introduce ability to build projects for the host system

when qmake runs into the new option(host_build) command, it will restart
the project evaluation with a host spec.

the new default host spec is called default-host (gasp!). it is
overridden with the pre-exising -spec / -platform option, while the new
-xspec / -xplatform option overrides the pre-existing default spec.
specifying -spec but not -xspec will set the xspec, too, so the behavior
is backwards-compatible. same for the XQMAKESPEC override read from
.qmake.cache and the environment variable.
the cleaner solution would be adding -hostspec, to be symmetrical with
the override semantics, but that would deviate from configure in turn.

Change-Id: I4297c873780af16ab7928421b434ce0f1d3820da
Reviewed-by: Joerg Bornemann <joerg.bornemann@nokia.com>

10 files changed, 128 insertions, 55 deletions

diff --git a/configure b/configure
index 1bb7bb9bf6..a4180bccc4 100755
--- a/configure
+++ b/configure
@@ -3491,8 +3491,9 @@ if true; then ###[ '!' -f "$outpath/bin/qmake" ];
     mv -f "$QMAKE_QCONFIG_H" "$QCONFIG_H"
 
     #mkspecs/default is used as a (gasp!) default mkspec so QMAKESPEC needn't be set once configured
-    rm -rf mkspecs/default
+    rm -rf mkspecs/default mkspecs/default-host
     ln -s `echo $XQMAKESPEC | sed "s,^${relpath}/mkspecs/,,"` mkspecs/default
+    ln -s `echo $QMAKESPEC | sed "s,^${relpath}/mkspecs/,,"` mkspecs/default-host
     mkdir -p "$outpath/qmake" || exit
     # fix makefiles
     for mkfile in GNUmakefile Makefile; do
@@ -5906,9 +5907,14 @@ EOF
 
 #dump the qmake spec
 if [ -d "$outpath/mkspecs/$XPLATFORM" ]; then
-   echo "QMAKESPEC = \$\$QT_BUILD_TREE/mkspecs/$XPLATFORM" >> "$CACHEFILE.tmp"
+   echo "XQMAKESPEC = \$\$QT_BUILD_TREE/mkspecs/$XPLATFORM" >> "$CACHEFILE.tmp"
 else
-   echo "QMAKESPEC = $XPLATFORM" >> "$CACHEFILE.tmp"
+   echo "XQMAKESPEC = $XPLATFORM" >> "$CACHEFILE.tmp"
+fi
+if [ -d "$outpath/mkspecs/$PLATFORM" ]; then
+   echo "QMAKESPEC = \$\$QT_BUILD_TREE/mkspecs/$PLATFORM" >> "$CACHEFILE.tmp"
+else
+   echo "QMAKESPEC = $PLATFORM" >> "$CACHEFILE.tmp"
 fi
 
 # replace .qmake.cache if it differs from the newly created temp file
diff --git a/qmake/generators/makefile.cpp b/qmake/generators/makefile.cpp
index d37089ee35..97370f06d7 100644
--- a/qmake/generators/makefile.cpp
+++ b/qmake/generators/makefile.cpp
@@ -2193,7 +2193,9 @@ QString MakefileGenerator::buildArgs(const QString &outdir)
     if(!Option::mkfile::do_dep_heuristics)
         ret += " -nodependheuristics";
     if(!Option::mkfile::qmakespec_commandline.isEmpty())
-        ret += " -spec " + specdir(outdir);
+        ret += " -spec " + specdir(outdir, 1);
+    if (!Option::mkfile::xqmakespec_commandline.isEmpty())
+        ret += " -xspec " + specdir(outdir, 0);
     if (Option::target_mode_overridden) {
         if (Option::target_mode == Option::TARG_MACX_MODE)
             ret += " -macx";
@@ -3046,13 +3048,14 @@ QStringList
 }
 
 QString
-MakefileGenerator::specdir(const QString &outdir)
+MakefileGenerator::specdir(const QString &outdir, int host_build)
 {
 #if 0
     if(!spec.isEmpty())
         return spec;
 #endif
-    spec = fileFixify(Option::mkfile::qmakespec, outdir);
+    spec = fileFixify((host_build >= 0 ? bool(host_build) : project->isHostBuild())
+                      ? Option::mkfile::qmakespec : Option::mkfile::xqmakespec, outdir);
     return spec;
 }
 
diff --git a/qmake/generators/makefile.h b/qmake/generators/makefile.h
index 5b64ea68fb..a4ec259bb0 100644
--- a/qmake/generators/makefile.h
+++ b/qmake/generators/makefile.h
@@ -187,7 +187,7 @@ protected:
 
