compiler-warning-level-1-c4548.md

title	Compiler Warning (level 1) C4548
description	Learn more about: Compiler Warning (level 1) C4548
ms.date	11/04/2016
f1_keywords	C4548
helpviewer_keywords	C4548

Compiler Warning (level 1) C4548

expression before comma has no effect; expected expression with side-effect

Remarks

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.

Example

The following example generates C4548:

// C4548.cpp
// compile with: /W1
#pragma warning (default : 4548)
int main()
{
   int i = 0, k = 0;

   if ( i, k )   // C4548
   // try the following line instead
   // if ( i = 0, k )
      i++;
}