtifactsToRemove += parent;
+                }
+            }
+        }
+        RulesApplicator::handleRemovedRuleOutputs(outputArtifactsToRemove, logger);
+    }
+    if (!relevantArtifacts.isEmpty()) {
+        RulesApplicator applicator(product, relevantArtifacts, logger);
+        result->createdNodes = applicator.applyRuleInEvaluationContext(m_rule);
+        foreach (BuildGraphNode *node, result->createdNodes) {
+            if (Artifact *artifact = dynamic_cast<Artifact *>(node))
+                product->registerAddedArtifact(artifact);
+        }
+    }
+}
+
+void RuleNode::load(PersistentPool &pool)
+{
+    BuildGraphNode::load(pool);
+    m_rule = pool.idLoadS<Rule>();
+}
+
+void RuleNode::store(PersistentPool &pool) const
+{
+    BuildGraphNode::store(pool);
+    pool.store(m_rule);
+}
+
+} // namespace Internal
+} // namespace qbs
diff --git a/src/lib/corelib/buildgraph/rulenode.h b/src/lib/corelib/buildgraph/rulenode.h
new file mode 100644
index 000000000..b4f17a405
--- /dev/null
+++ b/src/lib/corelib/buildgraph/rulenode.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt Build Suite.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef QBS_RULENODE_H
+#define QBS_RULENODE_H
+
+#include "artifactset.h"
+#include "buildgraphnode.h"
+#include <language/forward_decls.h>
+
+#include <QVector>
+
+namespace qbs {
+namespace Internal {
+
+class Logger;
+
+class RuleNode : public BuildGraphNode
+{
+public:
+    RuleNode();
+    ~RuleNode();
+
+    void setRule(const RuleConstPtr &rule) { m_rule = rule; }
+    const RuleConstPtr &rule() const { return m_rule; }
+
+    Type type() const { return RuleNodeType; }
+    void accept(BuildGraphVisitor *visitor);
+    QString toString() const;
+
+    struct ApplicationResult
+    {
+        bool upToDate;
+        QVector<BuildGraphNode *> createdNodes;
+    };
+
+    void apply(const Logger &logger, const ArtifactSet &changedInputs, ApplicationResult *result);
+
+protected:
+    void load(PersistentPool &pool);
+    void store(PersistentPool &pool) const;
+
+private:
+    RuleConstPtr m_rule;
+};
+
+} // namespace Internal
+} // namespace qbs
+
+#endif // QBS_RULENODE_H
diff --git a/src/lib/corelib/buildgraph/rulesapplicator.cpp b/src/lib/corelib/buildgraph/rulesapplicator.cpp
index 70dce38c1..43c4efb45 100644
--- a/src/lib/corelib/buildgraph/rulesapplicator.cpp
+++ b/src/lib/corelib/buildgraph/rulesapplicator.cpp
@@ -32,6 +32,7 @@
 #include "buildgraph.h"
 #include "productbuilddata.h"
 #include "projectbuilddata.h"
+#include "qtmocscanner.h"
 #include "rulesevaluationcontext.h"
 #include "transformer.h"
 #include <jsextensions/moduleproperties.h>
@@ -53,20 +54,31 @@ RulesApplicator::RulesApplicator(const ResolvedProductPtr &product,
                                  ArtifactsPerFileTagMap &artifactsPerFileTag, const Logger &logger)
     : m_product(product)
     , m_artifactsPerFileTag(artifactsPerFileTag)
+    , m_mocScanner(0)
     , m_logger(logger)
 {
 }
 
-void RulesApplicator::applyAllRules()
+RulesApplicator::~RulesApplicator()
 {
+    delete m_mocScanner;
+}
+
+QVector<BuildGraphNode *> RulesApplicator::applyRuleInEvaluationContext(const RuleConstPtr &rule)
+{
+    m_createdArtifacts.clear();
     RulesEvaluationContext::Scope s(m_product->topLevelProject()->buildData->evaluationContext.data());
-    foreach (const RuleConstPtr &rule, m_product->topSortedRules())
-        applyRule(rule);
+    applyRule(rule);
+    return m_createdArtifacts;
 }
 
 void RulesApplicator::applyRule(const RuleConstPtr &rule)
 {
     m_rule = rule;
+    if (rule->name == QLatin1String("QtCoreMocRule")) {
+        delete m_mocScanner;
+        m_mocScanner = new QtMocScanner(m_product, scope(), m_logger);
+    }
     QScriptValue prepareScriptContext = engine()->newObject();
     PrepareScriptObserver observer(engine());
     setupScriptEngineForFile(engine(), m_rule->prepareScript->fileContext, scope());
@@ -89,13 +101,44 @@ void RulesApplicator::applyRule(const RuleConstPtr &rule)
     }
 }
 
+void RulesApplicator::handleRemovedRuleOutputs(ArtifactSet outputArtifactsToRemove,
+        const Logger &logger)
+{
+    ArtifactSet artifactsToRemove;
+    foreach (Artifact *removedArtifact, outputArtifactsToRemove) {
+        if (logger.traceEnabled()) {
+            logger.qbsTrace() << "[BG] dynamic rule removed output artifact "
+                                << removedArtifact->toString();
+        }
+        removedArtifact->product->topLevelProject()
+                ->buildData->removeArtifactAndExclusiveDependents(removedArtifact, logger, true,
+                                                                  &artifactsToRemove);
+    }
+    // parents of removed artifacts must update their transformers
+    foreach (Artifact *removedArtifact, artifactsToRemove) {
+        foreach (Artifact *parent, removedArtifact->parentArtifacts())
+            parent->product->registerArtifactWithChangedInputs(parent);
+    }
+    qDeleteAll(artifactsToRemove);
+}
+
 static void copyProperty(const QString &name, const QScriptValue &src, QScriptValue dst)
 {
     dst.setProperty(name, src.property(name));
 }
 
-void RulesApplicator::doApply(const ArtifactSet &inputArtifacts,
-    QScriptValue &prepareScriptContext)
+static QStringList toStringList(const ArtifactSet &artifacts)
+{
+    QStringList lst;
+    foreach (const Artifact *artifact, artifacts) {
+        const QString str = artifact->filePath() + QLatin1String(" [")
+                + artifact->fileTags.toStringList().join(QLatin1String(", ")) + QLatin1Char(']');
+        lst << str;
+    }
+    return lst;
+}
+
+void RulesApplicator::doApply(ArtifactSet inputArtifacts, QScriptValue &prepareScriptContext)
 {
     evalContext()->checkForCancelation();
 
@@ -108,31 +151,49 @@ void RulesApplicator::doApply(const ArtifactSet &inputArtifacts,
     QList<QPair<const RuleArtifact *, Artifact *> > ruleArtifactArtifactMap;
     QList<Artifact *> outputArtifacts;
 
-    ArtifactSet usingArtifacts;
     if (!m_rule->usings.isEmpty()) {
         const FileTags usingsFileTags = m_rule->usings;
         foreach (const ResolvedProductPtr &dep, m_product->dependencies) {
             QBS_CHECK(dep->buildData);
             ArtifactSet artifactsToCheck;
-            foreach (Artifact *targetArtifact, dep->buildData->targetArtifacts)
+            foreach (Artifact *targetArtifact, dep->buildData->targetArtifacts())
                 artifactsToCheck.unite(targetArtifact->transformer->outputs);
             foreach (Artifact *artifact, artifactsToCheck) {
                 if (artifact->fileTags.matches(usingsFileTags))
-                    usingArtifacts.insert(artifact);
+                    inputArtifacts.insert(artifact);
             }
         }
     }
 
     m_transformer.clear();
     // create the output artifacts from the set of input artifacts
+    Transformer::setupInputs(prepareScriptContext, inputArtifacts, m_rule->module->name);
+    copyProperty(QLatin1String("inputs"), prepareScriptContext, scope());
+    if (m_rule->multiplex) {
+        // ### awful! Revisit how the "input" property is set up!
+        copyProperty(QLatin1String("input"), prepareScriptContext, scope());
+    }
     copyProperty(QLatin1String("product"), prepareScriptContext, scope());
     copyProperty(QLatin1String("project"), prepareScriptContext, scope());
-    foreach (const RuleArtifactConstPtr &ruleArtifact, m_rule->artifacts) {
-        Artifact * const outputArtifact = createOutputArtifact(ruleArtifact, inputArtifacts);
-        outputArtifacts << outputArtifact;
-        ruleArtifactArtifactMap << qMakePair(ruleArtifact.data(), outputArtifact);
+    if (m_rule->isDynamic()) {
+        outputArtifacts = runOutputArtifactsScript(inputArtifacts,
+                    ScriptEngine::argumentList(m_rule->outputArtifactsScript->argumentNames,
+                                               scope()));
+        ArtifactSet newOutputs = ArtifactSet::fromNodeList(outputArtifacts);
+        const ArtifactSet oldOutputs = collectOldOutputArtifacts(inputArtifacts);
+        handleRemovedRuleOutputs(oldOutputs - newOutputs, m_logger);
+    } else {
+        foreach (const RuleArtifactConstPtr &ruleArtifact, m_rule->artifacts) {
+            Artifact * const outputArtifact
+                    = createOutputArtifactFromRuleArtifact(ruleArtifact, inputArtifacts);
+            outputArtifacts << outputArtifact;
+            ruleArtifactArtifactMap << qMakePair(ruleArtifact.data(), outputArtifact);
+        }
     }
 