     //subclasses can use these to query information about how the generator was "run"
     QString buildArgs(const QString &outdir=QString());
-    QString specdir(const QString &outdir=QString());
+    QString specdir(const QString &outdir = QString(), int host_build = -1);
 
     virtual QStringList &findDependencies(const QString &file);
     virtual bool doDepends() const { return Option::mkfile::do_deps; }
diff --git a/qmake/generators/win32/msvc_vcproj.cpp b/qmake/generators/win32/msvc_vcproj.cpp
index 951784ec28..cd45ea6cee 100644
--- a/qmake/generators/win32/msvc_vcproj.cpp
+++ b/qmake/generators/win32/msvc_vcproj.cpp
@@ -649,12 +649,15 @@ nextfile:
     t << _slnProjConfBeg;
     for(QList<VcsolutionDepend*>::Iterator it = solution_cleanup.begin(); it != solution_cleanup.end(); ++it) {
         QString platform = is64Bit ? "x64" : "Win32";
+        QString xplatform = platform;
         if (!project->isEmpty("CE_SDK") && !project->isEmpty("CE_ARCH"))
-            platform = project->values("CE_SDK").join(" ") + " (" + project->first("CE_ARCH") + ")";
-        t << "\n\t\t" << (*it)->uuid << QString(_slnProjDbgConfTag1).arg(platform) << platform;
-        t << "\n\t\t" << (*it)->uuid << QString(_slnProjDbgConfTag2).arg(platform) << platform;
-        t << "\n\t\t" << (*it)->uuid << QString(_slnProjRelConfTag1).arg(platform) << platform;
-        t << "\n\t\t" << (*it)->uuid << QString(_slnProjRelConfTag2).arg(platform) << platform;
+            xplatform = project->values("CE_SDK").join(" ") + " (" + project->first("CE_ARCH") + ")";
+        if (!project->isHostBuild())
+            platform = xplatform;
+        t << "\n\t\t" << (*it)->uuid << QString(_slnProjDbgConfTag1).arg(xplatform) << platform;
+        t << "\n\t\t" << (*it)->uuid << QString(_slnProjDbgConfTag2).arg(xplatform) << platform;
+        t << "\n\t\t" << (*it)->uuid << QString(_slnProjRelConfTag1).arg(xplatform) << platform;
+        t << "\n\t\t" << (*it)->uuid << QString(_slnProjRelConfTag2).arg(xplatform) << platform;
     }
     t << _slnProjConfEnd;
     t << _slnExtSections;
@@ -858,7 +861,7 @@ void VcprojGenerator::initProject()
     }
 
     vcProject.Keyword = project->first("VCPROJ_KEYWORD");
-    if (project->isEmpty("CE_SDK") || project->isEmpty("CE_ARCH")) {
+    if (project->isHostBuild() || project->isEmpty("CE_SDK") || project->isEmpty("CE_ARCH")) {
         vcProject.PlatformName = (is64Bit ? "x64" : "Win32");
     } else {
         vcProject.PlatformName = project->values("CE_SDK").join(" ") + " (" + project->first("CE_ARCH") + ")";
@@ -922,7 +925,7 @@ void VcprojGenerator::initConfiguration()
     if (conf.Name.isEmpty())
         conf.Name = isDebug ? "Debug" : "Release";
     conf.ConfigurationName = conf.Name;
-    if (project->isEmpty("CE_SDK") || project->isEmpty("CE_ARCH")) {
+    if (project->isHostBuild() || project->isEmpty("CE_SDK") || project->isEmpty("CE_ARCH")) {
         conf.Name += (is64Bit ? "|x64" : "|Win32");
     } else {
         conf.Name += "|" + project->values("CE_SDK").join(" ") + " (" + project->first("CE_ARCH") + ")";
@@ -948,7 +951,7 @@ void VcprojGenerator::initConfiguration()
     initPreBuildEventTools();
     initPostBuildEventTools();
     // Only deploy for CE projects
-    if (!project->isEmpty("CE_SDK") && !project->isEmpty("CE_ARCH"))
+    if (!project->isHostBuild() && !project->isEmpty("CE_SDK") && !project->isEmpty("CE_ARCH"))
         initDeploymentTool();
     initPreLinkEventTools();
 
