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.

module bug23;
extern(C) int printf(char*, ...);

void main()
{
    int i;
    delegate {
        i++;
        delegate {
            i++;
        }();
    }();
    printf("%d\n", i);
    assert(i == 2);
}