+    if (outputArtifacts.isEmpty())
+        return;
+
     foreach (Artifact *outputArtifact, outputArtifacts) {
         // insert the output artifacts into the pool of artifacts
         foreach (const FileTag &fileTag, outputArtifact->fileTags)
@@ -143,21 +204,12 @@ void RulesApplicator::doApply(const ArtifactSet &inputArtifacts,
             foreach (Artifact *dependency, m_artifactsPerFileTag.value(fileTag))
                 loggedConnect(outputArtifact, dependency, m_logger);
 
-        // Transformer setup
-        for (ArtifactSet::const_iterator it = usingArtifacts.constBegin();
-             it != usingArtifacts.constEnd(); ++it)
-        {
-            Artifact *dep = *it;
-            loggedConnect(outputArtifact, dep, m_logger);
-            m_transformer->inputs.insert(dep);
-        }
         m_transformer->outputs.insert(outputArtifact);
-
-        m_product->topLevelProject()->buildData->artifactsThatMustGetNewTransformers
-                -= outputArtifact;
+        outputArtifact->product->unregisterArtifactWithChangedInputs(outputArtifact);
     }
 
-    m_transformer->setupInputs(engine(), prepareScriptContext);
+    if (inputArtifacts != m_transformer->inputs)
+        m_transformer->setupInputs(prepareScriptContext);
 
     // change the transformer outputs according to the bindings in Artifact
     QScriptValue scriptValue;
@@ -227,21 +279,44 @@ void RulesApplicator::setupScriptEngineForArtifact(Artifact *artifact)
     scriptValue.setProperty(QLatin1String("baseName"), inBaseName);
     scriptValue.setProperty(QLatin1String("completeBaseName"), inCompleteBaseName);
     scriptValue.setProperty(QLatin1String("baseDir"), basedir);
+    scriptValue.setProperty(QLatin1String("fileTags"),
+            engine()->toScriptValue(artifact->fileTags.toStringList()));
+    attachPointerTo(scriptValue, artifact);
 
     scope().setProperty(QLatin1String("input"), scriptValue);
     Q_ASSERT_X(scriptValue.strictlyEquals(engine()->evaluate(QLatin1String("input"))),
                "BG", "The input object is not in current scope.");
 }
 
-Artifact *RulesApplicator::createOutputArtifact(const RuleArtifactConstPtr &ruleArtifact,
-        const ArtifactSet &inputArtifacts)
+ArtifactSet RulesApplicator::collectOldOutputArtifacts(const ArtifactSet &inputArtifacts) const
+{
+    ArtifactSet result;
+    foreach (Artifact *a, inputArtifacts) {
+        foreach (Artifact *p, a->parentArtifacts()) {
+            QBS_CHECK(p->transformer);
+            if (p->transformer->rule == m_rule && p->transformer->inputs.contains(a))
+                result += p;
+        }
+    }
+    return result;
+}
+
+Artifact *RulesApplicator::createOutputArtifactFromRuleArtifact(
+        const RuleArtifactConstPtr &ruleArtifact, const ArtifactSet &inputArtifacts)
 {
     QScriptValue scriptValue = engine()->evaluate(ruleArtifact->fileName);
     if (Q_UNLIKELY(engine()->hasErrorOrException(scriptValue)))
         throw ErrorInfo(Tr::tr("Error in Rule.Artifact fileName: ") + scriptValue.toString());
     QString outputPath = scriptValue.toString();
+    return createOutputArtifact(outputPath, ruleArtifact->fileTags, ruleArtifact->alwaysUpdated,
+                                inputArtifacts);
+}
 
-    // Don't let the output artifact "escape" its build dir
+Artifact *RulesApplicator::createOutputArtifact(const QString &filePath, const FileTags &fileTags,
+        bool alwaysUpdated, const ArtifactSet &inputArtifacts)
+{
+    QString outputPath = filePath;
+    // don't let the output artifact "escape" its build dir
     outputPath.replace(QLatin1String(".."), QLatin1String("dotdot"));
     outputPath = resolveOutPath(outputPath);
 
@@ -288,15 +363,17 @@ Artifact *RulesApplicator::createOutputArtifact(const RuleArtifactConstPtr &rule
                 throw ErrorInfo(e);
             }
         }
-        outputArtifact->fileTags += ruleArtifact->fileTags;
+        outputArtifact->fileTags += fileTags;
+        outputArtifact->clearTimestamp();
     } else {
         outputArtifact = new Artifact;
         outputArtifact->artifactType = Artifact::Generated;
         outputArtifact->setFilePath(outputPath);
-        outputArtifact->fileTags = ruleArtifact->fileTags;
-        outputArtifact->alwaysUpdated = ruleArtifact->alwaysUpdated;
+        outputArtifact->fileTags = fileTags;
+        outputArtifact->alwaysUpdated = alwaysUpdated;
         outputArtifact->properties = m_product->properties;
         insertArtifact(m_product, outputArtifact, m_logger);
+        m_createdArtifacts += outputArtifact;
     }
 
     if (outputArtifact->fileTags.isEmpty())
@@ -326,6 +403,47 @@ Artifact *RulesApplicator::createOutputArtifact(const RuleArtifactConstPtr &rule
     return outputArtifact;
 }
 
+QList<Artifact *> RulesApplicator::runOutputArtifactsScript(const ArtifactSet &inputArtifacts,
+        const QScriptValueList &args)
+{
+    QList<Artifact *> lst;
+    QScriptValue fun = engine()->evaluate(m_rule->outputArtifactsScript->sourceCode);
+    if (!fun.isFunction())
+        throw ErrorInfo(QLatin1String("Function expected."),
+                        m_rule->outputArtifactsScript->location);
+    QScriptValue res = fun.call(QScriptValue(), args);
+    if (res.isError() || engine()->hasUncaughtException())
+        throw ErrorInfo(Tr::tr("Error while calling Rule.outputArtifacts: %1").arg(res.toString()),
+                        m_rule->outputArtifactsScript->location);
+    if (!res.isArray())
+        throw ErrorInfo(Tr::tr("Rule.outputArtifacts must return an array of objects."),
+                        m_rule->outputArtifactsScript->location);
+    const quint32 c = res.property(QLatin1String("length")).toUInt32();
+    for (quint32 i = 0; i < c; ++i)
+        lst += createOutputArtifactFromScriptValue(res.property(i), inputArtifacts);
+    return lst;
+}
+
+Artifact *RulesApplicator::createOutputArtifactFromScriptValue(const QScriptValue &obj,
+        const ArtifactSet &inputArtifacts)
+{
+    QBS_CHECK(obj.isObject());
+    const QString filePath = obj.property(QLatin1String("filePath")).toVariant().toString();
+    const FileTags fileTags = FileTags::fromStringList(
+                obj.property(QLatin1String("fileTags")).toVariant().toStringList());
+    const QVariant alwaysUpdatedVar = obj.property(QLatin1String("alwaysUpdated")).toVariant();
+    const bool alwaysUpdated = alwaysUpdatedVar.isValid() ? alwaysUpdatedVar.toBool() : true;
+    Artifact *output = createOutputArtifact(filePath, fileTags, alwaysUpdated, inputArtifacts);
+    const FileTags explicitlyDependsOn = FileTags::fromStringList(
+                obj.property(QLatin1String("explicitlyDependsOn")).toVariant().toStringList());
+    foreach (const FileTag &tag, explicitlyDependsOn) {
+        foreach (Artifact *dependency, m_product->lookupArtifactsByFileTag(tag)) {
+            loggedConnect(output, dependency, m_logger);
+        }
+    }
+    return output;
+}
+
 QString RulesApplicator::resolveOutPath(const QString &path) const
 {
     QString buildDir = m_product->topLevelProject()->buildDirectory;
diff --git a/src/lib/corelib/buildgraph/rulesapplicator.h b/src/lib/corelib/buildgraph/rulesapplicator.h
index 9ea54dfe7..e5813834a 100644
--- a/src/lib/corelib/buildgraph/rulesapplicator.h
+++ b/src/lib/corelib/buildgraph/rulesapplicator.h
@@ -35,29 +35,41 @@
 #include <language/forward_decls.h>
 #include <logging/logger.h>
 
