compiler-warning-level-1-c4804.md

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Learn more about: Compiler Warning (level 1) C4804	Compiler Warning (level 1) C4804	11/04/2016	C4804	C4804	069e8f44-3ef6-43bb-8524-4116fc6eea83

Compiler Warning (level 1) C4804

'operation' : unsafe use of type 'bool' in operation

This warning is for when you used a bool variable or value in an unexpected way. For example, C4804 is generated if you use operators such as the negative unary operator (-) or the complement operator (~). The compiler evaluates the expression.

Example

The following sample generates C4804:

// C4804.cpp
// compile with: /W1

int main()
{
   bool i = true;
   if (-i)   // C4804, remove the '-' to resolve
   {
      i = false;
   }
}