kbuild: change kbuild to not rely on incorrect GNU make behavior

The kbuild system takes advantage of an incorrect behavior in GNU make. Once this behavior is fixed, all files in the kernel rebuild every time, even if nothing has changed. This patch ensures kbuild works with both the incorrect and correct behaviors of GNU make. For more details on the incorrect behavior, see: http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html Changes in this patch: - Keep all targets that are to be marked .PHONY in a variable, PHONY. - Add .PHONY: $(PHONY) to mark them properly. - Remove any $(PHONY) files from the $? list when determining whether targets are up-to-date or not. Signed-off-by: Paul Smith <psmith@gnu.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

kbuild: change kbuild to not rely on incorrect GNU make behavior
The kbuild system takes advantage of an incorrect behavior in GNU make. Once this behavior is fixed, all files in the kernel rebuild every time, even if nothing has changed. This patch ensures kbuild works with both the incorrect and correct behaviors of GNU make. For more details on the incorrect behavior, see: http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html Changes in this patch: - Keep all targets that are to be marked .PHONY in a variable, PHONY. - Add .PHONY: $(PHONY) to mark them properly. - Remove any $(PHONY) files from the $? list when determining whether targets are up-to-date or not. Signed-off-by: Paul Smith <psmith@gnu.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Paul Smith · Sam Ravnborg
1 parent 7b75b13cda
Showing 25 changed files with 144 additions and 75 deletions Side-by-side Diff
Documentation/DocBook/Makefile
Makefile
arch/arm/Makefile
arch/arm/boot/Makefile
arch/arm/boot/bootp/Makefile
arch/arm26/Makefile
arch/arm26/boot/Makefile
arch/i386/Makefile
arch/ia64/Makefile
arch/m32r/Makefile
arch/powerpc/Makefile
arch/ppc/Makefile
arch/ppc/boot/Makefile
arch/ppc/boot/openfirmware/Makefile
arch/sh/Makefile
arch/um/Makefile
arch/x86_64/Makefile
scripts/Kbuild.include
scripts/Makefile.build
scripts/Makefile.clean
@@ -28,7 +28,7 @@
  
 ###
 # The targets that may be used.
-.PHONY:	xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
+PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
  
 BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
 xmldocs: $(BOOKS)
@@ -211,4 +211,10 @@
  
 #man put files in man subdir - traverse down
 subdir- := man/
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
@@ -95,7 +95,7 @@
 endif
  
 # That's our default target when none is given on the command line
-.PHONY: _all
+PHONY := _all
 _all:
  
 ifneq ($(KBUILD_OUTPUT),)
@@ -106,7 +106,7 @@
 $(if $(KBUILD_OUTPUT),, \
      $(error output directory "$(saved-output)" does not exist))
  
-.PHONY: $(MAKECMDGOALS)
+PHONY += $(MAKECMDGOALS)
  
 $(filter-out _all,$(MAKECMDGOALS)) _all:
 	$(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
@@ -123,7 +123,7 @@
  
 # If building an external module we do not care about the all: rule
 # but instead _all depend on modules
-.PHONY: all
+PHONY += all
 ifeq ($(KBUILD_EXTMOD),)
 _all: all
 else
  
@@ -337,14 +337,14 @@
 # Rules shared between *config targets and build targets
  
 # Basic helpers built in scripts/
-.PHONY: scripts_basic
+PHONY += scripts_basic
 scripts_basic:
 	$(Q)$(MAKE) $(build)=scripts/basic
  
 # To avoid any implicit rule to kick in, define an empty command.
 scripts/basic/%: scripts_basic ;
  
-.PHONY: outputmakefile
+PHONY += outputmakefile
 # outputmakefile generate a Makefile to be placed in output directory, if
 # using a seperate output directory. This allows convinient use
 # of make in output directory
@@ -420,7 +420,7 @@
 # Additional helpers built in scripts/
 # Carefully list dependencies so we do not try to build scripts twice
 # in parrallel
-.PHONY: scripts
+PHONY += scripts
 scripts: scripts_basic include/config/MARKER
 	$(Q)$(MAKE) $(build)=$(@)
  
@@ -720,7 +720,7 @@
 # make menuconfig etc.
 # Error messages still appears in the original language
  
-.PHONY: $(vmlinux-dirs)
+PHONY += $(vmlinux-dirs)
 $(vmlinux-dirs): prepare scripts
 	$(Q)$(MAKE) $(build)=$@
  
  
@@ -773,10 +773,10 @@
 # version.h and scripts_basic is processed / created.
  