-#include <QMap>
+#include <QHash>
 #include <QScriptValue>
 #include <QString>
+#include <QVector>
 
 namespace qbs {
 namespace Internal {
+class BuildGraphNode;
+class QtMocScanner;
 class ScriptEngine;
 
-typedef QMap<FileTag, ArtifactSet> ArtifactsPerFileTagMap;
+typedef QHash<FileTag, ArtifactSet> ArtifactsPerFileTagMap;
 
 class RulesApplicator
 {
 public:
     RulesApplicator(const ResolvedProductPtr &product, ArtifactsPerFileTagMap &artifactsPerFileTag,
                     const Logger &logger);
-    void applyAllRules();
+    ~RulesApplicator();
+    QVector<BuildGraphNode *> applyRuleInEvaluationContext(const RuleConstPtr &rule);
     void applyRule(const RuleConstPtr &rule);
+    static void handleRemovedRuleOutputs(ArtifactSet artifactsToRemove, const Logger &logger);
 
 private:
-    void doApply(const ArtifactSet &inputArtifacts, QScriptValue &prepareScriptContext);
+    void doApply(ArtifactSet inputArtifacts, QScriptValue &prepareScriptContext);
     void setupScriptEngineForArtifact(Artifact *artifact);
-    Artifact *createOutputArtifact(const RuleArtifactConstPtr &ruleArtifact,
-                                   const ArtifactSet &inputArtifacts);
+    ArtifactSet collectOldOutputArtifacts(const ArtifactSet &inputArtifacts) const;
+    Artifact *createOutputArtifactFromRuleArtifact(const RuleArtifactConstPtr &ruleArtifact,
+            const ArtifactSet &inputArtifacts);
+    Artifact *createOutputArtifact(const QString &filePath, const FileTags &fileTags,
+            bool alwaysUpdated, const ArtifactSet &inputArtifacts);
+    QList<Artifact *> runOutputArtifactsScript(const ArtifactSet &inputArtifacts,
+            const QScriptValueList &args);
+    Artifact *createOutputArtifactFromScriptValue(const QScriptValue &obj,
+            const ArtifactSet &inputArtifacts);
     QString resolveOutPath(const QString &path) const;
     RulesEvaluationContextPtr evalContext() const;
     ScriptEngine *engine() const;
@@ -65,9 +77,11 @@ private:
 
     const ResolvedProductPtr m_product;
     ArtifactsPerFileTagMap &m_artifactsPerFileTag;
+    QVector<BuildGraphNode *>  m_createdArtifacts;
 
     RuleConstPtr m_rule;
     TransformerPtr m_transformer;
+    QtMocScanner *m_mocScanner;
     Logger m_logger;
 };
 
diff --git a/src/lib/corelib/buildgraph/timestampsupdater.cpp b/src/lib/corelib/buildgraph/timestampsupdater.cpp
index c22e9f96c..2ba6bc8ee 100644
--- a/src/lib/corelib/buildgraph/timestampsupdater.cpp
+++ b/src/lib/corelib/buildgraph/timestampsupdater.cpp
@@ -54,7 +54,7 @@ public:
 
         // For target artifacts, we have to update the on-disk timestamp, because
         // the executor will look at it.
-        foreach (Artifact * const targetArtifact, product->buildData->targetArtifacts) {
+        foreach (Artifact * const targetArtifact, product->buildData->targetArtifacts()) {
             if (FileInfo(targetArtifact->filePath()).exists())
                 QFile(targetArtifact->filePath()).open(QIODevice::WriteOnly | QIODevice::Append);
         }
diff --git a/src/lib/corelib/buildgraph/transformer.cpp b/src/lib/corelib/buildgraph/transformer.cpp
index becb110ba..011ff0fb0 100644
--- a/src/lib/corelib/buildgraph/transformer.cpp
+++ b/src/lib/corelib/buildgraph/transformer.cpp
@@ -48,7 +48,6 @@ Transformer::Transformer()
 
 Transformer::~Transformer()
 {
-    qDeleteAll(commands);
 }
 
 QScriptValue Transformer::translateFileConfig(QScriptEngine *scriptEngine, Artifact *artifact, const QString &defaultModuleName)
@@ -92,9 +91,10 @@ ResolvedProductPtr Transformer::product() const
     return (*outputs.begin())->product;
 }
 
-void Transformer::setupInputs(QScriptEngine *scriptEngine, QScriptValue targetScriptValue)
+void Transformer::setupInputs(QScriptValue targetScriptValue, const ArtifactSet &inputs,
+        const QString &defaultModuleName)
 {
-    const QString &defaultModuleName = rule->module->name;
+    QScriptEngine *const scriptEngine = targetScriptValue.engine();
     QScriptValue scriptValue = translateInOutputs(scriptEngine, inputs, defaultModuleName);
     targetScriptValue.setProperty(QLatin1String("inputs"), scriptValue);
     if (inputs.count() == 1) {
@@ -109,6 +109,11 @@ void Transformer::setupInputs(QScriptEngine *scriptEngine, QScriptValue targetSc
     }
 }
 
+void Transformer::setupInputs(QScriptValue targetScriptValue)
+{
+    setupInputs(targetScriptValue, inputs, rule->module->name);
+}
+
 void Transformer::setupOutputs(QScriptEngine *scriptEngine, QScriptValue targetScriptValue)
 {
     const QString &defaultModuleName = rule->module->name;
@@ -126,17 +131,17 @@ void Transformer::setupOutputs(QScriptEngine *scriptEngine, QScriptValue targetS
     }
 }
 
-static AbstractCommand *createCommandFromScriptValue(const QScriptValue &scriptValue,
-                                                     const CodeLocation &codeLocation)
+static AbstractCommandPtr createCommandFromScriptValue(const QScriptValue &scriptValue,
+                                                       const CodeLocation &codeLocation)
 {
+    AbstractCommandPtr cmdBase;
     if (scriptValue.isUndefined() || !scriptValue.isValid())
-        return 0;
-    AbstractCommand *cmdBase = 0;
+        return cmdBase;
     QString className = scriptValue.property(QLatin1String("className")).toString();
     if (className == QLatin1String("Command"))
-        cmdBase = new ProcessCommand;
+        cmdBase = ProcessCommand::create();
     else if (className == QLatin1String("JavaScriptCommand"))
-        cmdBase = new JavaScriptCommand;
+        cmdBase = JavaScriptCommand::create();
     if (cmdBase)
         cmdBase->fillFromScriptValue(&scriptValue, codeLocation);
     return cmdBase;
@@ -162,20 +167,19 @@ void Transformer::createCommands(const ScriptFunctionConstPtr &script,
                     CodeLocation(script->location.fileName(),
                                  script->location.line() + engine->uncaughtExceptionLineNumber() - 1));
 
-    qDeleteAll(commands);
     commands.clear();
     if (scriptValue.isArray()) {
         const int count = scriptValue.property(QLatin1String("length")).toInt32();
         for (qint32 i = 0; i < count; ++i) {
             QScriptValue item = scriptValue.property(i);
             if (item.isValid() && !item.isUndefined()) {
-                AbstractCommand *cmd = createCommandFromScriptValue(item, script->location);
+                const AbstractCommandPtr cmd = createCommandFromScriptValue(item, script->location);
                 if (cmd)
                     commands += cmd;
             }
         }
     } else {
-        AbstractCommand *cmd = createCommandFromScriptValue(scriptValue, script->location);
+        const AbstractCommandPtr cmd = createCommandFromScriptValue(scriptValue, script->location);
         if (cmd)
             commands += cmd;
     }
@@ -223,15 +227,7 @@ void Transformer::load(PersistentPool &pool)
         }
         propertiesRequestedFromArtifactInPrepareScript.insert(artifactName, list);
     }
-    int cmdType;
-    pool.stream() >> count;
-    commands.reserve(count);
-    while (--count >= 0) {
-        pool.stream() >> cmdType;
-        AbstractCommand *cmd = AbstractCommand::createByType(static_cast<AbstractCommand::CommandType>(cmdType));
-        cmd->load(pool.stream());
-        commands += cmd;
-    }
+    commands = loadCommandList(pool.stream());
 }
 
 static void storePropertyList(PersistentPool &pool, const PropertyList &list)
@@ -263,11 +259,7 @@ void Transformer::store(PersistentPool &pool) const
             pool.stream() << p.value; // kind is always PropertyInModule
         }
     }
-    pool.stream() << commands.count();
-    foreach (AbstractCommand *cmd, commands) {
-        pool.stream() << int(cmd->type());
-        cmd->store(pool.stream());
-    }
+    storeCommandList(commands, pool.stream());
 }
 
