Compiler Warning (level 4) C4255


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The latest version of this topic can be found at Compiler Warning (level 4) C4255.

function' : no function prototype given: converting '()' to '(void)'

The compiler did not find an explicit list of arguments to a function. This warning is for the C compiler only.

This warning is off by default. See Compiler Warnings That Are Off by Default for more information.

The following sample generates C4255:

// C4255.c  
// compile with: /W4 /WX  
#pragma warning (default : 4255)  
void f()  { // C4255  
// try the following line instead  
//void f(void) {  
int main(int argc, char *argv[]) {