From b676b0e125b44c53a757c327cf3c4459b9593d2a Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Mon, 22 Sep 2008 10:56:54 -0700
Subject: [PATCH] better yacc rule in Makefile

if y.tab.c is older than y.tab.h, make
interprets doing nothing as a failure,
because y.tab.c hasn't been updated.
so update it.

R=r
DELTA=4  (0 added, 0 deleted, 4 changed)
OCL=15615
CL=15622
---
 src/cmd/6a/Makefile | 2 +-
 src/cmd/cc/Makefile | 2 +-
 src/cmd/gc/Makefile | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/cmd/6a/Makefile b/src/cmd/6a/Makefile
index d4bfd210cb..db54157815 100644
--- a/src/cmd/6a/Makefile
+++ b/src/cmd/6a/Makefile
@@ -33,7 +33,7 @@ y.tab.h: $(YFILES)
 	yacc $(YFLAGS) $(YFILES)
 
 y.tab.c: y.tab.h
-	# do nothing
+	test -f y.tab.c && touch y.tab.c
 
 clean:
 	rm -f $(OFILES) $(TARG) *.6 enam.c 6.out a.out y.tab.h y.tab.c
diff --git a/src/cmd/cc/Makefile b/src/cmd/cc/Makefile
index 4247a8b971..61aec26a72 100644
--- a/src/cmd/cc/Makefile
+++ b/src/cmd/cc/Makefile
@@ -42,7 +42,7 @@ y.tab.h: $(YFILES)
 	yacc $(YFLAGS) $(YFILES)
 
 y.tab.c: y.tab.h
-	# do nothing
+	test -f y.tab.c && touch y.tab.c
 
 clean:
 	rm -f $(OFILES) *.6 enam.c 6.out a.out y.tab.h y.tab.c $(LIB)
diff --git a/src/cmd/gc/Makefile b/src/cmd/gc/Makefile
index 4a7445a91d..600c3b4420 100644
--- a/src/cmd/gc/Makefile
+++ b/src/cmd/gc/Makefile
@@ -37,7 +37,7 @@ y.tab.h: $(YFILES)
 	yacc $(YFLAGS) $(YFILES)
 
 y.tab.c: y.tab.h
-	# do nothing
+	test -f y.tab.c && touch y.tab.c
 
 sysimport.c:	sys.go mksys.bash
 	bash mksys.bash
-- 
2.48.1