 # Listed in dependency order
-.PHONY: prepare archprepare prepare0 prepare1 prepare2 prepare3
+PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
  
 # prepare-all is deprecated, use prepare as valid replacement
-.PHONY: prepare-all
+PHONY += prepare-all
  
 # prepare3 is used to check if we are building in a separate output directory,
 # and if so do:
@@ -857,7 +857,7 @@
  
 # ---------------------------------------------------------------------------
  
-.PHONY: depend dep
+PHONY += depend dep
 depend dep:
 	@echo '*** Warning: make $@ is unnecessary now.'
  
  
  
  
@@ -872,21 +872,21 @@
  
 #	Build modules
  
-.PHONY: modules
+PHONY += modules
 modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
 	@echo '  Building modules, stage 2.';
 	$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
  
  
 # Target to prepare building external modules
-.PHONY: modules_prepare
+PHONY += modules_prepare
 modules_prepare: prepare scripts
  
 # Target to install modules
-.PHONY: modules_install
+PHONY += modules_install
 modules_install: _modinst_ _modinst_post
  
-.PHONY: _modinst_
+PHONY += _modinst_
 _modinst_:
 	@if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
 		echo "Warning: you may need to install module-init-tools"; \
@@ -913,7 +913,7 @@
 else
 depmod_opts	:= -b $(INSTALL_MOD_PATH) -r
 endif
-.PHONY: _modinst_post
+PHONY += _modinst_post
 _modinst_post: _modinst_
 	if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
  
@@ -956,7 +956,7 @@
 clean: rm-files := $(CLEAN_FILES)
 clean-dirs      := $(addprefix _clean_,$(srctree) $(vmlinux-alldirs))
  
-.PHONY: $(clean-dirs) clean archclean
+PHONY += $(clean-dirs) clean archclean
 $(clean-dirs):
 	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
  
@@ -974,7 +974,7 @@
 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
 mrproper-dirs      := $(addprefix _mrproper_,Documentation/DocBook scripts)
  
-.PHONY: $(mrproper-dirs) mrproper archmrproper
+PHONY += $(mrproper-dirs) mrproper archmrproper
 $(mrproper-dirs):
 	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
  
@@ -984,7 +984,7 @@
  
 # distclean
 #
-.PHONY: distclean
+PHONY += distclean
  
 distclean: mrproper
 	@find $(srctree) $(RCS_FIND_IGNORE) \
@@ -1000,7 +1000,7 @@
 # rpm target kept for backward compatibility
 package-dir	:= $(srctree)/scripts/package
  
-.PHONY: %-pkg rpm
+PHONY += %-pkg rpm
  
 %pkg: FORCE
 	$(Q)$(MAKE) -f $(package-dir)/Makefile $@
  
@@ -1092,12 +1092,12 @@
  
 # We are always building modules
 KBUILD_MODULES := 1
-.PHONY: crmodverdir
+PHONY += crmodverdir
 crmodverdir:
 	$(Q)rm -rf $(MODVERDIR)
 	$(Q)mkdir -p $(MODVERDIR)
  
-.PHONY: $(objtree)/Module.symvers
+PHONY += $(objtree)/Module.symvers
 $(objtree)/Module.symvers:
 	@test -e $(objtree)/Module.symvers || ( \
 	echo; \
@@ -1106,7 +1106,7 @@
 	echo )
  
 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
-.PHONY: $(module-dirs) modules
+PHONY += $(module-dirs) modules
 $(module-dirs): crmodverdir $(objtree)/Module.symvers
 	$(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
  
  
@@ -1114,11 +1114,11 @@
 	@echo '  Building modules, stage 2.';
 	$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
  
-.PHONY: modules_install
+PHONY += modules_install
 modules_install: _emodinst_ _emodinst_post
  
-install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)	
-.PHONY: _emodinst_
+install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
+PHONY += _emodinst_
 _emodinst_:
 	$(Q)rm -rf $(MODLIB)/$(install-dir)
 	$(Q)mkdir -p $(MODLIB)/$(install-dir)
  
