From: Kirk McKusick <mckusick@ucbvax.Berkeley.EDU>
Date: Sat, 13 Nov 1982 11:02:03 +0000 (-0800)
Subject: local jumps to globally declared labels must still use jmp instead of jbr
X-Git-Tag: BSD-4_1c_2-Snapshot-Development~1871
X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/commitdiff_plain/b3f9e9d3b36a6186cae9717b5749167e1cde6953

local jumps to globally declared labels must still use jmp instead of jbr

SCCS-vsn: usr.bin/pascal/src/lab.c 1.16
---

diff --git a/usr/src/usr.bin/pascal/src/lab.c b/usr/src/usr.bin/pascal/src/lab.c
index 3e249fc07d..0b4e9778e7 100644
--- a/usr/src/usr.bin/pascal/src/lab.c
+++ b/usr/src/usr.bin/pascal/src/lab.c
@@ -1,6 +1,6 @@
 /* Copyright (c) 1979 Regents of the University of California */
 
-static char sccsid[] = "@(#)lab.c 1.15 %G%";
+static char sccsid[] = "@(#)lab.c 1.16 %G%";
 
 #include "whoami.h"
 #include "0.h"
@@ -138,7 +138,17 @@ gotoop(s)
 		     *	local goto.
 		     */
 		extlabname( extname , p -> symbol , bn );
-		putprintf( "	jbr	%s" , 0 , extname );
+		    /*
+		     *	this is a jmp because it's a jump to a label that
+		     *	has been declared global. Although this branch is
+		     *	within this module the assembler will complain that
+		     *	the destination is a global symbol. The complaint
+		     *	arises because the assembler doesn't change jbr's
+		     *	into jmp's and consequently may cause a branch 
+		     *	displacement overflow when the module is subsequently
+		     *	linked into the rest of the program.
+		     */
+		putprintf( "	jmp	%s" , 0 , extname );
 	    } else {
 		    /*
 		     *	Non-local goto.