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 vararg5;
import tango.core.Vararg;
extern(C) int printf(char*, ...);
void func(...)
{
    char[] str = va_arg!(char[])(_argptr);
    {printf("%.*s\n", str.length, str.ptr);}
}
void main()
{
    char[] str = "hello";
    func(str);
}