The best is not to disable (i.e. ignore) the linker warning, but fix the issue that the linker is prompting: the LNK4049 warning means that you have declare something as __declspec(dllexport) inside a module of your project, and as __declspec(dllimport) on another module of the same project.

If what you want is to reference something that you have instantiated on another module (i.e. another .c or .cpp file), simply declare it using extern.

If you really need to import or export that symbol to/from another executable, you should declare the symbol with the same linkage on both your modules (i.e. or as __declspec(dllexport) on both, or as __declspec(dllimport) on both).

Instead of using __declspec(dllimport) and __declspec(dllexport) in header file, which would (most probably) be common for both DLL and the EXE (or another DLL); you can define a common macro:

#ifdef DLL_PROJECT
#define IMPORT_EXPORT __declspec(dllexport)
#else
#define IMPORT_EXPORT __declspec(dllimport)
#endif

For the you need to define DLL_PROJECT in DLL project. You should name this macro to something meaningful, like MP3CODEC_DLL, so that it doesn''t *** with some other projects/header files:

#ifdef MP3CODEC_DLL
#define CODEC_IMPORT_EXPORT __declspec(dllexport)
#else
#define CODEC_IMPORT_EXPORT __declspec(dllimport)
#endif</pre>

And then use CODEC_IMPORT_EXPORT in your header file.

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