@@ -1133,13 +1133,13 @@
 		      $(KERNELRELEASE);                       \
                    fi
  
-.PHONY: _emodinst_post
+PHONY += _emodinst_post
 _emodinst_post: _emodinst_
 	$(call cmd,depmod)
  
 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
  
-.PHONY: $(clean-dirs) clean
+PHONY += $(clean-dirs) clean
 $(clean-dirs):
 	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
  
@@ -1161,7 +1161,7 @@
 	@echo  ''
  
 # Dummies...
-.PHONY: prepare scripts
+PHONY += prepare scripts
 prepare: ;
 scripts: ;
 endif # KBUILD_EXTMOD
@@ -1274,7 +1274,7 @@
 endif #ifeq ($(config-targets),1)
 endif #ifeq ($(mixed-targets),1)
  
-.PHONY: checkstack
+PHONY += checkstack
 checkstack:
 	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
 	$(PERL) $(src)/scripts/checkstack.pl $(ARCH)
  
@@ -1357,5 +1357,11 @@
  
 endif	# skip-makefile
  
+PHONY += FORCE
 FORCE:
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+.PHONY: $(PHONY)
 #
 # arch/arm/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -176,7 +179,7 @@
  
 archprepare: maketools
  
-.PHONY: maketools FORCE
+PHONY += maketools FORCE
 maketools: include/linux/version.h include/asm-arm/.arch FORCE
 	$(Q)$(MAKE) $(build)=arch/arm/tools include/asm-arm/mach-types.h
  
 #
 # arch/arm/boot/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -73,7 +76,7 @@
 	$(call if_changed,objcopy)
 	@echo '  Kernel: $@ is ready'
  
-.PHONY: initrd FORCE
+PHONY += initrd FORCE
 initrd:
 	@test "$(INITRD_PHYS)" != "" || \
 	(echo This machine does not support INITRD; exit -1)
 #
 # linux/arch/arm/boot/bootp/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
  
 LDFLAGS_bootp	:=-p --no-undefined -X \
 		 --defsym initrd_phys=$(INITRD_PHYS) \
@@ -21,5 +24,5 @@
  
 $(obj)/initrd.o: $(INITRD) FORCE
  
-.PHONY:	$(INITRD) FORCE
+PHONY += $(INITRD) FORCE
 #
 # arch/arm26/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
  
@@ -49,9 +52,9 @@
  
 boot := arch/arm26/boot
  
-.PHONY: maketools FORCE
+PHONY += maketools FORCE
 maketools: FORCE
-	
+
  
 # Convert bzImage to zImage
 bzImage: vmlinux
 #
 # arch/arm26/boot/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -60,7 +63,7 @@
 	@echo '  Kernel: $@ is ready'
 endif
  
-.PHONY: initrd
+PHONY += initrd
 initrd:
 	@test "$(INITRD_PHYS)" != "" || \
 	(echo This machine does not support INITRD; exit -1)
@@ -99,8 +99,8 @@
  
 boot := arch/i386/boot
  
-.PHONY: zImage bzImage compressed zlilo bzlilo \
-	zdisk bzdisk fdimage fdimage144 fdimage288 install
+PHONY += zImage bzImage compressed zlilo bzlilo \
+         zdisk bzdisk fdimage fdimage144 fdimage288 install
  
 all: bzImage
  
 #
 # ia64/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -62,7 +65,7 @@
  
 boot := arch/ia64/hp/sim/boot
  
-.PHONY: boot compressed check
+PHONY += boot compressed check
  
 all: compressed unwcheck
  
 #
 # m32r/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
  
 LDFLAGS		:=
 OBJCOPYFLAGS	:= -O binary -R .note -R .comment -S
@@ -39,7 +42,7 @@
  
 boot := arch/m32r/boot
  
-.PHONY: zImage
+PHONY += zImage
  
 all: zImage
  
@@ -150,7 +150,7 @@
  
 BOOT_TARGETS = zImage zImage.initrd znetboot znetboot.initrd vmlinux.sm uImage
  
-.PHONY: $(BOOT_TARGETS)
+PHONY += $(BOOT_TARGETS)
  
 boot := arch/$(ARCH)/boot
  
@@ -82,7 +82,7 @@
  
 BOOT_TARGETS = zImage zImage.initrd znetboot znetboot.initrd vmlinux.sm
  
-.PHONY: $(BOOT_TARGETS)
+PHONY += $(BOOT_TARGETS)
  
 all: uImage zImage
  
 #
 # arch/ppc/boot/Makefile
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
@@ -25,7 +28,7 @@
  
 hostprogs-y := $(addprefix utils/, addnote mknote hack-coff mkprep mkbugboot mktree)
  
