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.

interface IN
{
    void func();
}
abstract class AC
{
    abstract void func();
    long ll;
}
class C : AC
{
    void func()
    {
    }
}

void main()
{
    scope c = new C;
}