C6285

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warning C6285: (<non-zero constant> || <non-zero constant>) is always a non-zero constant. Did you intend to use the bitwise-and operator?

This warning indicates that two constant values, both greater than one, were detected as arguments to a logical-or operation that occurs in a test context. This expression is always TRUE.

Constant values greater than one suggest that the arguments to logical-or could be bit fields. Consider whether a bitwise operator might be a more appropriate operator in this case.

The following code generates this warning:

#include <stdio.h>  
#define     TESTED_VALUE    0x37  
#define     MASK            0xaa  
  
void f()  
{  
  if (TESTED_VALUE || MASK)   
  {  
    puts("(TESTED_VALUE || MASK) True");  
    // code ...  
  }  
  else   
  {  
    puts("(TESTED_VALUE || MASK) False");  
    // code ...  
  }  
}  

To correct this warning, use the following code:

#include <stdio.h>  
#define     TESTED_VALUE    0x37  
#define     MASK            0xaa  
  
void f(int flag)  
{  
  if ((TESTED_VALUE & MASK)== flag)  
  {  
    puts("true");  
    // code ...  
  }  
  else  
  {  
    puts("false");  
    // code ...  
  }  
}  

Expressions with Binary Operators