2aac288c18
Errors in `DiagCtxtInner::emit_diagnostic` are never set to `Level::Bug`, because the condition never succeeds, because `self.treat_err_as_bug()` is called *before* the error counts are incremented. This commit switches to `self.treat_next_err_as_bug()`, fixing the problem. This changes the error message output to actually say "internal compiler error".