 } // namespace Internal
diff --git a/src/lib/corelib/buildgraph/transformer.h b/src/lib/corelib/buildgraph/transformer.h
index 3ef30cc29..ee9ee4002 100644
--- a/src/lib/corelib/buildgraph/transformer.h
+++ b/src/lib/corelib/buildgraph/transformer.h
@@ -56,7 +56,7 @@ public:
     ArtifactSet inputs; // Subset of "children of all outputs".
     ArtifactSet outputs;
     RuleConstPtr rule;
-    QList<AbstractCommand *> commands;
+    QList<AbstractCommandPtr> commands;
     PropertyList propertiesRequestedInPrepareScript;
     PropertyList propertiesRequestedInCommands;
     QHash<QString, PropertyList> propertiesRequestedFromArtifactInPrepareScript;
@@ -69,7 +69,9 @@ public:
                                            const QString &defaultModuleName);
 
     ResolvedProductPtr product() const;
-    void setupInputs(QScriptEngine *scriptEngine, QScriptValue targetScriptValue);
+    static void setupInputs(QScriptValue targetScriptValue, const ArtifactSet &inputs,
+            const QString &defaultModuleName);
+    void setupInputs(QScriptValue targetScriptValue);
     void setupOutputs(QScriptEngine *scriptEngine, QScriptValue targetScriptValue);
     void createCommands(const ScriptFunctionConstPtr &script,
                         const RulesEvaluationContextPtr &evalContext, const QScriptValueList &args);
diff --git a/src/lib/corelib/buildgraph/tst_buildgraph.cpp b/src/lib/corelib/buildgraph/tst_buildgraph.cpp
index a159c2938..4f2aa3ebf 100644
--- a/src/lib/corelib/buildgraph/tst_buildgraph.cpp
+++ b/src/lib/corelib/buildgraph/tst_buildgraph.cpp
@@ -73,7 +73,7 @@ ResolvedProductConstPtr TestBuildGraph::productWithDirectCycle()
     child->children.insert(root);
     const ResolvedProductPtr product = ResolvedProduct::create();
     product->buildData.reset(new ProductBuildData);
-    product->buildData->targetArtifacts.insert(root);
+    product->buildData->roots.insert(root);
     return product;
 }
 
@@ -88,7 +88,7 @@ ResolvedProductConstPtr TestBuildGraph::productWithLessDirectCycle()
     grandchild->children.insert(root);
     const ResolvedProductPtr product = ResolvedProduct::create();
     product->buildData.reset(new ProductBuildData);
-    product->buildData->targetArtifacts << root;
+    product->buildData->roots << root;
     return product;
 }
 
@@ -101,7 +101,7 @@ ResolvedProductConstPtr TestBuildGraph::productWithNoCycle()
     root2->children.insert(root);
     const ResolvedProductPtr product = ResolvedProduct::create();
     product->buildData.reset(new ProductBuildData);
-    product->buildData->targetArtifacts << root << root2;
+    product->buildData->roots << root << root2;
     return product;
 }
 
diff --git a/src/lib/corelib/corelib.qbs b/src/lib/corelib/corelib.qbs
index 6ebda9b2c..c2e84ca81 100644
--- a/src/lib/corelib/corelib.qbs
+++ b/src/lib/corelib/corelib.qbs
@@ -73,12 +73,13 @@ QbsLibrary {
             "artifactset.h",
             "artifactvisitor.cpp",
             "artifactvisitor.h",
-            "automoc.cpp",
-            "automoc.h",
             "buildgraph.cpp",
             "buildgraph.h",
+            "buildgraphnode.cpp",
+            "buildgraphnode.h",
             "buildgraphloader.cpp",
             "buildgraphloader.h",
+            "buildgraphvisitor.h",
             "command.cpp",
             "command.h",
             "cycledetector.cpp",
@@ -93,6 +94,8 @@ QbsLibrary {
             "inputartifactscanner.h",
             "jscommandexecutor.cpp",
             "jscommandexecutor.h",
+            "nodeset.cpp",
+            "nodeset.h",
             "processcommandexecutor.cpp",
             "processcommandexecutor.h",
             "productbuilddata.cpp",
@@ -101,8 +104,14 @@ QbsLibrary {
             "productinstaller.h",
             "projectbuilddata.cpp",
             "projectbuilddata.h",
+            "qtmocscanner.cpp",
+            "qtmocscanner.h",
+            "rescuableartifactdata.cpp",
+            "rescuableartifactdata.h",
             "rulegraph.cpp",
             "rulegraph.h",
+            "rulenode.cpp",
+            "rulenode.h",
             "rulesapplicator.cpp",
             "rulesapplicator.h",
             "rulesevaluationcontext.cpp",
diff --git a/src/lib/corelib/language/builtindeclarations.cpp b/src/lib/corelib/language/builtindeclarations.cpp
index 54d221d96..5b2b09bf8 100644
--- a/src/lib/corelib/language/builtindeclarations.cpp
+++ b/src/lib/corelib/language/builtindeclarations.cpp
@@ -364,10 +364,19 @@ void BuiltinDeclarations::addRuleItem()
     PropertyDeclaration decl(QLatin1String("multiplex"), PropertyDeclaration::Boolean);
     decl.initialValueSource = QLatin1String("false");
     item << decl;
+    item << PropertyDeclaration(QLatin1String("name"), PropertyDeclaration::String);
     item << PropertyDeclaration(QLatin1String("inputs"), PropertyDeclaration::StringList);
+    item << PropertyDeclaration(QLatin1String("outputFileTags"), PropertyDeclaration::StringList);
+    decl = PropertyDeclaration(QLatin1String("outputArtifacts"), PropertyDeclaration::Verbatim);
+    decl.functionArgumentNames
+            << QLatin1String("project") << QLatin1String("product")
+            << QLatin1String("inputs") << QLatin1String("input");
+    item << decl;
     item << PropertyDeclaration(QLatin1String("usings"), PropertyDeclaration::StringList);
     item << PropertyDeclaration(QLatin1String("auxiliaryInputs"),
                                       PropertyDeclaration::StringList);
+    item << PropertyDeclaration(QLatin1String("excludedAuxiliaryInputs"),
+                                      PropertyDeclaration::StringList);
     item << PropertyDeclaration(QLatin1String("explicitlyDependsOn"),
                                       PropertyDeclaration::StringList);
     item << prepareScriptProperty();
diff --git a/src/lib/corelib/language/language.cpp b/src/lib/corelib/language/language.cpp
index 676551129..170d04863 100644
--- a/src/lib/corelib/language/language.cpp
+++ b/src/lib/corelib/language/language.cpp
@@ -35,6 +35,7 @@
 #include <buildgraph/productbuilddata.h>
 #include <buildgraph/projectbuilddata.h>
 #include <buildgraph/rulegraph.h> // TODO: Move to language?
+#include <buildgraph/transformer.h>
 #include <jsextensions/jsextensions.h>
 #include <logging/translator.h>
 #include <tools/hostosinfo.h>
@@ -290,6 +291,11 @@ bool operator==(const ResolvedFileContext &a, const ResolvedFileContext &b)
    * This is mostly needed for diagnostics.
    */
 
+bool ScriptFunction::isValid() const
+{
+    return location.isValid();
+}
+
 void ScriptFunction::load(PersistentPool &pool)
 {
     pool.stream()
@@ -354,12 +360,18 @@ static bool modulesAreEqual(const ResolvedModuleConstPtr &m1, const ResolvedModu
 
 QString Rule::toString() const
 {
-    QStringList outputTagsSorted = staticOutputFileTags().toStringList();
+    QStringList outputTagsSorted = collectedOutputFileTags().toStringList();
     outputTagsSorted.sort();
     QStringList inputTagsSorted = inputs.toStringList();
     inputTagsSorted.sort();
-    return QLatin1Char('[') + inputTagsSorted.join(QLatin1String(",")) + QLatin1String(" -> ")
-            + outputTagsSorted.join(QLatin1String(",")) + QLatin1Char(']');
+    return QLatin1Char('[') + outputTagsSorted.join(QLatin1String(","))
+            + QLatin1String("][")
+            + inputTagsSorted.join(QLatin1String(",")) + QLatin1Char(']');
+}
+
+bool Rule::acceptsAsInput(Artifact *artifact) const
+{
+    return artifact->fileTags.matches(inputs);
 }
 
