cmd/compile: suppress callsite signatures if any type is unknown
Fixes #19012.
Fallback to return signatures without detailed types.
These error message will be of the form of issue:
* https://golang.org/issues/4215
* https://golang.org/issues/6750
So:
func f(x int, y uint) {
return x > y
}
f(10, "a" < 3)
will give errors:
too many errors to return
too many arguments in call to f
instead of:
too many errors to return
have (<T>)
want ()
too many arguments in call to f
have (number, <T>)
want (number, number)
Change-Id: I680abc7cdd8444400e234caddf3ff49c2d69f53d
Reviewed-on: https://go-review.googlesource.com/36806 Reviewed-by: Robert Griesemer <gri@golang.org>