Compiler Warning (level 1) C4747

 

For the latest documentation on Visual Studio 2017, see Visual Studio 2017 Documentation.

For the latest documentation on Visual Studio 2017, see Compiler Warning (level 1) C4747 on docs.microsoft.com. Calling managed 'entrypoint': Managed code may not be run under loader lock, including the DLL entrypoint and calls reached from the DLL entrypoint

The compiler found a (probable) DLL entry point compiled to MSIL. Because of potential problems with loading a DLL whose entry point has been compiled to MSIL, you are strongly discouraged from compiling a DLL entry point function to MSIL.

For more information, see Initialization of Mixed Assemblies and Linker Tools Error LNK1306.

To correct this error

  1. Do not compile the module with /clr.

  2. Mark the entry point function with #pragma unmanaged.

The following sample generates C4747.

// C4747.cpp  
// compile with: /clr /c /W1  
// C4747 expected  
#include <windows.h>  
  
// Uncomment the following line to resolve.  
// #pragma unmanaged  
  
BOOL WINAPI DllMain(HANDLE hInstance, ULONG Command, LPVOID Reserved) {  
   return TRUE;  
};  

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