File ignore-case-multibyte-non-utf8.patch of Package grep.35702

From c7c8bcdefe7be5f59a242eea63df7f64eacb6a09 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering@fb.com>
Date: Wed, 19 Feb 2014 19:31:43 -0800
Subject: [PATCH] grep -i: avoid a performance regression in multibyte non-UTF8
 locales

* src/main.c: Include dfa.h.
(trivial_case_ignore): Perform this optimization only for UTF8 locales.
This rectifies a 100-200x performance regression in non-UTF8 multi-byte
locales like ja_JP.eucJP.  The regression was introduced by the 10x
UTF8/grep-i speedup, commit v2.16-4-g97318f5.
Reported by Norihiro Tanaka in http://debbugs.gnu.org/16232#50

diff --git a/src/main.c b/src/main.c
index bd20297..56ec6b3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -34,6 +34,7 @@
 #include "c-ctype.h"
 #include "closeout.h"
 #include "colorize.h"
+#include "dfa.h"
 #include "error.h"
 #include "exclude.h"
 #include "exitfail.h"
@@ -1883,6 +1884,11 @@ static bool
 trivial_case_ignore (size_t len, char const *keys,
                      size_t *new_len, char **new_keys)
 {
+  /* Perform this translation only for UTF-8.  Otherwise, this would induce
+     a 100-200x performance penalty for non-UTF8 multibyte locales.  */
+  if ( ! using_utf8 ())
+    return false;
+
   /* FIXME: consider removing the following restriction:
      Reject if KEYS contain ASCII '\\' or '['.  */
   if (memchr (keys, '\\', len) || memchr (keys, '[', len))
-- 
2.26.2