@@ -1084,7 +1087,7 @@ void VcprojGenerator::initPostBuildEventTools()
 
     QString signature = !project->isEmpty("SIGNATURE_FILE") ? var("SIGNATURE_FILE") : var("DEFAULT_SIGNATURE");
     bool useSignature = !signature.isEmpty() && !project->isActiveConfig("staticlib") &&
-                        !project->isEmpty("CE_SDK") && !project->isEmpty("CE_ARCH");
+                        !project->isHostBuild() && !project->isEmpty("CE_SDK") && !project->isEmpty("CE_ARCH");
     if (useSignature) {
         conf.postBuild.CommandLine.prepend(
                 QLatin1String("signtool sign /F ") + signature + QLatin1String(" \"$(TargetPath)\""));
@@ -1578,7 +1581,8 @@ QString VcprojGenerator::findTemplate(QString file)
 {
     QString ret;
     if(!exists((ret = file)) &&
-       !exists((ret = QString(Option::mkfile::qmakespec + "/" + file))) &&
+       !exists((ret = QString((project->isHostBuild()
+                               ? Option::mkfile::qmakespec : Option::mkfile::xqmakespec) + '/' + file))) &&
        !exists((ret = QString(QLibraryInfo::location(QLibraryInfo::HostDataPath) + "/win32-msvc.net/" + file))) &&
        !exists((ret = QString(QLibraryInfo::location(QLibraryInfo::HostDataPath) + "/win32-msvc2002/" + file))) &&
        !exists((ret = QString(QLibraryInfo::location(QLibraryInfo::HostDataPath) + "/win32-msvc2003/" + file))) &&
diff --git a/qmake/option.cpp b/qmake/option.cpp
index de907f0528..836cc3f492 100644
--- a/qmake/option.cpp
+++ b/qmake/option.cpp
@@ -107,6 +107,7 @@ QStringList Option::projfile::project_dirs;
 
 //QMAKE_GENERATE_MAKEFILE stuff
 QString Option::mkfile::qmakespec;
+QString Option::mkfile::xqmakespec;
 int Option::mkfile::cachefile_depth = -1;
 bool Option::mkfile::do_deps = true;
 bool Option::mkfile::do_mocs = true;
@@ -117,6 +118,7 @@ bool Option::mkfile::do_cache = true;
 QString Option::mkfile::cachefile;
 QStringList Option::mkfile::project_files;
 QString Option::mkfile::qmakespec_commandline;
+QString Option::mkfile::xqmakespec_commandline;
 
 static Option::QMAKE_MODE default_mode(QString progname)
 {
@@ -327,6 +329,9 @@ Option::parseCommandLine(int argc, char **argv, int skip)
                     } else if(opt == "platform" || opt == "spec") {
                         Option::mkfile::qmakespec = cleanSpec(argv[++x]);
                         Option::mkfile::qmakespec_commandline = argv[x];
+                    } else if (opt == "xplatform" || opt == "xspec") {
+                        Option::mkfile::xqmakespec = cleanSpec(argv[++x]);
+                        Option::mkfile::xqmakespec_commandline = argv[x];
                     } else {
                         fprintf(stderr, "***Unknown option -%s\n", opt.toLatin1().constData());
                         return Option::QMAKE_CMDLINE_SHOW_USAGE | Option::QMAKE_CMDLINE_ERROR;
@@ -381,6 +386,9 @@ Option::parseCommandLine(int argc, char **argv, int skip)
     if (!user_configs.isEmpty())
         Option::before_user_vars += "CONFIG += " + user_configs.join(" ");
 
+    if (Option::mkfile::xqmakespec.isEmpty())
+        Option::mkfile::xqmakespec = Option::mkfile::qmakespec;
+
     return Option::QMAKE_CMDLINE_SUCCESS;
 }
 
