From 8777759f593be7af2a0266e0b871aa0af3200962 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Wed, 2 Dec 2009 23:23:11 -0800
Subject: [PATCH] gc: make 'invalid rune in string' a little less cryptic

Fixes #371.

R=ken2
https://golang.org/cl/164091
---
 src/cmd/gc/lex.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/cmd/gc/lex.c b/src/cmd/gc/lex.c
index f858aa95ec..c202f3ecdc 100644
--- a/src/cmd/gc/lex.c
+++ b/src/cmd/gc/lex.c
@@ -1065,7 +1065,9 @@ loop:
 		goto loop;
 	c = chartorune(&rune, str);
 	if(rune == Runeerror && c == 1) {
-		yyerror("illegal rune in string");
+		lineno = lexlineno;
+		yyerror("illegal UTF-8 sequence in comment or string");
+		flusherrors();
 		for(c=0; c<i; c++)
 			print(" %.2x", *(uchar*)(str+c));
 		print("\n");
-- 
2.50.0