Compiler Warning (level 1) C4549

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The latest version of this topic can be found at Compiler Warning (level 1) C4549.

operator' : operator before comma has no effect; did you intend 'operator'?

The compiler detected an ill-formed comma expression.

This warning is off by default. For more information, see Compiler Warnings That Are Off by Default.

The following sample generates C4549:

// C4549.cpp  
// compile with: /W1  
#pragma warning (default : 4549)  
  
int main() {  
   int i = 0, k = 0;  
  
   if ( i == 0, k )   // C4549  
   // try the following line instead  
   // if ( i == 0 )  
      i++;  
}