@@ -536,8 +544,13 @@ Option::init(int argc, char **argv)
     //last chance for defaults
     if(Option::qmake_mode == Option::QMAKE_GENERATE_MAKEFILE ||
         Option::qmake_mode == Option::QMAKE_GENERATE_PRL) {
-        if(Option::mkfile::qmakespec.isNull() || Option::mkfile::qmakespec.isEmpty())
+        if (Option::mkfile::xqmakespec.isEmpty())
+            Option::mkfile::xqmakespec = QString::fromLocal8Bit(qgetenv("XQMAKESPEC").constData());
+        if (Option::mkfile::qmakespec.isEmpty()) {
             Option::mkfile::qmakespec = QString::fromLocal8Bit(qgetenv("QMAKESPEC").constData());
+            if (Option::mkfile::xqmakespec.isEmpty())
+                Option::mkfile::xqmakespec = Option::mkfile::qmakespec;
+        }
 
         //try REALLY hard to do it for them, lazy..
         if(Option::mkfile::project_files.isEmpty()) {
diff --git a/qmake/option.h b/qmake/option.h
index 0ec6a36a29..f6f5dbbb9d 100644
--- a/qmake/option.h
+++ b/qmake/option.h
@@ -196,6 +196,7 @@ struct Option
     //QMAKE_GENERATE_MAKEFILE options
     struct mkfile {
         static QString qmakespec;
+        static QString xqmakespec;
         static bool do_cache;
         static bool do_deps;
         static bool do_mocs;
@@ -206,6 +207,7 @@ struct Option
         static int cachefile_depth;
         static QStringList project_files;
         static QString qmakespec_commandline;
+        static QString xqmakespec_commandline;
     };
 
 private:
diff --git a/qmake/project.cpp b/qmake/project.cpp
index 4d4dfe955e..f3a3856d82 100644
--- a/qmake/project.cpp
+++ b/qmake/project.cpp
@@ -531,7 +531,7 @@ static void qmake_error_msg(const QString &msg)
    1) features/(unix|win32|macx)/
    2) features/
 */
-QStringList qmake_feature_paths(QMakeProperty *prop=0)
+QStringList qmake_feature_paths(QMakeProperty *prop, bool host_build)
 {
     const QString mkspecs_concat = QLatin1String("/mkspecs");
     const QString base_concat = QLatin1String("/features");
@@ -578,12 +578,13 @@ QStringList qmake_feature_paths(QMakeProperty *prop=0)
                     feature_roots << ((*it) + mkspecs_concat + (*concat_it));
         }
     }
-    if(!Option::mkfile::qmakespec.isEmpty()) {
+    QString *specp = host_build ? &Option::mkfile::qmakespec : &Option::mkfile::xqmakespec;
+    if (!specp->isEmpty()) {
         // The spec is already platform-dependent, so no subdirs here.
-        feature_roots << Option::mkfile::qmakespec + base_concat;
+        feature_roots << *specp + base_concat;
 
         // Also check directly under the root directory of the mkspecs collection
-        QFileInfo specfi(Option::mkfile::qmakespec);
+        QFileInfo specfi(*specp);
         QDir specrootdir(specfi.absolutePath());
         while (!specrootdir.isRoot()) {
             const QString specrootpath = specrootdir.path();
@@ -629,16 +630,7 @@ QMakeProject::~QMakeProject()
 {
     if(own_prop)
         delete prop;
-    for(QHash<QString, FunctionBlock*>::iterator it = replaceFunctions.begin(); it != replaceFunctions.end(); ++it) {
-        if(!it.value()->deref())
-            delete it.value();
-    }
-    replaceFunctions.clear();
-    for(QHash<QString, FunctionBlock*>::iterator it = testFunctions.begin(); it != testFunctions.end(); ++it) {
-        if(!it.value()->deref())
-            delete it.value();
-    }
-    testFunctions.clear();
+    cleanup();
 }
 
 
@@ -653,14 +645,29 @@ QMakeProject::init(QMakeProperty *p)
         own_prop = false;
     }
     recursive = false;
+    host_build = false;
     reset();
 }
 