-.PHONY: $(BOOT_TARGETS) $(bootdir-y)
+PHONY += $(BOOT_TARGETS) $(bootdir-y)
  
 $(BOOT_TARGETS): $(bootdir-y)
  
 # Makefile for making bootable images on various OpenFirmware machines.
 #
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # Paul Mackerras	January 1997
 #	XCOFF bootable images for PowerMacs
 # Geert Uytterhoeven	September 1997
@@ -86,7 +89,7 @@
  
 # The targets used on the make command-line
  
-.PHONY: zImage zImage.initrd
+PHONY += zImage zImage.initrd
 zImage:		 $(images)/zImage.chrp		\
 		 $(images)/zImage.chrp-rs6k
 	@echo '  kernel: $@ is ready ($<)'
@@ -96,7 +99,7 @@
  
 TFTPIMAGE	:= /tftpboot/zImage
  
-.PHONY: znetboot znetboot.initrd
+PHONY += znetboot znetboot.initrd
 znetboot:	$(images)/zImage.chrp
 	cp $(images)/zImage.chrp      $(TFTPIMAGE).chrp$(END)
 	@echo '  kernel: $@ is ready ($<)'
@@ -172,7 +172,7 @@
  
 archprepare: maketools include/asm-sh/.cpu include/asm-sh/.mach
  
-.PHONY: maketools FORCE
+PHONY += maketools FORCE
 maketools:  include/linux/version.h FORCE
 	$(Q)$(MAKE) $(build)=arch/sh/tools include/asm-sh/machtypes.h
  
-# 
+#
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
 # Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
 # Licensed under the GPL
 #
@@ -88,7 +91,7 @@
  
 SIZE = (($(CONFIG_NEST_LEVEL) + $(CONFIG_KERNEL_HALF_GIGS)) * 0x20000000)
  
-.PHONY: linux
+PHONY += linux
  
 all: linux
  
@@ -67,8 +67,8 @@
  
 boot := arch/x86_64/boot
  
-.PHONY: bzImage bzlilo install archmrproper \
-	fdimage fdimage144 fdimage288 archclean
+PHONY += bzImage bzlilo install archmrproper \
+	 fdimage fdimage144 fdimage288 archclean
  
 #Default target when executing "make"
 all: bzImage
@@ -116,16 +116,18 @@
 # function to only execute the passed command if necessary
 # >'< substitution is for echo to work, >$< substitution to preserve $ when reloading .cmd file
 # note: when using inline perl scripts [perl -e '...$$t=1;...'] in $(cmd_xxx) double $$ your perl vars
-# 
-if_changed = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \
+#
+if_changed = $(if $(strip $(filter-out $(PHONY),$?)          \
+		$(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \
 	@set -e; \
 	$(echo-cmd) $(cmd_$(1)); \
 	echo 'cmd_$@ := $(make-cmd)' > $(@D)/.$(@F).cmd)
  
 # execute the command and also postprocess generated .d dependencies
 # file
-if_changed_dep = $(if $(strip $? $(filter-out FORCE $(wildcard $^),$^)\
-	$(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),                  \
+if_changed_dep = $(if $(strip $(filter-out $(PHONY),$?)  \
+		$(filter-out FORCE $(wildcard $^),$^)    \
+	$(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),     \
 	@set -e; \
 	$(echo-cmd) $(cmd_$(1)); \
 	scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(@D)/.$(@F).tmp; \
@@ -135,7 +137,8 @@
 # Usage: $(call if_changed_rule,foo)
 # will check if $(cmd_foo) changed, or any of the prequisites changed,
 # and if so will execute $(rule_foo)
-if_changed_rule = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),\
+if_changed_rule = $(if $(strip $(filter-out $(PHONY),$?)            \
+			$(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),\
 			@set -e; \
 			$(rule_$(1)))
@@ -4,7 +4,7 @@
  
 src := $(obj)
  
-.PHONY: __build
+PHONY := __build
 __build:
  
 # Read .config if it exist, otherwise ignore
  
@@ -308,14 +308,14 @@
 # Descending
 # ---------------------------------------------------------------------------
  
