Compiler Warning (level 2) C4309


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The latest version of this topic can be found at Compiler Warning (level 2) C4309.

conversion' : truncation of constant value

The type conversion causes a constant to exceed the space allocated for it. You may need to use a larger type for the constant.

The following sample generates C4309:

// C4309.cpp  
// compile with: /W2  
int main()  
   char c = 128;   // C4309