+void
+QMakeProject::cleanup()
+{
+    for (QHash<QString, FunctionBlock*>::iterator it = replaceFunctions.begin(); it != replaceFunctions.end(); ++it)
+        if (!it.value()->deref())
+            delete it.value();
+    replaceFunctions.clear();
+    for (QHash<QString, FunctionBlock*>::iterator it = testFunctions.begin(); it != testFunctions.end(); ++it)
+        if (!it.value()->deref())
+            delete it.value();
+    testFunctions.clear();
+}
+
 // Duplicate project. It is *not* allowed to call the complex read() functions on the copy.
 QMakeProject::QMakeProject(QMakeProject *p, const QHash<QString, QStringList> *_vars)
 {
     init(p->properties());
     vars = _vars ? *_vars : p->variables();
+    host_build = p->host_build;
     for(QHash<QString, FunctionBlock*>::iterator it = p->replaceFunctions.begin(); it != p->replaceFunctions.end(); ++it) {
         it.value()->ref();
         replaceFunctions.insert(it.key(), it.value());
@@ -680,6 +687,7 @@ QMakeProject::reset()
     iterator = 0;
     function = 0;
     backslashWarned = false;
+    need_restart = false;
 }
 
 bool
@@ -1226,6 +1234,8 @@ QMakeProject::read(QTextStream &file, QHash<QString, QStringList> &place)
                 }
                 s = "";
                 numLines = 0;
+                if (need_restart)
+                    break;
             }
         }
     }
@@ -1271,7 +1281,7 @@ QMakeProject::read(const QString &file, QHash<QString, QStringList> &place)
         if(!using_stdin)
             qfile.close();
     }
-    if(scope_blocks.count() != 1) {
+    if (!need_restart && scope_blocks.count() != 1) {
         qmake_error_msg("Unterminated conditional block at end of file");
         ret = false;
     }
@@ -1290,6 +1300,7 @@ QMakeProject::read(const QString &project, uchar cmd)
 bool
 QMakeProject::read(uchar cmd)
 {
+  again:
     if ((cmd & ReadSetup) && base_vars.isEmpty()) {
         // hack to get the Option stuff in there
         base_vars["QMAKE_EXT_CPP"] = Option::cpp_ext;
@@ -1320,8 +1331,13 @@ QMakeProject::read(uchar cmd)
                 Option::mkfile::cachefile.clear();
                 goto no_cache;
             }
-            if (Option::mkfile::qmakespec.isEmpty() && !cache["QMAKESPEC"].isEmpty())
+            if (Option::mkfile::xqmakespec.isEmpty() && !cache["XQMAKESPEC"].isEmpty())
+                Option::mkfile::xqmakespec = cache["XQMAKESPEC"].first();
+            if (Option::mkfile::qmakespec.isEmpty() && !cache["QMAKESPEC"].isEmpty()) {
                 Option::mkfile::qmakespec = cache["QMAKESPEC"].first();
+                if (Option::mkfile::xqmakespec.isEmpty())
+                    Option::mkfile::xqmakespec = Option::mkfile::qmakespec;
+            }
 
             if (Option::output_dir.startsWith(project_build_root))
                 Option::mkfile::cachefile_depth =
@@ -1355,9 +1371,10 @@ QMakeProject::read(uchar cmd)
         }
 
         {             // parse mkspec
-            QString qmakespec = Option::mkfile::qmakespec;
+            QString *specp = host_build ? &Option::mkfile::qmakespec : &Option::mkfile::xqmakespec;
+            QString qmakespec = *specp;
             if (qmakespec.isEmpty())
-                qmakespec = "default";
+                qmakespec = host_build ? "default-host" : "default";
             if (QDir::isRelativePath(qmakespec)) {
                     QStringList mkspec_roots = qmake_mkspec_paths();
                     debug_msg(2, "Looking for mkspec %s in (%s)", qmakespec.toLatin1().constData(),
@@ -1367,7 +1384,7 @@ QMakeProject::read(uchar cmd)
                         QString mkspec = (*it) + QLatin1Char('/') + qmakespec;
                         if (QFile::exists(mkspec)) {
                             found_mkspec = true;
-                            Option::mkfile::qmakespec = qmakespec = mkspec;
+                            *specp = qmakespec = mkspec;
                             break;
                         }
                     }
@@ -1441,6 +1458,11 @@ QMakeProject::read(uchar cmd)
             pfile += Option::pro_ext;
         if(!read(pfile, vars))
             return false;
+        if (need_restart) {
+            base_vars.clear();
+            cleanup();
+            goto again;
+        }
     }
 
     if (cmd & ReadSetup) {
@@ -1537,7 +1559,7 @@ QMakeProject::resolveSpec(QString *spec, const QString &qmakespec)
 {
     if (spec->isEmpty()) {
         *spec = QFileInfo(qmakespec).fileName();
-        if (*spec == "default") {
+        if (*spec == "default" || *spec == "default-host") {
 #ifdef Q_OS_UNIX
             char buffer[1024];
             int l = readlink(qmakespec.toLatin1().constData(), buffer, 1023);
@@ -1586,9 +1608,14 @@ QMakeProject::isActiveConfig(const QString &x, bool regex, QHash<QString, QStrin
         return Option::target_mode == Option::TARG_WIN_MODE;
     }
 
