Use of (void) before a function call [duplicate]

Question

Possible Duplicate:
casting unused return values to void

What is the purpose of (void) before a function call, for example

(void)func1(); 

I assume this is the same as simply calling func1();

Therefore is the (void) call simply to let other programmers know that the return type will be ignored, for instance if func1() had a return type of int, or does the compiler perhaps perform some optimizations on the function? Perhaps there is another reason behind it altogether - is it even legal C++ or perhaps is it a remnant of C seen in some legacy code.

Thanks

Answer 1

It prevents warning if some function are declared with attribute : "Warn if return value not used/checked"

Maybe a duplicate of Warning: ignoring return value of 'scanf', declared with attribute warn_unused_result

Check the documentation of gcc : http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html (warn_unused_result) for more details