Factor out the code to find gcc, and add a command-line option to override the default executable name. This should help cross-compilation by allowing a cross-gcc to be specified from the configuration file instead of only through the CC environment variable.

struct bar {
    int bar;
}

void main() {
    bar Bar;
    with (Bar)
    {
        assert(Bar.bar == 0);
        void test()
        {
            bar ++;
        }
        test();
    }
    assert(Bar.bar == 1);
}