Stop automatically regenerating gap.o (and hence linking a new kernel)

whenever make is issued. Only do this when there are actual source changes
below /sys. This restores the behavior prior to the KARL implementation.

Problem noticed and patiently explained by mpi
implementation with a lot of help from espie

ok mpi, espie, deraadt

15 files changed, 79 insertions, 54 deletions

diff --git a/sys/arch/alpha/conf/Makefile.alpha b/sys/arch/alpha/conf/Makefile.alpha
index 68f14852112..55f197b123a 100644
--- a/sys/arch/alpha/conf/Makefile.alpha
+++ b/sys/arch/alpha/conf/Makefile.alpha
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.alpha,v 1.105 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.alpha,v 1.106 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -124,8 +124,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0x00000000
+MAKE_GAP = LD="${LD}" sh makegap.sh 0x00000000
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -160,7 +162,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/amd64/conf/Makefile.amd64 b/sys/arch/amd64/conf/Makefile.amd64
index c9bf466cb29..d223eaa7ac7 100644
--- a/sys/arch/amd64/conf/Makefile.amd64
+++ b/sys/arch/amd64/conf/Makefile.amd64
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.amd64,v 1.88 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.amd64,v 1.89 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -127,8 +127,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0xcccccccc
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xcccccccc
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -164,7 +166,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/arm64/conf/Makefile.arm64 b/sys/arch/arm64/conf/Makefile.arm64
index 8273e7473ff..dda6c278953 100644
--- a/sys/arch/arm64/conf/Makefile.arm64
+++ b/sys/arch/arm64/conf/Makefile.arm64
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.arm64,v 1.19 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.arm64,v 1.20 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -130,8 +130,10 @@ gapdummy.o:
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh gapdummy.o
-	LD="${LD}" sh makegap.sh 0xd4d4d4d4 gapdummy.o
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xd4d4d4d4 gapdummy.o
+
+gap.o:	Makefile makegap.sh gapdummy.o vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -168,7 +170,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/armv7/conf/Makefile.armv7 b/sys/arch/armv7/conf/Makefile.armv7
index 8158039bf82..e9facce71d9 100644
--- a/sys/arch/armv7/conf/Makefile.armv7
+++ b/sys/arch/armv7/conf/Makefile.armv7
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.armv7,v 1.32 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.armv7,v 1.33 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -129,8 +129,10 @@ gapdummy.o:
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh gapdummy.o
-	LD="${LD}" sh makegap.sh 0xffffffff gapdummy.o
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xffffffff gapdummy.o
+
+gap.o:	Makefile makegap.sh gapdummy.o vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -167,7 +169,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/hppa/conf/Makefile.hppa b/sys/arch/hppa/conf/Makefile.hppa
index f705883c6b5..191548a4a3e 100644
--- a/sys/arch/hppa/conf/Makefile.hppa
+++ b/sys/arch/hppa/conf/Makefile.hppa
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.hppa,v 1.99 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.hppa,v 1.100 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -132,8 +132,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0x00000000	# BREAK 0,0 -> trap
+MAKE_GAP = LD="${LD}" sh makegap.sh 0x00000000	# BREAK 0,0 -> trap
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -169,7 +171,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/i386/conf/Makefile.i386 b/sys/arch/i386/conf/Makefile.i386
index ea1047528b8..73c452dbcec 100644
--- a/sys/arch/i386/conf/Makefile.i386
+++ b/sys/arch/i386/conf/Makefile.i386
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.i386,v 1.114 2017/07/16 16:47:06 visa Exp $
+#	$OpenBSD: Makefile.i386,v 1.115 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -128,8 +128,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0xcccccccc
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xcccccccc
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -165,7 +167,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/landisk/conf/Makefile.landisk b/sys/arch/landisk/conf/Makefile.landisk
index b3a8dd98dec..c570cb90264 100644
--- a/sys/arch/landisk/conf/Makefile.landisk
+++ b/sys/arch/landisk/conf/Makefile.landisk
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.landisk,v 1.71 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.landisk,v 1.72 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -124,8 +124,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0xc3c3c3c3
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xc3c3c3c3
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -161,7 +163,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/loongson/conf/Makefile.loongson b/sys/arch/loongson/conf/Makefile.loongson
index 3ffc0ab34dd..f38c5139564 100644
--- a/sys/arch/loongson/conf/Makefile.loongson
+++ b/sys/arch/loongson/conf/Makefile.loongson
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.loongson,v 1.64 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.loongson,v 1.65 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -133,8 +133,10 @@ gapdummy.o:
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh gapdummy.o
-	LD="${LD}" sh makegap.sh 0xefefefef gapdummy.o
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xefefefef gapdummy.o
+
+gap.o:	Makefile makegap.sh gapdummy.o vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -175,7 +177,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/luna88k/conf/Makefile.luna88k b/sys/arch/luna88k/conf/Makefile.luna88k
index c426fa42271..a4dc9aac14a 100644
--- a/sys/arch/luna88k/conf/Makefile.luna88k
+++ b/sys/arch/luna88k/conf/Makefile.luna88k
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.luna88k,v 1.71 2017/06/29 16:51:35 espie Exp $
+#	$OpenBSD: Makefile.luna88k,v 1.72 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -156,7 +156,7 @@ install-kernel-${MACHINE_NAME}:
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/macppc/conf/Makefile.macppc b/sys/arch/macppc/conf/Makefile.macppc
index ef48cbb94ff..5a5b3a6f468 100644
--- a/sys/arch/macppc/conf/Makefile.macppc
+++ b/sys/arch/macppc/conf/Makefile.macppc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.macppc,v 1.88 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.macppc,v 1.89 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -124,8 +124,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0x00000000	# guaranteed illegal
+MAKE_GAP = LD="${LD}" sh makegap.sh 0x00000000	# guaranteed illegal
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -161,7 +163,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/octeon/conf/Makefile.octeon b/sys/arch/octeon/conf/Makefile.octeon
index f6d29788eab..e1b8f27062a 100644
--- a/sys/arch/octeon/conf/Makefile.octeon
+++ b/sys/arch/octeon/conf/Makefile.octeon
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.octeon,v 1.40 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.octeon,v 1.41 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -134,8 +134,10 @@ gapdummy.o:
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh gapdummy.o
-	LD="${LD}" sh makegap.sh 0xefefefef gapdummy.o
+MAKE_GAP = LD=${LD} sh makegap.sh 0xefefefef gapdummy.o
+
+gap.o:	Makefile makegap.sh gapdummy.o vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -176,7 +178,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/sgi/conf/Makefile.sgi b/sys/arch/sgi/conf/Makefile.sgi
index 3ebf12dbab1..7d70a7c2072 100644
--- a/sys/arch/sgi/conf/Makefile.sgi
+++ b/sys/arch/sgi/conf/Makefile.sgi
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.sgi,v 1.88 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.sgi,v 1.89 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -133,8 +133,10 @@ gapdummy.o:
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh gapdummy.o
-	LD="${LD}" sh makegap.sh 0xefefefef gapdummy.o
+MAKE_GAP = LD="${LD}" sh makegap.sh 0xefefefef gapdummy.o
+
+gap.o:	Makefile makegap.sh gapdummy.o vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -176,7 +178,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/socppc/conf/Makefile.socppc b/sys/arch/socppc/conf/Makefile.socppc
index db46fd816ab..a3f2b6a25b8 100644
--- a/sys/arch/socppc/conf/Makefile.socppc
+++ b/sys/arch/socppc/conf/Makefile.socppc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.socppc,v 1.54 2017/06/29 16:51:35 espie Exp $
+#	$OpenBSD: Makefile.socppc,v 1.55 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -149,7 +149,7 @@ install-kernel-${MACHINE_NAME}:
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/sys/arch/sparc64/conf/Makefile.sparc64 b/sys/arch/sparc64/conf/Makefile.sparc64
index defb1d3d145..d1eb5f8d953 100644
--- a/sys/arch/sparc64/conf/Makefile.sparc64
+++ b/sys/arch/sparc64/conf/Makefile.sparc64
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.sparc64,v 1.91 2017/07/16 16:47:07 visa Exp $
+#	$OpenBSD: Makefile.sparc64,v 1.92 2017/07/18 16:43:27 tb Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -122,8 +122,10 @@ ld.script: ${_machdir}/conf/ld.script
 makegap.sh:
 	cp $S/conf/makegap.sh $@
 
