3685 – Regression(D1 only): DMD silently exits on valid code

There's two things wrong with this:
1. it rejects valid code
2. it doesn't output an error message, it only does exit(1)
//fails to compile with 1.055 (dmd silently exits)
//succeeds with 1.053 (successfully compiles)
void x(T)() {
 static assert(false);
}
template y(T) {
 const bool y = is(typeof( { x!(T)(); } ));
}
static assert(!y!(int));

*** Issue 3691 has been marked as a duplicate of this issue. ***

This is a trivial.
D1 template.c, line 3500.
	error("error instantiating");
	if (tinst)
	{ tinst->printInstantiationTrace();
+	 if (!global.gag) 
	 fatal();
	}

Changeset 351

fixed dmd 1.056