Compiler Warning (level 4) C4559


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The latest version of this topic can be found at Compiler Warning (level 4) C4559.

function' : redefinition; the function gains __declspec(modifier)

A function was redefined or redeclared and the second definition or declaration added a __declspec modifier (modifier). This warning is informational. To fix this warning, delete one of the definitions.

The following sample generates C4559:

// C4559.cpp  
// compile with: /W4 /LD  
void f();  
__declspec(noalias) void f();   // C4559