compiler-warning-level-1-c4178.md

description	title	ms.date	f1_keywords	helpviewer_keywords
Learn more about: Compiler Warning (level 1) C4178	Compiler Warning (level 1) C4178	03/06/2024	C4178	C4178

Compiler Warning (level 1) C4178

case constant 'constant' too big for the type of the switch expression

A case constant in a switch expression does not fit in the type to which it is assigned.

Example

// C4178.cpp
// compile with: /W1 /permissive
int main()
{
    unsigned int u = 1;
    switch (u)
    {
    case 4294967295:   // OK, maximum value for type unsigned int
        break;
    case 4294967296:   // C4178, exceeded maximum value
        break;
    }
}