 FileTags Rule::staticOutputFileTags() const
@@ -370,13 +382,27 @@ FileTags Rule::staticOutputFileTags() const
     return result;
 }
 
+FileTags Rule::collectedOutputFileTags() const
+{
+    return outputFileTags.isEmpty() ? staticOutputFileTags() : outputFileTags;
+}
+
+bool Rule::isDynamic() const
+{
+    return outputArtifactsScript->isValid();
+}
+
 void Rule::load(PersistentPool &pool)
 {
+    name = pool.idLoadString();
     prepareScript = pool.idLoadS<ScriptFunction>();
+    outputArtifactsScript = pool.idLoadS<ScriptFunction>();
     module = pool.idLoadS<ResolvedModule>();
     pool.stream()
         >> inputs
+        >> outputFileTags
         >> auxiliaryInputs
+        >> excludedAuxiliaryInputs
         >> usings
         >> explicitlyDependsOn
         >> multiplex;
@@ -386,11 +412,15 @@ void Rule::load(PersistentPool &pool)
 
 void Rule::store(PersistentPool &pool) const
 {
+    pool.storeString(name);
     pool.store(prepareScript);
+    pool.store(outputArtifactsScript);
     pool.store(module);
     pool.stream()
         << inputs
+        << outputFileTags
         << auxiliaryInputs
+        << excludedAuxiliaryInputs
         << usings
         << explicitlyDependsOn
         << multiplex;
@@ -407,6 +437,14 @@ ResolvedProduct::~ResolvedProduct()
 {
 }
 
+void ResolvedProduct::accept(BuildGraphVisitor *visitor) const
+{
+    if (!buildData)
+        return;
+    foreach (BuildGraphNode * const node, buildData->roots)
+        node->accept(visitor);
+}
+
 /*!
  * \brief Returns all files of all groups as source artifacts.
  * This includes the expanded list of wildcards.
@@ -661,19 +699,100 @@ void ResolvedProduct::setupRunEnvironment(ScriptEngine *engine, const QProcessEn
                                            topLevelProject(), env);
 }
 
-const QList<RuleConstPtr> &ResolvedProduct::topSortedRules() const
+void ResolvedProduct::registerAddedFileTag(const FileTag &fileTag, Artifact *artifact)
+{
+    QBS_CHECK(buildData);
+    QBS_CHECK(artifact->product == this);
+    if (buildData->removedArtifactsByFileTag.value(fileTag).contains(artifact)) {
+        buildData->removedArtifactsByFileTag[fileTag].remove(artifact);
+        return;
+    }
+    buildData->addedArtifactsByFileTag[fileTag].insert(artifact);
+}
+
+void ResolvedProduct::registerAddedArtifact(Artifact *artifact)
+{
+    QBS_CHECK(buildData);
+    QBS_CHECK(artifact->product == this);
+    foreach (const FileTag &tag, artifact->fileTags)
+        registerAddedFileTag(tag, artifact);
+}
+
+void ResolvedProduct::unregisterAddedArtifact(Artifact *artifact)
+{
+    ProductBuildData::ArtifactSetByFileTag::Iterator it
+            = buildData->addedArtifactsByFileTag.begin();
+    while (it != buildData->addedArtifactsByFileTag.end()) {
+        ArtifactSet &artifacts = it.value();
+        artifacts.remove(artifact);
+        if (artifacts.isEmpty())
+            it = buildData->addedArtifactsByFileTag.erase(it);
+        else
+            ++it;
+    }
+}
+
+void ResolvedProduct::registerRemovedFileTag(const FileTag &fileTag, Artifact *artifact)
 {
     QBS_CHECK(buildData);
-    if (buildData->topSortedRules.isEmpty()) {
-        RuleGraph ruleGraph;
-        ruleGraph.build(rules, fileTags);
-//        ruleGraph.dump();
-        buildData->topSortedRules = ruleGraph.topSorted();
-//        int i=0;
-//        foreach (RulePtr r, m_topSortedRules)
-//            qDebug() << ++i << r->toString() << (void*)r.data();
+    QBS_CHECK(artifact->product == this);
+    if (buildData->addedArtifactsByFileTag.value(fileTag).contains(artifact)) {
+        buildData->addedArtifactsByFileTag[fileTag].remove(artifact);
+        return;
+    }
+    buildData->removedArtifactsByFileTag[fileTag].insert(artifact);
+}
+
+void ResolvedProduct::registerArtifactWithChangedInputs(Artifact *artifact)
+{
+    QBS_CHECK(buildData);
+    QBS_CHECK(artifact->product == this);
+    QBS_CHECK(artifact->transformer);
+    if (artifact->transformer->rule->multiplex) {
+        // Reapplication of rules only makes sense for multiplex rules (e.g. linker).
+        buildData->artifactsWithChangedInputsPerRule[artifact->transformer->rule] += artifact;
+    }
+}
+
+void ResolvedProduct::unregisterArtifactWithChangedInputs(Artifact *artifact)
+{
+    QBS_CHECK(buildData);
+    QBS_CHECK(artifact->product == this);
+    QBS_CHECK(artifact->transformer);
+    buildData->artifactsWithChangedInputsPerRule[artifact->transformer->rule] -= artifact;
+}
+
+void ResolvedProduct::unmarkForReapplication(const RuleConstPtr &rule)
+{
+    QBS_CHECK(buildData);
+    buildData->artifactsWithChangedInputsPerRule.remove(rule);
+}
+
+const ArtifactSet ResolvedProduct::addedArtifactsByFileTag(const FileTag &tag) const
+{
+    return buildData->addedArtifactsByFileTag.value(tag);
+}
+
+const ArtifactSet ResolvedProduct::removedArtifactsByFileTag(const FileTag &tag) const
+{
+    return buildData->removedArtifactsByFileTag.value(tag);
+}
+
+bool ResolvedProduct::isMarkedForReapplication(const RuleConstPtr &rule) const
+{
+    return !buildData->artifactsWithChangedInputsPerRule.value(rule).isEmpty();
+}
+
+ArtifactSet ResolvedProduct::lookupArtifactsByFileTag(const FileTag &tag) const
+{
+    QBS_CHECK(buildData);
+    // ### slow. improve.
+    ArtifactSet result;
+    foreach (Artifact * const a, ArtifactSet::fromNodeSet(buildData->nodes)) {
+        if (a->fileTags.contains(tag))
+            result += a;
     }
-    return buildData->topSortedRules;
+    return result;
 }
 
 TopLevelProject *ResolvedProduct::topLevelProject() const
@@ -684,13 +803,13 @@ TopLevelProject *ResolvedProduct::topLevelProject() const
 static QStringList findGeneratedFiles(const Artifact *base, const FileTags &tags)
 {
     QStringList result;
-    foreach (const Artifact *parent, base->parents) {
+    foreach (const Artifact *parent, base->parentArtifacts()) {
         if (tags.isEmpty() || parent->fileTags.matches(tags))
             result << parent->filePath();
     }
 
     if (result.isEmpty() || tags.isEmpty())
-        foreach (const Artifact *parent, base->parents)
+        foreach (const Artifact *parent, base->parentArtifacts())
             result << findGeneratedFiles(parent, tags);
 
     return result;
@@ -702,7 +821,7 @@ QStringList ResolvedProduct::generatedFiles(const QString &baseFile, const FileT
     if (!data)
         return QStringList();
 
-    foreach (const Artifact *art, data->artifacts) {
+    foreach (const Artifact *art, ArtifactSet::fromNodeSet(data->nodes)) {
         if (art->filePath() == baseFile)
             return findGeneratedFiles(art, tags);
     }
@@ -713,6 +832,14 @@ ResolvedProject::ResolvedProject() : enabled(true), m_topLevelProject(0)
 {
 }
 
