Compiler Warning (level 4) C4210
Visual Studio 2015
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The latest version of this topic can be found at Compiler Warning (level 4) C4210.
nonstandard extension used : function given file scope
With the default Microsoft extensions (/Ze), function declarations have file scope.
// C4210.c
// compile with: /W4 /c
void func1()
{
extern int func2( double ); // C4210 expected
}
int main()
{
func2( 4 ); // /Ze passes 4 as type double
} // /Za passes 4 as type int
This extension can prevent your code from being portable to other compilers.
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