#line 1 "not-str-lit"
	void __cgo_f_1_5(void) { static const char __cgo_undefined__5[] = (foo); }

This program will not compile, but cgo can use the presence or absence
of an error message on a given line to deduce the information it
needs. The program is syntactically valid regardless of whether each
name is a type or an ordinary identifier, so there will be no syntax
errors that might stop parsing early.