+void ResolvedProject::accept(BuildGraphVisitor *visitor) const
+{
+    foreach (const ResolvedProductPtr &product, products)
+        product->accept(visitor);
+    foreach (const ResolvedProjectPtr &subProject, subProjects)
+        subProject->accept(visitor);
+}
+
 TopLevelProject *ResolvedProject::topLevelProject()
 {
     if (m_topLevelProject)
@@ -756,8 +883,13 @@ void ResolvedProject::load(PersistentPool &pool)
     for (; --count >= 0;) {
         ResolvedProductPtr rProduct = pool.idLoadS<ResolvedProduct>();
         if (rProduct->buildData) {
-            foreach (Artifact * const a, rProduct->buildData->artifacts)
-                a->product = rProduct;
+            foreach (BuildGraphNode * const node, rProduct->buildData->nodes) {
+                node->product = rProduct;
+
+                // restore parent links
+                foreach (BuildGraphNode *child, node->children)
+                    child->parents.insert(node);
+            }
         }
         products.append(rProduct);
     }
@@ -1097,8 +1229,11 @@ bool operator==(const Rule &r1, const Rule &r2)
 
     return r1.module->name == r2.module->name
             && r1.prepareScript->sourceCode == r2.prepareScript->sourceCode
+            && r1.outputArtifactsScript->sourceCode == r2.outputArtifactsScript->sourceCode
             && r1.inputs == r2.inputs
+            && r1.outputFileTags == r2.outputFileTags
             && r1.auxiliaryInputs == r2.auxiliaryInputs
+            && r1.excludedAuxiliaryInputs == r2.excludedAuxiliaryInputs
             && r1.usings == r2.usings
             && r1.explicitlyDependsOn == r2.explicitlyDependsOn
             && r1.multiplex == r2.multiplex;
diff --git a/src/lib/corelib/language/language.h b/src/lib/corelib/language/language.h
index b62c0a1ab..c1e4f63fb 100644
--- a/src/lib/corelib/language/language.h
+++ b/src/lib/corelib/language/language.h
@@ -34,6 +34,7 @@
 #include "forward_decls.h"
 #include "jsimports.h"
 #include "propertymapinternal.h"
+#include <buildgraph/artifactset.h>
 #include <buildgraph/forward_decls.h>
 #include <tools/codelocation.h>
 #include <tools/fileinfo.h>
@@ -61,6 +62,7 @@ QT_END_NAMESPACE
 namespace qbs {
 namespace Internal {
 class BuildGraphLoader;
+class BuildGraphVisitor;
 
 class FileTagger : public PersistentObject
 {
@@ -235,6 +237,8 @@ public:
     ResolvedFileContextConstPtr fileContext;
     mutable QScriptValue scriptFunction;    // cache
 
+    bool isValid() const;
+
 private:
     ScriptFunction() {}
 
@@ -279,19 +283,26 @@ public:
     static RulePtr create() { return RulePtr(new Rule); }
 
     ResolvedModuleConstPtr module;
+    QString name;
     ScriptFunctionPtr prepareScript;
+    FileTags outputFileTags;                    // unused, if artifacts is non-empty
+    ScriptFunctionPtr outputArtifactsScript;    // unused, if artifacts is non-empty
     FileTags inputs;
     FileTags auxiliaryInputs;
+    FileTags excludedAuxiliaryInputs;
     FileTags usings;
     FileTags explicitlyDependsOn;
     bool multiplex;
-    QList<RuleArtifactPtr> artifacts;
+    QList<RuleArtifactPtr> artifacts;           // unused, if outputFileTags/outputArtifactsScript is non-empty
 
     // members that we don't need to save
     int ruleGraphId;
 
     QString toString() const;
+    bool acceptsAsInput(Artifact *artifact) const;
     FileTags staticOutputFileTags() const;
+    FileTags collectedOutputFileTags() const;
+    bool isDynamic() const;
 
 private:
     Rule() : multiplex(false), ruleGraphId(-1) {}
@@ -363,13 +374,25 @@ public:
     mutable QProcessEnvironment runEnvironment; // must not be saved
     QHash<QString, QString> executablePathCache;
 
+    void accept(BuildGraphVisitor *visitor) const;
     QList<SourceArtifactPtr> allFiles() const;
     QList<SourceArtifactPtr> allEnabledFiles() const;
     FileTags fileTagsForFileName(const QString &fileName) const;
     void setupBuildEnvironment(ScriptEngine *scriptEngine, const QProcessEnvironment &env) const;
     void setupRunEnvironment(ScriptEngine *scriptEngine, const QProcessEnvironment &env) const;
 
-    const QList<RuleConstPtr> &topSortedRules() const;
+    void registerAddedFileTag(const FileTag &fileTag, Artifact *artifact);
+    void registerAddedArtifact(Artifact *artifact);
+    void unregisterAddedArtifact(Artifact *artifact);
+    void registerRemovedFileTag(const FileTag &fileTag, Artifact *artifact);
+    void registerArtifactWithChangedInputs(Artifact *artifact);
+    void unregisterArtifactWithChangedInputs(Artifact *artifact);
+    void unmarkForReapplication(const RuleConstPtr &rule);
+    const ArtifactSet addedArtifactsByFileTag(const FileTag &tag) const;
+    const ArtifactSet removedArtifactsByFileTag(const FileTag &tag) const;
+    bool isMarkedForReapplication(const RuleConstPtr &rule) const;
+    ArtifactSet lookupArtifactsByFileTag(const FileTag &tag) const;
+
     TopLevelProject *topLevelProject() const;
 
     QStringList generatedFiles(const QString &baseFile, const FileTags &tags) const;
@@ -393,6 +416,8 @@ public:
     QList<ResolvedProjectPtr> subProjects;
     WeakPointer<ResolvedProject> parentProject;
 
+    void accept(BuildGraphVisitor *visitor) const;
+
     void setProjectProperties(const QVariantMap &config) { m_projectProperties = config; }
     const QVariantMap &projectProperties() const { return m_projectProperties; }
 
diff --git a/src/lib/corelib/language/projectresolver.cpp b/src/lib/corelib/language/projectresolver.cpp
index a5d952efd..4dcec436d 100644
--- a/src/lib/corelib/language/projectresolver.cpp
+++ b/src/lib/corelib/language/projectresolver.cpp
@@ -576,26 +576,44 @@ void ProjectResolver::resolveRule(Item *item, ProjectContext *projectContext)
     RulePtr rule = Rule::create();
 
     // read artifacts
+    bool hasArtifactChildren = false;
     bool hasAlwaysUpdatedArtifact = false;
     foreach (Item *child, item->children()) {
         if (Q_UNLIKELY(child->typeName() != QLatin1String("Artifact")))
             throw ErrorInfo(Tr::tr("'Rule' can only have children of type 'Artifact'."),
                                child->location());
 
+        hasArtifactChildren = true;
         resolveRuleArtifact(rule, child, &hasAlwaysUpdatedArtifact);
     }
 
-    if (Q_UNLIKELY(!hasAlwaysUpdatedArtifact))
+    if (Q_UNLIKELY(hasArtifactChildren && !hasAlwaysUpdatedArtifact))
         throw ErrorInfo(Tr::tr("At least one output artifact of a rule "
                            "must have alwaysUpdated set to true."),
                     item->location());
 
+    rule->name = m_evaluator->stringValue(item, QLatin1String("name"));
     rule->prepareScript = scriptFunctionValue(item, QLatin1String("prepare"));
+    rule->outputArtifactsScript = scriptFunctionValue(item, QLatin1String("outputArtifacts"));
+    if (rule->outputArtifactsScript->isValid()) {
+        if (hasArtifactChildren)
+            throw ErrorInfo(Tr::tr("The Rule.outputArtifacts script is not allowed in rules "
+                                   "that contain Artifact items."),
+                        item->location());
+        rule->outputFileTags = m_evaluator->fileTagsValue(item, "outputFileTags");
+        if (rule->outputFileTags.isEmpty())
+            throw ErrorInfo(Tr::tr("Rule.outputFileTags must be specified if "
+                                   "Rule.outputArtifacts is specified."),
+                            item->location());
+    }
+
     rule->multiplex = m_evaluator->boolValue(item, QLatin1String("multiplex"));
     rule->inputs = m_evaluator->fileTagsValue(item, QLatin1String("inputs"));
     rule->usings = m_evaluator->fileTagsValue(item, QLatin1String("usings"));
     rule->auxiliaryInputs
             = m_evaluator->fileTagsValue(item, QLatin1String("auxiliaryInputs"));
+    rule->excludedAuxiliaryInputs
+            = m_evaluator->fileTagsValue(item, QLatin1String("excludedAuxiliaryInputs"));
     rule->explicitlyDependsOn
             = m_evaluator->fileTagsValue(item, QLatin1String("explicitlyDependsOn"));
     rule->module = m_moduleContext ? m_moduleContext->module : projectContext->dummyModule;
diff --git a/src/lib/corelib/tools/persistence.cpp b/src/lib/corelib/tools/persistence.cpp
index f9906ed01..cc751f889 100644
--- a/src/lib/corelib/tools/persistence.cpp
+++ b/src/lib/corelib/tools/persistence.cpp
@@ -40,7 +40,7 @@
 namespace qbs {
 namespace Internal {
 
