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C6287

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warning C6287: redundant code: the left and right sub-expressions are identical

This warning indicates that a redundant element was detected in an expression.

It is difficult to judge the severity of this problem without examining the code. A duplicate test on its own is harmless, but the consequences of deleting the second test can be severe. The code should be inspected to ensure that a test was not omitted.

Example

The following code generates this warning:

void f(int x)  
{  
  if ((x == 1) && (x == 1))   
  {  
    //logic   
  }  
  if ((x != 1) || (x != 1))  
  {  
    //logic  
  }  
}

The following code shows various methods to correct this warning:

void f(int x, int y)  
{  
  /* Remove the redundant sub-expression: */  
  if (x == 1)   
  {  
     // logic   
  }  
  if (x != 1)   
  {  
    // logic  
  }  
  /* or test the missing variable: */  
  if ((x == 1) && (y == 1))  
  {  
     // logic  
  }  
  if ((x != 1) || (y != 1))  
  {  
     // logic  
  }  
}