+    if (x == "host_build")
+        return host_build ? "true" : "false";
+
     //mkspecs
-    static QString spec;
-    resolveSpec(&spec, Option::mkfile::qmakespec);
+    static QString hspec, xspec;
+    resolveSpec(&hspec, Option::mkfile::qmakespec);
+    resolveSpec(&xspec, Option::mkfile::xqmakespec);
+    const QString &spec = host_build ? hspec : xspec;
     QRegExp re(x, Qt::CaseSensitive, QRegExp::Wildcard);
     if((regex && re.exactMatch(spec)) || (!regex && spec == x))
         return true;
@@ -1646,9 +1673,10 @@ QMakeProject::doProjectInclude(QString file, uchar flags, QHash<QString, QString
             file += Option::prf_ext;
         validateModes(); // init dir_sep
         if(file.indexOf(QLatin1Char('/')) == -1 || !QFile::exists(file)) {
-            static QStringList *feature_roots = 0;
+            static QStringList *all_feature_roots[2] = { 0, 0 };
+            QStringList *&feature_roots = all_feature_roots[host_build];
             if(!feature_roots) {
-                feature_roots = new QStringList(qmake_feature_paths(prop));
+                feature_roots = new QStringList(qmake_feature_paths(prop, host_build));
                 qmakeAddCacheClear(qmakeDeleteCacheClear<QStringList>, (void**)&feature_roots);
             }
             debug_msg(2, "Looking for feature '%s' in (%s)", file.toLatin1().constData(),
@@ -2742,6 +2770,11 @@ QMakeProject::doProjectTest(QString func, QList<QStringList> args_list, QHash<QS
         }
         if (args.first() == "recursive") {
             recursive = true;
+        } else if (args.first() == "host_build") {
+            if (!host_build && isActiveConfig("cross_compile")) {
+                host_build = true;
+                need_restart = true;
+            }
         } else {
             fprintf(stderr, "%s:%d: unrecognized option() argument '%s'.\n",
                     parser.file.toLatin1().constData(), parser.line_no,
diff --git a/qmake/project.h b/qmake/project.h
index ccdc1b63f1..700509b2a6 100644
--- a/qmake/project.h
+++ b/qmake/project.h
@@ -79,6 +79,8 @@ class QMakeProject
     QHash<QString, FunctionBlock*> testFunctions, replaceFunctions;
 
     bool recursive;
+    bool host_build;
+    bool need_restart;
     bool own_prop;
     bool backslashWarned;
     QString pfile;
@@ -107,6 +109,7 @@ class QMakeProject
     bool doVariableReplace(QString &str, QHash<QString, QStringList> &place);
     QStringList doVariableReplaceExpand(const QString &str, QHash<QString, QStringList> &place, bool *ok=0);
     void init(QMakeProperty *);
+    void cleanup();
     QStringList &values(const QString &v, QHash<QString, QStringList> &place);
     void validateModes();
     void resolveSpec(QString *spec, const QString &qmakespec);
@@ -160,6 +163,7 @@ public:
     QHash<QString, QStringList> &variables(); // No compat mapping and magic, obviously
 
     bool isRecursive() const { return recursive; }
+    bool isHostBuild() const { return host_build; }
 
