Compiler Warning (level 1) C4555

The latest version of this topic can be found at Compiler Warning (level 1) C4555.

expression has no effect; expected expression with side-effect

This warning informs you when an expression has no effect.

This warning is off by default. See Compiler Warnings That Are Off by Default for more information.

For example:

// C4555.cpp  
// compile with: /W1  
#pragma warning(default:4555)  
  
void func1()  
{  
   1;   // C4555  
}  
  
void func2()  
{  
   int x;  
   x;   // C4555  
}  
  
int main()  
{  
}