patch 7.4.2080
Problem: When using PERROR() on some systems assert_fails() does not see
the error.
Solution: Make PERROR() always report the error.
diff --git a/src/proto/message.pro b/src/proto/message.pro
index 27a215d..5b70640 100644
--- a/src/proto/message.pro
+++ b/src/proto/message.pro
@@ -8,6 +8,7 @@
void reset_last_sourcing(void);
void msg_source(int attr);
int emsg_not_now(void);
+void do_perror(char *msg);
int emsg(char_u *s);
int emsg2(char_u *s, char_u *a1);
void emsg_invreg(int name);