Assess Violation in Qt5WebKitd.dll!WebCore::addToTextEncodingNameMap(const char * alias, const char * name): Assistant and Designer Crashes before a window is shown (MSVC 2012.2 bug?)

Qt 5.0.1 is built with Visual Studio 2012 Update 2 (CTP4)

Qt 5.0.1 built as release or debug & release (optimization enabled), Designer and Assistant.exe crash during startup before a window is show. When Qt is compiled without webkit, both exetutables run as expected.

To reproduce it:

• use qt. 5.0.1
• use MSVC 2012 Update 2 (important to reproduce, since it seems to be compiler related. The bug is still not fixed in MSVC Update2 CTP4)!!
  -Compile Qt WITH webkit.
• compile only as debug, but add /O2 to the compiler to enable optimization. This triggers the error and includes debug information for debugging puposes.

Since MSVC 2012 is quite new, and the Update1 had some errors in code optimization, it is very likely that it is again a bug on the MS side.
However, since Update 2 will be released in some weeks, we should hurry to identify whether it is a webkit bug or a bug in MS VS 2012 to report the bug to MS, maybe they fix it until RTM.
(edit: VS 2012 was released on April 4th and the bug is still there)

I compiled with the newest CTP (CTP4).

debugging assistant.exe reveales the following callstack ( "Zeile" means row):
Qt5WebKitd.dll!WebCore::addToTextEncodingNameMap(const char * alias, const char * name) Zeile 174 C++
Qt5WebKitd.dll!WebCore::TextCodecLatin1::registerEncodingNames(void (const char *, const char *) * registrar) Zeile 81 C++
Qt5WebKitd.dll!WebCore::buildBaseTextCodecMaps() Zeile 221 C++
Qt5WebKitd.dll!WebCore::atomicCanonicalTextEncodingName(const char * name) Zeile 338 C++
Qt5WebKitd.dll!WebCore::TextEncoding::TextEncoding(const char * name) Zeile 58 C++
Qt5WebKitd.dll!WebCore::UTF8Encoding() Zeile 252 C++
Qt5WebKitd.dll!WebCore::KURL::KURL(const QUrl & url) Zeile 32 C++
Qt5WebKitd.dll!QWebSettingsPrivate::apply() Zeile 219 C++
Qt5WebKitd.dll!QWebSettings::QWebSettings(WebCore::Settings * settings) Zeile 560 C++
Qt5WebKitd.dll!QWebPageAdapter::initializeWebCorePage() Zeile 210 C++
Qt5WebKitWidgetsd.dll!QWebPagePrivate::QWebPagePrivate(QWebPage * qq) Zeile 205 C++
Qt5WebKitWidgetsd.dll!QWebPage::QWebPage(QObject * parent) Zeile 1354 C++
Qt5WebKitWidgetsd.dll!QWebView::settings() Zeile 388 C++
assistant.exe!HelpViewer::HelpViewer(double zoom, QWidget * parent) Zeile 266 C++
assistant.exe!OpenPagesModel::addPage(const QUrl & url, double zoom) Zeile 84 C++
assistant.exe!OpenPagesManager::setupInitialPages(bool defaultCollection, const QUrl & cmdLineUrl) Zeile 155 C++
assistant.exe!OpenPagesManager::OpenPagesManager(QObject * parent, bool defaultCollection, const QUrl & cmdLineUrl) Zeile 99 C++
assistant.exe!OpenPagesManager::createInstance(QObject * parent, bool defaultCollection, const QUrl & cmdLineUrl) Zeile 65 C++
assistant.exe!MainWindow::MainWindow(CmdLineParser * cmdLine, QWidget * parent) Zeile 161 C++
assistant.exe!main(int argc, char * * argv) Zeile 434 C++
assistant.exe!WinMain(HINSTANCE__ * instance, HINSTANCE__ * prevInstance, char * __formal, int cmdShow) Zeile 135 C++
assistant.exe!__tmainCRTStartup() Zeile 528 C
assistant.exe!WinMainCRTStartup() Zeile 377 C

Designer.exe crashes in the same function:
Qt5WebKitd.dll!WebCore::addToTextEncodingNameMap(const char * alias, const char * name) Zeile 174 C++
Qt5WebKitd.dll!WebCore::TextCodecLatin1::registerEncodingNames(void (const char *, const char *) * registrar) Zeile 81 C++
Qt5WebKitd.dll!WebCore::buildBaseTextCodecMaps() Zeile 221 C++
Qt5WebKitd.dll!WebCore::atomicCanonicalTextEncodingName(const char * name) Zeile 338 C++
Qt5WebKitd.dll!WebCore::TextEncoding::TextEncoding(const char * name) Zeile 58 C++
Qt5WebKitd.dll!WebCore::UTF8Encoding() Zeile 252 C++
Qt5WebKitd.dll!WebCore::KURL::KURL(const QUrl & url) Zeile 32 C++
Qt5WebKitd.dll!QWebSettingsPrivate::apply() Zeile 219 C++
Qt5WebKitd.dll!QWebSettings::QWebSettings(WebCore::Settings * settings) Zeile 560 C++
Qt5WebKitd.dll!QWebPageAdapter::initializeWebCorePage() Zeile 210 C++
Qt5WebKitWidgetsd.dll!QWebPagePrivate::QWebPagePrivate(QWebPage * qq) Zeile 205 C++
Qt5WebKitWidgetsd.dll!QWebPage::QWebPage(QObject * parent) Zeile 1354 C++
Qt5WebKitWidgetsd.dll!QWebView::textSizeMultiplier() Zeile 607 C++
Qt5WebKitWidgetsd.dll!QWebView::qt_metacall(QMetaObject::Call _c, int _id, void * * _a) Zeile 277 C++
Qt5Cored.dll!QMetaObject::metacall(QObject * object, QMetaObject::Call cl, int idx, void * * argv) Zeile 307 C++
Qt5Cored.dll!QMetaProperty::read(const QObject * object) Zeile 2821 C++
Qt5Designerd.dll!`anonymous namespace'::QDesignerMetaProperty::read(const QObject * object) Zeile 125 C++
Qt5Designerd.dll!QDesignerPropertySheet::metaProperty(int index) Zeile 1088 C++
Qt5Designerd.dll!QDesignerPropertySheet::property(int index) Zeile 1079 C++
Qt5Designerd.dll!qdesigner_internal::WidgetDataBase::defaultPropertyValues(const QString & name) Zeile 455 C++
Qt5Designerd.dll!qdesigner_internal::WidgetDataBase::grabDefaultPropertyValues() Zeile 467 C++
designer.exe!QDesignerWorkbench::QDesignerWorkbench() Zeile 194 C++
designer.exe!QDesigner::initialize() Zeile 241 C++
designer.exe!QDesigner::QDesigner(int & argc, char * * argv) Zeile 98 C++
designer.exe!main(int argc, char * * argv) Zeile 55 C++
designer.exe!WinMain(HINSTANCE__ * instance, HINSTANCE__ * prevInstance, char * __formal, int cmdShow) Zeile 135 C++
designer.exe!__tmainCRTStartup() Zeile 528 C
designer.exe!WinMainCRTStartup() Zeile 377 C