I compiled latest Qt branch 4.7 (4.7.4) from Git repository with out any error.
by the trick i fixed ABI detection issue as it is again happening.
then I tried to build "QML Dump, Qml Debugging Helpers."
First two compiled successfully but third one which is the "QML Observer" failed to build.

Here is the error :::
@main.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static void __cdecl QDeclarativeDebugHelper::enableDebugging(void)" (_imp?enableDebugging@QDeclarativeDebugHelper@@SAXXZ) referenced in function _main

QmlJSDebuggerd.lib(jsdebuggeragent.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static class QScriptEngine * __cdecl QDeclarativeDebugHelper::getScriptEngine(class QDeclarativeEngine *)" (_imp?getScriptEngine@QDeclarativeDebugHelper@@SAPAVQScriptEngine@@PAVQDeclarativeEngine@@@Z) referenced in function "public: __thiscall QmlJSDebugger::JSDebuggerAgent::JSDebuggerAgent(class QDeclarativeEngine *)" (??0JSDebuggerAgent@QmlJSDebugger@@QAE@PAVQDeclarativeEngine@@@Z)

QmlJSDebuggerd.lib(qdeclarativeviewobserver.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static void __cdecl QDeclarativeDebugHelper::setAnimationSlowDownFactor(double)" (_imp?setAnimationSlowDownFactor@QDeclarativeDebugHelper@@SAXN@Z) referenced in function "private: void __thiscall QmlJSDebugger::QDeclarativeViewObserver::animationSpeedChangeRequested(double)" (?animationSpeedChangeRequested@QDeclarativeViewObserver@QmlJSDebugger@@AAEXN@Z)

debug\qmlobserver.exe : fatal error LNK1120: 3 unresolved externals@

Any idea how to fix it and where it comes from ?

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