Virtual C++ ignore warnings

if we enable "-Wall -Werror" on Virtual C++, Virtual C++ will report all warnings and take it as error.

But you want to ignore some warnings in some cases. So we need to find a way to ignore warnings. Virtual C++ provide '#pragma warning( xxx)' to do it.

Here is the example:

#pragma warning( push )
#pragma warning( disable : 4100 )
int main(int argc, char** argv)
{
#pragma warning( pop )

#pragma warning( push )
#pragma warning( disable : 4101 )
	int a;
#pragma warning( pop )
	printf("hello world\n");
	return 0;
}

In this code, we ignore two warnings. first is 4100, second is 4101.

4100 is parameter is not used.

4101 is variable is not used.

For GCC, we use __attribute__((unused)) for both unused parameters and variables.