From 81153b6b63d2236145b8c0fffaa52fb42874b5a0 Mon Sep 17 00:00:00 2001
From: "Andrey A. Chernov" <ache@FreeBSD.org>
Date: Fri, 19 Apr 2002 19:43:46 +0000
Subject: [PATCH] Prevent sign extension on characters with 8bit set

---
 usr.bin/m4/mdef.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/usr.bin/m4/mdef.h b/usr.bin/m4/mdef.h
index a886412012d8..46ec643320ee 100644
--- a/usr.bin/m4/mdef.h
+++ b/usr.bin/m4/mdef.h
@@ -170,7 +170,7 @@ struct input_file {
  *      pushf() - push a call frame entry onto stack
  *      pushs() - push a string pointer onto stack
  */
-#define gpbc()   (bp > bufbase) ? (*--bp ? *bp : EOF) : \
+#define gpbc()   (bp > bufbase) ? (*--bp ? (*bp & 0xFF) : EOF) : \
 	((chscratch = obtain_char(infile+ilevel)) == '\n' && \
 	++inlineno[ilevel], chscratch)
 #define pushf(x) 			\