Compiler Warning (level 1) C4391

 

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The latest version of this topic can be found at Compiler Warning (level 1) C4391.

signature' : incorrect return type for intrinsic function, expected 'type'

A function declaration for a compiler intrinsic had the wrong return type. The resulting image may not run correctly.

To fix this warning, either correct the declaration or delete the declaration and simply #include the appropriate header file.

The following sample generates C4391:

// C4391.cpp  
// compile with: /W1  
// processor: x86  
// uncomment the following line and delete the line that  
// generated the warning to resolve  
// #include "xmmintrin.h"  
  
#ifdef  __cplusplus  
extern "C" {  
#endif  
  
extern void _mm_load_ss(float *p);   // C4391  
  
#ifdef  __cplusplus  
}  
#endif  
  
int main()  
{  
}  

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