struct S {
	// works with double and long as well
	real a = 0, b = 0;
}

void func (S s = S()) {
	writefln("hello world");
}

void main () {
	func();
}

It appears that using "= S()" as a default parameter causes a compiler error if S contains default initializers for types larger than a register (32 bits, e.g. double, real, and long).

Full compiler error is "Internal error: ..\ztc\cgcod.c 1594"