Compiler Warning (level 4) C4389
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Compiler Warning (level 4) C4389

Error Message

'operator' : signed/unsigned mismatch

An operation involved signed and unsigned variables. This could result in a loss of data.

The following sample generates C4389:

// C4389.cpp
// compile with: /W4
#pragma warning(default: 4389)

int main()
   int a = 9;
   unsigned int b = 10;
   if (a == b)   // C4389
      return 0;
      return 0;
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