-gap.o:	Makefile makegap.sh
-	LD="${LD}" sh makegap.sh 0x00000000
+MAKE_GAP = LD="${LD}" sh makegap.sh 0x00000000
+
+gap.o:	Makefile makegap.sh vers.o
+	${MAKE_GAP}
 
 vers.o: ${SYSTEM_DEP:Ngap.o}
 	sh $S/conf/newvers.sh
@@ -158,7 +160,7 @@ install: update-link newinstall
  ${SYSTEM_OBJ}: ${DB_STRUCTINFO}
 .endif
 .ifnmake clean
-. for o in ${SYSTEM_OBJ} assym.h ${DB_STRUCTINFO}
+. for o in ${SYSTEM_OBJ:Ngap.o} assym.h ${DB_STRUCTINFO}
 .  if exists(${o:R}.d)
 .   include "${o:R}.d"
 .  elif exists($o)
diff --git a/usr.sbin/config/mkmakefile.c b/usr.sbin/config/mkmakefile.c
index c2ac4c63626..79f59c898ab 100644
--- a/usr.sbin/config/mkmakefile.c
+++ b/usr.sbin/config/mkmakefile.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mkmakefile.c,v 1.43 2017/06/22 15:57:16 deraadt Exp $	*/
+/*	$OpenBSD: mkmakefile.c,v 1.44 2017/07/18 16:43:27 tb Exp $	*/
 /*	$NetBSD: mkmakefile.c,v 1.34 1997/02/02 21:12:36 thorpej Exp $	*/
 
 /*
@@ -510,9 +510,10 @@ emitload(FILE *fp)
 		if (fputs("\t${NORMAL_C}\n\n", fp) < 0)
 			return (1);
 
-		if (fprintf(fp, "new%s: gap.o\n", nm) < 0)
+		if (fprintf(fp, "new%s:\n", nm) < 0)
 			return (1);
 		if (fprintf(fp,
+		    "\t${MAKE_GAP}\n"
 		    "\t${SYSTEM_LD_HEAD}\n"
 		    "\t${SYSTEM_LD} swap%s.o\n"
 		    "\t${SYSTEM_LD_TAIL}\n"