-.PHONY: $(subdir-ym)
+PHONY += $(subdir-ym)
 $(subdir-ym):
 	$(Q)$(MAKE) $(build)=$@
  
 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 # ---------------------------------------------------------------------------
  
-.PHONY: FORCE
+PHONY += FORCE
  
 FORCE:
  
@@ -330,4 +330,10 @@
 ifneq ($(cmd_files),)
   include $(cmd_files)
 endif
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
@@ -4,7 +4,7 @@
  
 src := $(obj)
  
-.PHONY: __clean
+PHONY := __clean
 __clean:
  
 # Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
  
@@ -87,11 +87,17 @@
 # Descending
 # ---------------------------------------------------------------------------
  
-.PHONY: $(subdir-ymn)
+PHONY += $(subdir-ymn)
 $(subdir-ymn):
 	$(Q)$(MAKE) $(clean)=$@
  
 # If quiet is set, only print short version of command
  
 cmd = @$(if $($(quiet)cmd_$(1)),echo '  $($(quiet)cmd_$(1))' &&) $(cmd_$(1))
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
@@ -2,7 +2,7 @@
 # Installing modules
 # ==========================================================================
  
-.PHONY: __modinst
+PHONY := __modinst
 __modinst:
  
 include scripts/Kbuild.include
@@ -12,7 +12,7 @@
 __modules := $(sort $(shell grep -h '\.ko' /dev/null $(wildcard $(MODVERDIR)/*.mod)))
 modules := $(patsubst %.o,%.ko,$(wildcard $(__modules:.ko=.o)))
  
-.PHONY: $(modules)
+PHONY += $(modules)
 __modinst: $(modules)
 	@:
  
@@ -27,4 +27,10 @@
  
 $(modules):
 	$(call cmd,modules_install,$(MODLIB)/$(modinst_dir))
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
@@ -32,7 +32,7 @@
 # Step 4 is solely used to allow module versioning in external modules,
 # where the CRC of each module is retrieved from the Module.symers file.
  
-.PHONY: _modpost
+PHONY := _modpost
 _modpost: __modpost
  
 include .config
@@ -60,7 +60,7 @@
 	$(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \
 	$(filter-out FORCE,$^)
  
-.PHONY: __modpost
+PHONY += __modpost
 __modpost: $(wildcard vmlinux) $(modules:.ko=.o) FORCE
 	$(call cmd,modpost)
  
@@ -97,7 +97,7 @@
 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 # ---------------------------------------------------------------------------
  
-.PHONY: FORCE
+PHONY += FORCE
  
 FORCE:
  
@@ -112,4 +112,10 @@
 ifneq ($(cmd_files),)
   include $(cmd_files)
 endif
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
@@ -2,7 +2,7 @@
 # Kernel configuration targets
 # These targets are used from top-level makefile
  
-.PHONY: oldconfig xconfig gconfig menuconfig config silentoldconfig update-po-config
+PHONY += oldconfig xconfig gconfig menuconfig config silentoldconfig update-po-config
  
 xconfig: $(obj)/qconf
 	$< arch/$(ARCH)/Kconfig
@@ -42,7 +42,7 @@
 	$(Q)rm -f arch/um/Kconfig_arch
 	$(Q)rm -f scripts/kconfig/linux_*.pot scripts/kconfig/config.pot
  
-.PHONY: randconfig allyesconfig allnoconfig allmodconfig defconfig
+PHONY += randconfig allyesconfig allnoconfig allmodconfig defconfig
  
 randconfig: $(obj)/conf
 	$< -r arch/$(ARCH)/Kconfig
@@ -7,10 +7,10 @@
 # we really need to do so. (Do not call gcc as part of make mrproper)
 HOST_EXTRACFLAGS = $(shell $(CONFIG_SHELL) $(check-lxdialog) -ccflags)
 HOST_LOADLIBES   = $(shell $(CONFIG_SHELL) $(check-lxdialog) -ldflags $(HOSTCC))
- 
-HOST_EXTRACFLAGS += -DLOCALE 
  
-.PHONY: dochecklxdialog
+HOST_EXTRACFLAGS += -DLOCALE
+
+PHONY += dochecklxdialog
 $(obj)/dochecklxdialog:
 	$(Q)$(CONFIG_SHELL) $(check-lxdialog) -check $(HOSTCC) $(HOST_LOADLIBES)
  