-static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-61";
+static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-62";
 
 PersistentPool::PersistentPool(const Logger &logger) : m_logger(logger)
 {
diff --git a/src/lib/qtprofilesetup/templates/core.qbs b/src/lib/qtprofilesetup/templates/core.qbs
index 2b052d3d1..3199e0db5 100644
--- a/src/lib/qtprofilesetup/templates/core.qbs
+++ b/src/lib/qtprofilesetup/templates/core.qbs
@@ -203,50 +203,28 @@ Module {
     }
 
     Rule {
-        inputs: ["moc_cpp"]
-
-        Artifact {
-            fileName: ModUtils.moduleProperty(product, "generatedFilesDir")
-                      + '/' + input.completeBaseName + ".moc"
-            fileTags: ["hpp"]
-        }
-
-        prepare: {
-            var cmd = new Command(Moc.fullPath(product),
-                                  Moc.args(product, input, output.fileName));
-            cmd.description = 'moc ' + FileInfo.fileName(input.fileName);
-            cmd.highlight = 'codegen';
-            return cmd;
-        }
-    }
-
-    Rule {
-        inputs: ["moc_hpp"]
-
-        Artifact {
-            fileName: ModUtils.moduleProperty(product, "generatedFilesDir")
-                      + "/moc_" + input.completeBaseName + ".cpp"
-            fileTags: [ "cpp" ]
-        }
-
-        prepare: {
-            var cmd = new Command(Moc.fullPath(product),
-                                  Moc.args(product, input, output.fileName));
-            cmd.description = 'moc ' + FileInfo.fileName(input.fileName);
-            cmd.highlight = 'codegen';
-            return cmd;
-        }
-    }
-
-    Rule {
-        inputs: ["moc_hpp_inc"]
-
-        Artifact {
-            fileName: ModUtils.moduleProperty(product, "generatedFilesDir")
-                      + "/moc_" + input.completeBaseName + ".cpp"
-            fileTags: [ "hpp" ]
+        name: "QtCoreMocRule"
+        inputs: ["cpp", "hpp"]
+        auxiliaryInputs: ["qt_plugin_metadata"]
+        excludedAuxiliaryInputs: ["unmocable"]
+        outputFileTags: ["hpp", "cpp", "unmocable"]
+        outputArtifacts: {
+            var mocinfo = QtMocScanner.apply(input);
+            if (!mocinfo.hasQObjectMacro)
+                return [];
+            var artifact = { fileTags: ["unmocable"] };
+            if (input.fileTags.contains("hpp")) {
+                artifact.filePath = ModUtils.moduleProperty(product, "generatedFilesDir")
+                        + "/moc_" + input.completeBaseName + ".cpp";
+            } else {
+                artifact.filePath = ModUtils.moduleProperty(product, "generatedFilesDir")
+                          + '/' + input.completeBaseName + ".moc";
+            }
+            artifact.fileTags.push(mocinfo.mustCompile ? "cpp" : "hpp");
+            if (mocinfo.hasPluginMetaDataMacro)
+                artifact.explicitlyDependsOn = ["qt_plugin_metadata"];
+            return [artifact];
         }
-
         prepare: {
             var cmd = new Command(Moc.fullPath(product),
                                   Moc.args(product, input, output.fileName));
diff --git a/src/plugins/scanner/cpp/cppscanner.cpp b/src/plugins/scanner/cpp/cppscanner.cpp
index 2735aa378..4bee84dd3 100644
--- a/src/plugins/scanner/cpp/cppscanner.cpp
+++ b/src/plugins/scanner/cpp/cppscanner.cpp
@@ -257,7 +257,7 @@ static const char **additionalFileTags(void *opaq, int *size)
 {
     static const char *thMocCpp[] = { "moc_cpp" };
     static const char *thMocHpp[] = { "moc_hpp" };
-    static const char *thMocPluginHpp[] = { "moc_plugin_hpp" };
+    static const char *thMocPluginHpp[] = { "moc_hpp_plugin" };
 
     Opaq *opaque = static_cast<Opaq*>(opaq);
     if (opaque->hasQObjectMacro) {
diff --git a/tests/auto/api/tst_api.cpp b/tests/auto/api/tst_api.cpp
index 7536f4302..3ef5d7364 100644
--- a/tests/auto/api/tst_api.cpp
+++ b/tests/auto/api/tst_api.cpp
@@ -326,6 +326,15 @@ void TestApi::changeContent()
     QVERIFY2(!errorInfo.hasError(), qPrintable(errorInfo.toString()));
 }
 
+static qbs::ErrorInfo forceRuleEvaluation(const qbs::Project project)
+{
+    qbs::BuildOptions buildOptions;
+    buildOptions.setDryRun(true);
+    QScopedPointer<qbs::BuildJob> buildJob(project.buildAllProducts(buildOptions));
+    waitForFinished(buildJob.data());
+    return buildJob->error();
+}
+
 void TestApi::disabledInstallGroup()
 {
     qbs::SetupProjectParameters setupParams = defaultSetupParameters();
@@ -335,7 +344,11 @@ void TestApi::disabledInstallGroup()
                                                                         m_logSink, 0));
     waitForFinished(job.data());
     QVERIFY2(!job->error().hasError(), qPrintable(job->error().toString()));
-    qbs::Project project = job->project();
+    const qbs::Project project = job->project();
+
+    const qbs::ErrorInfo errorInfo = forceRuleEvaluation(project);
+    QVERIFY2(!errorInfo.hasError(), qPrintable(errorInfo.toString()));
+
     qbs::ProjectData projectData = project.projectData();
     QCOMPARE(projectData.allProducts().count(), 1);
     qbs::ProductData product = projectData.allProducts().first();
@@ -358,6 +371,10 @@ void TestApi::fileTagsFilterOverride()
     waitForFinished(job.data());
     QVERIFY2(!job->error().hasError(), qPrintable(job->error().toString()));
     qbs::Project project = job->project();
+
+    const qbs::ErrorInfo errorInfo = forceRuleEvaluation(project);
+    QVERIFY2(!errorInfo.hasError(), qPrintable(errorInfo.toString()));
+
     qbs::ProjectData projectData = project.projectData();
     QCOMPARE(projectData.allProducts().count(), 1);
     const qbs::ProductData product = projectData.allProducts().first();
@@ -378,6 +395,10 @@ void TestApi::installableFiles()
     waitForFinished(job.data());
     QVERIFY2(!job->error().hasError(), qPrintable(job->error().toString()));
     qbs::Project project = job->project();
+
+    const qbs::ErrorInfo errorInfo = forceRuleEvaluation(project);
+    QVERIFY2(!errorInfo.hasError(), qPrintable(errorInfo.toString()));
+
     qbs::ProjectData projectData = project.projectData();
     QCOMPARE(projectData.allProducts().count(), 1);
     qbs::ProductData product = projectData.allProducts().first();
diff --git a/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/main.cpp b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/main.cpp
new file mode 100644
index 000000000..940a7628d
--- /dev/null
+++ b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/main.cpp
@@ -0,0 +1,7 @@
+#include "object.h"
+
+int main()
+{
+    Object o;
+    o.f();
+}
diff --git a/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.cpp b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.cpp
new file mode 100644
index 000000000..aab24f6c0
--- /dev/null
+++ b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.cpp
@@ -0,0 +1,13 @@
+#include "object.h"
+
+#include <QObject>
+
+// class InternalClass : public QObject
+// {
+//    Q_OBJECT
+// };
+
+void Object::f() { }
+
+
+// #include "object.moc"
diff --git a/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.h b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.h
new file mode 100644
index 000000000..37070b494
--- /dev/null
+++ b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/object.h
@@ -0,0 +1,4 @@
+class Object {
+public:
+    void f();
+};
diff --git a/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/project.qbs b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/project.qbs
new file mode 100644
index 000000000..6c8db1913
--- /dev/null
+++ b/tests/auto/blackbox/testdata/add-qobject-macro-to-cpp-file/project.qbs
@@ -0,0 +1,7 @@
+import qbs
+
+CppApplication {
+    Depends { name: "Qt.core" }
+    files: ["main.cpp", "object.h", "object.cpp"]
+}
+
diff --git a/tests/auto/blackbox/testdata/added-file-persistent/file.cpp b/tests/auto/blackbox/testdata/added-file-persistent/file.cpp
new file mode 100644
index 000000000..8101b05dc
--- /dev/null
+++ b/tests/auto/blackbox/testdata/added-file-persistent/file.cpp
@@ -0,0 +1 @@
+void f() { }
diff --git a/tests/auto/blackbox/testdata/added-file-persistent/main.cpp b/tests/auto/blackbox/testdata/added-file-persistent/main.cpp
new file mode 100644
index 000000000..1921f1feb
--- /dev/null
+++ b/tests/auto/blackbox/testdata/added-file-persistent/main.cpp
@@ -0,0 +1,3 @@
+void f();
+
+int main() { f(); }
diff --git a/tests/auto/blackbox/testdata/added-file-persistent/project.qbs b/tests/auto/blackbox/testdata/added-file-persistent/project.qbs
new file mode 100644
index 000000000..672886646
--- /dev/null
+++ b/tests/auto/blackbox/testdata/added-file-persistent/project.qbs
@@ -0,0 +1,8 @@
+import qbs
+
+CppApplication {
+    files: [
+        'main.cpp',
+        /* 'file.cpp' */
+    ]
+}
diff --git a/tests/auto/blackbox/testdata/fileTagger/moc_cpp.qbs b/tests/auto/blackbox/testdata/fileTagger/moc_cpp.qbs
index b56412bed..2bc02e23c 100644
--- a/tests/auto/blackbox/testdata/fileTagger/moc_cpp.qbs
+++ b/tests/auto/blackbox/testdata/fileTagger/moc_cpp.qbs
@@ -20,7 +20,7 @@ Project {
     Rule {
         inputs: ['text']
         Artifact {
-            fileTags: ['cpp', 'moc_cpp']
+            fileTags: ['cpp']
             fileName: input.baseName + '.cpp'
         }
         prepare: {
diff --git a/tests/auto/blackbox/tst_blackbox.cpp b/tests/auto/blackbox/tst_blackbox.cpp
index d92896223..105af71a8 100644
--- a/tests/auto/blackbox/tst_blackbox.cpp
+++ b/tests/auto/blackbox/tst_blackbox.cpp
@@ -199,6 +199,63 @@ void TestBlackbox::initTestCase()
     ccp(testSourceDir, testDataDir);
 }
 
