__noop
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The latest version of this topic can be found at __noop.
Microsoft Specific**
The __noop intrinsic specifies that a function should be ignored and the argument list be parsed but no code be generated for the arguments. It is intended for use in global debug functions that take a variable number of arguments.
The compiler converts the __noop intrinsic to 0 at compile time.
Example
The following code shows how you could use __noop.
// compiler_intrinsics__noop.cpp
// compile with or without /DDEBUG
#include <stdio.h>
#if DEBUG
#define PRINT printf_s
#else
#define PRINT __noop
#endif
int main() {
PRINT("\nhello\n");
}