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Compiler Warning (level 4) C4245
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Compiler Warning (level 4) C4245

Error Message

'conversion' : conversion from 'type1' to 'type2', signed/unsigned mismatch

You tried to convert a signed const that has a negative value to an unsigned.

The following sample generates C4245:

// C4245.cpp
// compile with: /W4 /c
const int i = -1;
unsigned int j = i; // C4245

const int k = 1;
unsigned int l = k; // okay

int m = -1;
unsigned int n = m; // okay

void Test(size_t i) {}

int main() {
   Test( -19 );   // C4245

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