Thread: Linking errors with static var

Just a quick question here, because I haven't had time to figure it out yet.
Here are the errors:

Code:

4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<char>::PointerInfo *,struct CMemoryManager<char>::PointerInfo *> CMemoryManager<char>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@D@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@D@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CFileMap>::PointerInfo *,struct CMemoryManager<class CFileMap>::PointerInfo *> CMemoryManager<class CFileMap>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCFileMap@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCFileMap@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CAudioProfile>::PointerInfo *,struct CMemoryManager<class CAudioProfile>::PointerInfo *> CMemoryManager<class CAudioProfile>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCAudioProfile@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCAudioProfile@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CError>::PointerInfo *,struct CMemoryManager<class CError>::PointerInfo *> CMemoryManager<class CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@@@@PAU12@@@A)
4>ExtractVideo.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CError>::PointerInfo *,struct CMemoryManager<class CError>::PointerInfo *> CMemoryManager<class CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CKantanAnimeDlg::CError>::PointerInfo *,struct CMemoryManager<class CKantanAnimeDlg::CError>::PointerInfo *> CMemoryManager<class CKantanAnimeDlg::CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@CKantanAnimeDlg@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@CKantanAnimeDlg@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CAskDefaultAction>::PointerInfo *,struct CMemoryManager<class CAskDefaultAction>::PointerInfo *> CMemoryManager<class CAskDefaultAction>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCAskDefaultAction@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCAskDefaultAction@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CChooseStream>::PointerInfo *,struct CMemoryManager<class CChooseStream>::PointerInfo *> CMemoryManager<class CChooseStream>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCChooseStream@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCChooseStream@@@@PAU12@@@A)
4>Kantan AnimeDlg.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CKantanAnimeDlg::CGUITask>::PointerInfo *,struct CMemoryManager<class CKantanAnimeDlg::CGUITask>::PointerInfo *> CMemoryManager<class CKantanAnimeDlg::CGUITask>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCGUITask@CKantanAnimeDlg@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCGUITask@CKantanAnimeDlg@@@@PAU12@@@A)
4>Kantan Anime.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CKantanAnimeDlg::CGUITask>::PointerInfo *,struct CMemoryManager<class CKantanAnimeDlg::CGUITask>::PointerInfo *> CMemoryManager<class CKantanAnimeDlg::CGUITask>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCGUITask@CKantanAnimeDlg@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCGUITask@CKantanAnimeDlg@@@@PAU12@@@A)
4>Kantan Anime.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CRect>::PointerInfo *,struct CMemoryManager<class CRect>::PointerInfo *> CMemoryManager<class CRect>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCRect@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCRect@@@@PAU12@@@A)
4>AvisynthWriter.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CAvisynthWriter::CError>::PointerInfo *,struct CMemoryManager<class CAvisynthWriter::CError>::PointerInfo *> CMemoryManager<class CAvisynthWriter::CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@CAvisynthWriter@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@CAvisynthWriter@@@@PAU12@@@A)
4>CLIWrapper.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CCLIWrapper::CError>::PointerInfo *,struct CMemoryManager<class CCLIWrapper::CError>::PointerInfo *> CMemoryManager<class CCLIWrapper::CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@CCLIWrapper@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@CCLIWrapper@@@@PAU12@@@A)
4>ConvertFile.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CCLIWrapper::CError>::PointerInfo *,struct CMemoryManager<class CCLIWrapper::CError>::PointerInfo *> CMemoryManager<class CCLIWrapper::CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@CCLIWrapper@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@CCLIWrapper@@@@PAU12@@@A)
4>ExtractAudio.obj : error LNK2001: unresolved external symbol "protected: static class CMap<void *,void *,struct CMemoryManager<class CExtractAudio::CError>::PointerInfo *,struct CMemoryManager<class CExtractAudio::CError>::PointerInfo *> CMemoryManager<class CExtractAudio::CError>::m_InfoMap" (?m_InfoMap@?$CMemoryManager@VCError@CExtractAudio@@@@1V?$CMap@PAXPAXPAUPointerInfo@?$CMemoryManager@VCError@CExtractAudio@@@@PAU12@@@A)

This is no doubt because the class CMemoryManager tries to access the static variable:

Code:

	struct PointerInfo
	{
		DWORD* pdwRefCount;
		bool bArray;
		bool bThreadSafe;
		CCriticalSection cSync;
	};

	T* p;
	PointerInfo* m_pInfo;
	static CMap<void*, void*, PointerInfo*, PointerInfo*> m_InfoMap;

It tries to access m_InfoMap, but the linker says it can't find the symbol.
Example code:

Code:

		CMemoryManager::m_InfoMap.Lookup(p, pInfo);
		CMemoryManager::m_InfoMap.SetAt(p, pInfo);

Errors like this are usually a pain to figure out and I don't have time to figure it out right so I thought I could give you all a chance

Originally Posted by Elysia

I don't have time to figure it out right so I thought I could give you all a chance

That's really nice of you. .... guess I have figured it out.
Kurt

Please tell me then

Looks like you have just declared the static var but not created it in any of the implementation files.
Kurt

Try something like this

Code:

#include <map>
using std::map;

template <class T>
class test {
public:
    void set(int idx, const T & t ) { statmap[idx]=t; }
private:
    static map<int, T> statmap;
};

template<class T>
map<int, T> test<T>::statmap;

int main() {
    test<int> ti;
    ti.set(3, 4);
}

Kurt

You can keep the definition of the static variable in the header (outside the class declaration ). Most compilers nowadays should handle that allright.
Kurt

Originally Posted by ZuK

You can keep the definition of the static variable in the header (outside the class declaration ). Most compilers nowadays should handle that allright.
Kurt

YES! That does the trick!
Thanks a bunch, cudos to you and a big finger to the compiler.