Question

I have a VS2008 C++ project which currently I compiled on VS2010.
it contains a dll and execution GUI project.

With x64 flag the dll is build without any errors but the GUI has some LNK errors to function that are in the dll. “unresolved external symbol…” (error LNK 2019 and 2001)
with Win32 flag there is no LNK errors.

for example I have the error:

unresolved external symbol "public :void _cdecl aaa::bbb(void)*(?bbb@aaa@@QEAAXXZ) referenced in function "public:__cdecl ccc::ccc(class aaa &)" (??0@@QEAA@AEAVaaa@@@Z)

I’m running on x64 OS.

Any help please?

Answer 1

As I understand it your problem is as follows:

Your solution contains a class library project and an application project of somesort that provides the user interface.

Your solution compiles without problem when set for win32 bit environment, but shows linker errors when compiled for x64 bit environment.

It is likely that your class library project output, as referenced by the GUI cannot be found when compiling for the x64 environment.

I would suggest that you try setting your configuration manager to build your class library project as x64 or Win32 to match your GUI project.

Check that your project configuration doesn’t build the class library to a directory specific to the environment type and ensure that your GUI project uses a reference to the class library project and not the output DLL.

Also check that your dll actually builds under for the x64 environment.

It may also be worth checking that your class library project doesn’t use any old Win32 specific libraries.