How can I enable -Werror using a GCC pragma?

Question

I have a few files where I'd like to be strict about warnings, and I use GCC to build my project.

I've tried #pragma GCC diagnostic error "-Wall" as per 6.57.10 Diagnostic Pragmas, but it fails to account for some other enabled warning types:

foo.c:666:6: warning: passing argument 2 of 'bar' from incompatible pointer type [-Wincompatible-pointer-types]

Is there a way to enable -Werror for the file like it was supplied from the command line (or, at least, for the implicitly enabled set of warnings), so any warning would trigger an error?

Answer 1

For this case, you can use

#pragma GCC diagnostic error "-Wincompatible-pointer-types"

as for example in

#pragma GCC diagnostic error "-Wincompatible-pointer-types"
void foo(int * a)
{
}

void bar() {
        foo("foo");
}

Using -Wall with this pragma is not supported. Only diagnostic options are supported, that are shown with -fdiagnostics-show-option (which is the default today anyway), as in your example warning above.