@@ -32,7 +32,7 @@
 PREV       := set -e; cd ..;
  
 # rpm-pkg
-.PHONY: rpm-pkg rpm
+PHONY += rpm-pkg rpm
  
 $(objtree)/kernel.spec: $(MKSPEC) $(srctree)/Makefile
 	$(CONFIG_SHELL) $(MKSPEC) > $@
  
@@ -54,10 +54,10 @@
 clean-files := $(objtree)/kernel.spec
  
 # binrpm-pkg
-.PHONY: binrpm-pkg
+PHONY += binrpm-pkg
 $(objtree)/binkernel.spec: $(MKSPEC) $(srctree)/Makefile
 	$(CONFIG_SHELL) $(MKSPEC) prebuilt > $@
-	
+
 binrpm-pkg: $(objtree)/binkernel.spec
 	$(MAKE) KBUILD_SRC=
 	set -e; \
@@ -72,7 +72,7 @@
 # Deb target
 # ---------------------------------------------------------------------------
 #
-.PHONY: deb-pkg
+PHONY += deb-pkg
 deb-pkg:
 	$(MAKE) KBUILD_SRC=
 	$(CONFIG_SHELL) $(srctree)/scripts/package/builddeb
@@ -82,7 +82,7 @@
  
 # tarball targets
 # ---------------------------------------------------------------------------
-.PHONY: tar%pkg
+PHONY += tar%pkg
 tar%pkg:
 	$(MAKE) KBUILD_SRC=
 	$(CONFIG_SHELL) $(srctree)/scripts/package/buildtar $@
...	...	@@ -28,7 +28,7 @@
28	28
29	29	###
30	30	# The targets that may be used.
31		-.PHONY: xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
	31	+PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
32	32
33	33	BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
34	34	xmldocs: $(BOOKS)
...	...	@@ -211,4 +211,10 @@
211	211
212	212	#man put files in man subdir - traverse down
213	213	subdir- := man/
	214	+
	215	+
	216	+# Declare the contents of the .PHONY variable as phony. We keep that
	217	+# information in a variable se we can use it in if_changed and friends.
	218	+
	219	+.PHONY: $(PHONY)
...	...	@@ -95,7 +95,7 @@
95	95	endif
96	96
97	97	# That's our default target when none is given on the command line
98		-.PHONY: _all
	98	+PHONY := _all
99	99	_all:
100	100
101	101	ifneq ($(KBUILD_OUTPUT),)
...	...	@@ -106,7 +106,7 @@
106	106	$(if $(KBUILD_OUTPUT),, \
107	107	$(error output directory "$(saved-output)" does not exist))
108	108
109		-.PHONY: $(MAKECMDGOALS)
	109	+PHONY += $(MAKECMDGOALS)
110	110
111	111	$(filter-out _all,$(MAKECMDGOALS)) _all:
112	112	$(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
...	...	@@ -123,7 +123,7 @@
123	123
124	124	# If building an external module we do not care about the all: rule
125	125	# but instead _all depend on modules
126		-.PHONY: all
	126	+PHONY += all
127	127	ifeq ($(KBUILD_EXTMOD),)
128	128	_all: all
129	129	else
130	130
...	...	@@ -337,14 +337,14 @@
337	337	# Rules shared between *config targets and build targets
338	338
339	339	# Basic helpers built in scripts/
340		-.PHONY: scripts_basic
	340	+PHONY += scripts_basic
341	341	scripts_basic:
342	342	$(Q)$(MAKE) $(build)=scripts/basic
343	343
344	344	# To avoid any implicit rule to kick in, define an empty command.
345	345	scripts/basic/%: scripts_basic ;
346	346
347		-.PHONY: outputmakefile
	347	+PHONY += outputmakefile
348	348	# outputmakefile generate a Makefile to be placed in output directory, if
349	349	# using a seperate output directory. This allows convinient use
350	350	# of make in output directory
...	...	@@ -420,7 +420,7 @@
420	420	# Additional helpers built in scripts/
421	421	# Carefully list dependencies so we do not try to build scripts twice
422	422	# in parrallel
423		-.PHONY: scripts
	423	+PHONY += scripts
424	424	scripts: scripts_basic include/config/MARKER
425	425	$(Q)$(MAKE) $(build)=$(@)
426	426
...	...	@@ -720,7 +720,7 @@
720	720	# make menuconfig etc.
721	721	# Error messages still appears in the original language
722	722
