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 g;

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

void func(char[] str)
{
    printf("%.*s\n", str.length, str.ptr);
}

void main()
{
    char[] arr = "Hello World!";
    func(arr);
    func("ditto");
}