 protected:
     friend class MakefileGenerator;
diff --git a/qtbase.pro b/qtbase.pro
index 5efe77e99d..e8a26b7e9f 100644
--- a/qtbase.pro
+++ b/qtbase.pro
@@ -118,15 +118,17 @@ INSTALLS += configtests
 mkspecs.path = $$[QT_HOST_DATA]/mkspecs
 mkspecs.files = $$OUT_PWD/mkspecs/qconfig.pri $$OUT_PWD/mkspecs/qmodule.pri $$OUT_PWD/mkspecs/qdevice.pri $$files($$PWD/mkspecs/*)
 mkspecs.files -= $$PWD/mkspecs/modules
-unix { 
-   DEFAULT_QMAKESPEC = $$QMAKESPEC
-   DEFAULT_QMAKESPEC ~= s,^.*mkspecs/,,g
-   mkspecs.commands += $(DEL_FILE) $(INSTALL_ROOT)$$mkspecs.path/default; $(SYMLINK) $$DEFAULT_QMAKESPEC $(INSTALL_ROOT)$$mkspecs.path/default
-   mkspecs.files -= $$PWD/mkspecs/default
-}
-win32:!equals(OUT_PWD, $$PWD) {
+unix {
+    DEFAULT_QMAKESPEC = $$replace(QMAKESPEC, ^.*mkspecs/, )
+    DEFAULT_XQMAKESPEC = $$replace(XQMAKESPEC, ^.*mkspecs/, )
+    mkspecs.commands = \
+        $(DEL_FILE) $(INSTALL_ROOT)$$mkspecs.path/default-host $(INSTALL_ROOT)$$mkspecs.path/default; \
+        $(SYMLINK) $$DEFAULT_QMAKESPEC $(INSTALL_ROOT)$$mkspecs.path/default-host && \
+        $(SYMLINK) $$DEFAULT_XQMAKESPEC $(INSTALL_ROOT)$$mkspecs.path/default
+    mkspecs.files -= $$PWD/mkspecs/default-host $$PWD/mkspecs/default
+} else:!equals(OUT_PWD, $$PWD) {
     # When shadow building on Windows, the default mkspec only exists in the build tree.
-    mkspecs.files += $$OUT_PWD/mkspecs/default
+    mkspecs.files += $$OUT_PWD/mkspecs/default-host $$OUT_PWD/mkspecs/default
 }
 INSTALLS += mkspecs
 
diff --git a/tools/configure/configureapp.cpp b/tools/configure/configureapp.cpp
index ba50d9604c..ff2744397d 100644
--- a/tools/configure/configureapp.cpp
+++ b/tools/configure/configureapp.cpp
@@ -2583,13 +2583,18 @@ void Configure::generateCachefile()
         moduleStream << "QMAKE_INCDIR_QT = $$QT_BUILD_TREE" << fixSeparators("/include", true) << endl;
         moduleStream << "QMAKE_LIBDIR_QT = $$QT_BUILD_TREE" << fixSeparators("/lib", true) << endl;
 
-
-        QString targetSpec = dictionary.contains("XQMAKESPEC") ? dictionary[ "XQMAKESPEC" ] : dictionary[ "QMAKESPEC" ];
-        QString mkspec_path = fixSeparators(sourcePath + "/mkspecs/" + targetSpec);
+        QString hostSpec = dictionary[ "QMAKESPEC" ];
+        QString targetSpec = dictionary.contains("XQMAKESPEC") ? dictionary[ "XQMAKESPEC" ] : hostSpec;
+        QString xmkspec_path = fixSeparators(sourcePath + "/mkspecs/" + targetSpec);
+        if (QFile::exists(xmkspec_path))
+            moduleStream << "XQMAKESPEC      = " << escapeSeparators(xmkspec_path) << endl;
+        else
+            moduleStream << "XQMAKESPEC      = " << fixSeparators(targetSpec, true) << endl;
+        QString mkspec_path = fixSeparators(sourcePath + "/mkspecs/" + hostSpec);
         if (QFile::exists(mkspec_path))
             moduleStream << "QMAKESPEC       = " << escapeSeparators(mkspec_path) << endl;
         else
-            moduleStream << "QMAKESPEC       = " << fixSeparators(targetSpec, true) << endl;
+            moduleStream << "QMAKESPEC       = " << fixSeparators(hostSpec, true) << endl;
 
         if (dictionary["QT_EDITION"] != "QT_EDITION_OPENSOURCE")
             moduleStream << "DEFINES        *= QT_EDITION=QT_EDITION_DESKTOP" << endl;
@@ -3109,7 +3114,8 @@ void Configure::generateConfigfiles()
     }
 
     QString spec = dictionary.contains("XQMAKESPEC") ? dictionary["XQMAKESPEC"] : dictionary["QMAKESPEC"];
-    if (!copySpec("default", "", spec))
+    if (!copySpec("default", "", spec)
+        || !copySpec("default-host", "host ", dictionary["QMAKESPEC"]))
         return;
 
     // Generate the new qconfig.cpp file