6 files changed, 13 insertions, 7 deletions
diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index ef8ffa8620..31b964897f 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -302,7 +302,6 @@ Document::Document(bool debugMode)
     , program(0)
     , indexOfRootObject(0)
     , jsGenerator(&jsModule)
-    , unitFlags(0)
 {
 }
 
@@ -1393,7 +1392,6 @@ QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output, QQmlEngine
 
     QV4::CompiledData::Unit *qmlUnit = reinterpret_cast<QV4::CompiledData::Unit *>(data);
     qmlUnit->unitSize = totalSize;
-    qmlUnit->flags |= output.unitFlags;
     qmlUnit->flags |= QV4::CompiledData::Unit::IsQml;
     qmlUnit->offsetToImports = unitSize;
     qmlUnit->nImports = output.imports.count();
diff --git a/src/qml/compiler/qqmlirbuilder_p.h b/src/qml/compiler/qqmlirbuilder_p.h
index eedc262e7a..cc16dc2104 100644
--- a/src/qml/compiler/qqmlirbuilder_p.h
+++ b/src/qml/compiler/qqmlirbuilder_p.h
@@ -435,7 +435,6 @@ struct Q_QML_PRIVATE_EXPORT Document
     int indexOfRootObject;
     QVector<Object*> objects;
     QV4::Compiler::JSUnitGenerator jsGenerator;
-    quint32 unitFlags;
 
     QQmlRefPointer<QV4::CompiledData::CompilationUnit> javaScriptCompilationUnit;
 
diff --git a/src/qml/compiler/qv4compilationunitmapper_win.cpp b/src/qml/compiler/qv4compilationunitmapper_win.cpp
index 7e62cbfe8b..6c2f36e7a0 100644
--- a/src/qml/compiler/qv4compilationunitmapper_win.cpp
+++ b/src/qml/compiler/qv4compilationunitmapper_win.cpp
@@ -94,9 +94,14 @@ CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, co
     if (!verifyHeader(&header, sourcePath, errorString))
         return nullptr;
 
+    const uint mappingFlags = header.flags & QV4::CompiledData::Unit::ContainsMachineCode
+                              ? PAGE_EXECUTE_READ : PAGE_READONLY;
+    const uint viewFlags = header.flags & QV4::CompiledData::Unit::ContainsMachineCode
+                           ? (FILE_MAP_READ | FILE_MAP_EXECUTE) : FILE_MAP_READ;
+
     // Data structure and qt version matched, so now we can access the rest of the file safely.
 
-    HANDLE fileMappingHandle = CreateFileMapping(handle, 0, PAGE_EXECUTE_READ, 0, 0, 0);
+    HANDLE fileMappingHandle = CreateFileMapping(handle, 0, mappingFlags, 0, 0, 0);
     if (!fileMappingHandle) {
         *errorString = qt_error_string(GetLastError());
         return false;
@@ -106,7 +111,7 @@ CompiledData::Unit *CompilationUnitMapper::open(const QString &cacheFileName, co
         CloseHandle(fileMappingHandle);
     });
 
-    dataPtr = MapViewOfFile(fileMappingHandle, FILE_MAP_READ | FILE_MAP_EXECUTE, 0, 0, 0);
+    dataPtr = MapViewOfFile(fileMappingHandle, viewFlags, 0, 0, 0);
     if (!dataPtr) {
         *errorString = qt_error_string(GetLastError());
         return nullptr;
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index a6ca1594a4..b71c1d8185 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -71,7 +71,7 @@
 QT_BEGIN_NAMESPACE
 
 // Bump this whenever the compiler data structures change in an incompatible way.
-#define QV4_DATA_STRUCTURE_VERSION 0x02
+#define QV4_DATA_STRUCTURE_VERSION 0x03
 
 class QIODevice;
 class QQmlPropertyCache;
@@ -619,7 +619,8 @@ struct Unit
         IsQml = 0x2,
         StaticData = 0x4, // Unit data persistent in memory?
         IsSingleton = 0x8,
-        IsSharedLibrary = 0x10 // .pragma shared?
+        IsSharedLibrary = 0x10, // .pragma shared?
+        ContainsMachineCode = 0x20 // used to determine if we need to mmap with execute permissions
     };
     LEUInt32 flags;
     LEUInt32 stringTableSize;
diff --git a/src/qml/compiler/qv4compiler.cpp b/src/qml/compiler/qv4compiler.cpp
index 50ade2c6e5..c6a872cc34 100644
--- a/src/qml/compiler/qv4compiler.cpp
+++ b/src/qml/compiler/qv4compiler.cpp
@@ -364,6 +364,7 @@ QV4::CompiledData::Unit QV4::Compiler::JSUnitGenerator::generateHeader(QV4::Comp
     CompiledData::Unit unit;
     memcpy(unit.magic, CompiledData::magic_str, sizeof(unit.magic));
     unit.flags = QV4::CompiledData::Unit::IsJavascript;
+    unit.flags |= irModule->unitFlags;
     unit.version = QV4_DATA_STRUCTURE_VERSION;
     unit.qtVersion = QT_VERSION;
     unit.architectureIndex = registerString(QSysInfo::buildAbi());
diff --git a/src/qml/compiler/qv4jsir_p.h b/src/qml/compiler/qv4jsir_p.h
index 51b8797862..73aa6c4975 100644
--- a/src/qml/compiler/qv4jsir_p.h
+++ b/src/qml/compiler/qv4jsir_p.h
@@ -934,6 +934,7 @@ struct Q_QML_PRIVATE_EXPORT Module {
     QString fileName;
     qint64 sourceTimeStamp;
     bool isQmlModule; // implies rootFunction is always 0
+    uint unitFlags; // flags merged into CompiledData::Unit::flags
 #ifdef QT_NO_QML_DEBUGGER
     static const bool debugMode = false;
 #else
@@ -946,6 +947,7 @@ struct Q_QML_PRIVATE_EXPORT Module {
         : rootFunction(0)
         , sourceTimeStamp(0)
         , isQmlModule(false)
+        , unitFlags(0)
 #ifndef QT_NO_QML_DEBUGGER
         , debugMode(debugMode)
     {}