+void TestBlackbox::addedFilePersistent()
+{
+    QDir::setCurrent(testDataDir + QLatin1String("/added-file-persistent"));
+
+    // On the initial run, linking will fail.
+    QbsRunParameters failedRunParams;
+    failedRunParams.expectFailure = true;
+    QVERIFY(runQbs(failedRunParams) != 0);
+
+    // Add a file. qbs must schedule it for rule application on the next build.
+    QFile projectFile("project.qbs");
+    QVERIFY2(projectFile.open(QIODevice::ReadWrite), qPrintable(projectFile.errorString()));
+    const QByteArray originalContent = projectFile.readAll();
+    QByteArray addedFileContent = originalContent;
+    addedFileContent.replace("/* 'file.cpp' */", "'file.cpp'");
+    projectFile.resize(0);
+    projectFile.write(addedFileContent);
+    waitForNewTimestamp();
+    projectFile.flush();
+    QCOMPARE(runQbs(QbsRunParameters("resolve")), 0);
+
+    // Remove the file again. qbs must unschedule the rule application again.
+    // Consequently, the linking step must fail as in the initial run.
+    projectFile.resize(0);
+    projectFile.write(originalContent);
+    waitForNewTimestamp();
+    projectFile.flush();
+    QVERIFY(runQbs(failedRunParams) != 0);
+
+    // Add the file again. qbs must schedule it for rule application on the next build.
+    projectFile.resize(0);
+    projectFile.write(addedFileContent);
+    waitForNewTimestamp();
+    projectFile.close();
+    QCOMPARE(runQbs(QbsRunParameters("resolve")), 0);
+
+    // qbs must remember that a file was scheduled for rule application. The build must then
+    // succeed, as now all necessary symbols are linked in.
+    QCOMPARE(runQbs(), 0);
+}
+
+void TestBlackbox::addQObjectMacroToCppFile()
+{
+    QDir::setCurrent(testDataDir + QLatin1String("/add-qobject-macro-to-cpp-file"));
+    QCOMPARE(runQbs(), 0);
+
+    waitForNewTimestamp();
+    QFile cppFile("object.cpp");
+    QVERIFY2(cppFile.open(QIODevice::ReadWrite), qPrintable(cppFile.errorString()));
+    QByteArray contents = cppFile.readAll();
+    contents.replace("// ", "");
+    cppFile.resize(0);
+    cppFile.write(contents);
+    cppFile.close();
+    QCOMPARE(runQbs(), 0);
+}
+
 void TestBlackbox::baseProperties()
 {
     QDir::setCurrent(testDataDir + QLatin1String("/baseProperties"));
@@ -1331,22 +1388,6 @@ void TestBlackbox::propertyChanges()
     QVERIFY(!m_qbsStdout.contains("compiling lib.cpp"));
     QVERIFY(!m_qbsStdout.contains("generated.txt"));
     QVERIFY(m_qbsStdout.contains("Making output from input"));
-
-    // Incremental build, irrelevant file tag of a rule in a module changed.
-    waitForNewTimestamp();
-    QVERIFY(moduleFile.open(QIODevice::ReadWrite));
-    contents = moduleFile.readAll();
-    contents.replace("inputs: ['test-input']", "inputs: ['test-input', 'hupe']");
-    moduleFile.resize(0);
-    moduleFile.write(contents);
-    moduleFile.close();
-    QCOMPARE(runQbs(params), 0);
-    QVERIFY(!m_qbsStdout.contains("compiling source1.cpp"));
-    QVERIFY(!m_qbsStdout.contains("compiling source2.cpp"));
-    QVERIFY(!m_qbsStdout.contains("compiling source3.cpp"));
-    QVERIFY(!m_qbsStdout.contains("compiling lib.cpp"));
-    QVERIFY(!m_qbsStdout.contains("generated.txt"));
-    QVERIFY(!m_qbsStdout.contains("Making output from input"));
 }
 
 void TestBlackbox::disabledProduct()
@@ -1388,7 +1429,6 @@ void TestBlackbox::dynamicLibs()
 
 void TestBlackbox::dynamicRuleOutputs()
 {
-    SKIP_TEST("QBS-370");
     const QString testDir = testDataDir + "/dynamicRuleOutputs";
     QDir::setCurrent(testDir);
     if (QFile::exists("work"))
@@ -1585,6 +1625,30 @@ void TestBlackbox::inheritQbsSearchPaths()
     QCOMPARE(runQbs(), 0);
 }
 
+void TestBlackbox::mocCppIncluded()
+{
+    QDir::setCurrent(testDataDir + "/moc_hpp_included");
+    QCOMPARE(runQbs(), 0); // Initial build.
+
+    // Touch header and try again.
+    waitForNewTimestamp();
+    QFile headerFile("object.h");
+    QVERIFY2(headerFile.open(QIODevice::WriteOnly | QIODevice::Append),
+             qPrintable(headerFile.errorString()));
+    headerFile.write("\n");
+    headerFile.close();
+    QCOMPARE(runQbs(), 0);
+
+    // Touch cpp file and try again.
+    waitForNewTimestamp();
+    QFile cppFile("object.cpp");
+    QVERIFY2(cppFile.open(QIODevice::WriteOnly | QIODevice::Append),
+             qPrintable(cppFile.errorString()));
+    cppFile.write("\n");
+    cppFile.close();
+    QCOMPARE(runQbs(), 0);
+}
+
 void TestBlackbox::objC()
 {
     QDir::setCurrent(testDataDir + "/objc");
diff --git a/tests/auto/blackbox/tst_blackbox.h b/tests/auto/blackbox/tst_blackbox.h
index 0c516d497..b29b86c52 100644
--- a/tests/auto/blackbox/tst_blackbox.h
+++ b/tests/auto/blackbox/tst_blackbox.h
@@ -96,6 +96,8 @@ public slots:
     void initTestCase();
 
 private slots:
+    void addedFilePersistent();
+    void addQObjectMacroToCppFile();
     void baseProperties();
     void build_project_data();
     void build_project();
@@ -117,6 +119,7 @@ private slots:
     void jsExtensionsPropertyList();
     void jsExtensionsTextFile();
     void inheritQbsSearchPaths();
+    void mocCppIncluded();
     void objC();
     void properQuoting();
     void propertiesBlocks();