723		-.PHONY: $(vmlinux-dirs)
	723	+PHONY += $(vmlinux-dirs)
724	724	$(vmlinux-dirs): prepare scripts
725	725	$(Q)$(MAKE) $(build)=$@
726	726
727	727
...	...	@@ -773,10 +773,10 @@
773	773	# version.h and scripts_basic is processed / created.
774	774
775	775	# Listed in dependency order
776		-.PHONY: prepare archprepare prepare0 prepare1 prepare2 prepare3
	776	+PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
777	777
778	778	# prepare-all is deprecated, use prepare as valid replacement
779		-.PHONY: prepare-all
	779	+PHONY += prepare-all
780	780
781	781	# prepare3 is used to check if we are building in a separate output directory,
782	782	# and if so do:
...	...	@@ -857,7 +857,7 @@
857	857
858	858	# ---------------------------------------------------------------------------
859	859
860		-.PHONY: depend dep
	860	+PHONY += depend dep
861	861	depend dep:
862	862	@echo '*** Warning: make $@ is unnecessary now.'
863	863
864	864
865	865
866	866
...	...	@@ -872,21 +872,21 @@
872	872
873	873	# Build modules
874	874
875		-.PHONY: modules
	875	+PHONY += modules
876	876	modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux)
877	877	@echo ' Building modules, stage 2.';
878	878	$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
879	879
880	880
881	881	# Target to prepare building external modules
882		-.PHONY: modules_prepare
	882	+PHONY += modules_prepare
883	883	modules_prepare: prepare scripts
884	884
885	885	# Target to install modules
886		-.PHONY: modules_install
	886	+PHONY += modules_install
887	887	modules_install: _modinst_ _modinst_post
888	888
889		-.PHONY: _modinst_
	889	+PHONY += _modinst_
890	890	_modinst_:
891	891	@if [ -z "`$(DEPMOD) -V 2>/dev/null \| grep module-init-tools`" ]; then \
892	892	echo "Warning: you may need to install module-init-tools"; \
...	...	@@ -913,7 +913,7 @@
913	913	else
914	914	depmod_opts := -b $(INSTALL_MOD_PATH) -r
915	915	endif
916		-.PHONY: _modinst_post
	916	+PHONY += _modinst_post
917	917	_modinst_post: _modinst_
918	918	if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
919	919
...	...	@@ -956,7 +956,7 @@
956	956	clean: rm-files := $(CLEAN_FILES)
957	957	clean-dirs := $(addprefix _clean_,$(srctree) $(vmlinux-alldirs))
958	958
959		-.PHONY: $(clean-dirs) clean archclean
	959	+PHONY += $(clean-dirs) clean archclean
960	960	$(clean-dirs):
961	961	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
962	962
...	...	@@ -974,7 +974,7 @@
974	974	mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
975	975	mrproper-dirs := $(addprefix _mrproper_,Documentation/DocBook scripts)
976	976
977		-.PHONY: $(mrproper-dirs) mrproper archmrproper
	977	+PHONY += $(mrproper-dirs) mrproper archmrproper
978	978	$(mrproper-dirs):
979	979	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
980	980
...	...	@@ -984,7 +984,7 @@
984	984
985	985	# distclean
986	986	#
987		-.PHONY: distclean
	987	+PHONY += distclean
988	988
989	989	distclean: mrproper
990	990	@find $(srctree) $(RCS_FIND_IGNORE) \
...	...	@@ -1000,7 +1000,7 @@
1000	1000	# rpm target kept for backward compatibility
1001	1001	package-dir := $(srctree)/scripts/package
1002	1002
1003		-.PHONY: %-pkg rpm
	1003	+PHONY += %-pkg rpm
1004	1004
1005	1005	%pkg: FORCE
1006	1006	$(Q)$(MAKE) -f $(package-dir)/Makefile $@
1007	1007
...	...	@@ -1092,12 +1092,12 @@
1092	1092
1093	1093	# We are always building modules
1094	1094	KBUILD_MODULES := 1
1095		-.PHONY: crmodverdir
	1095	+PHONY += crmodverdir
1096	1096	crmodverdir:
1097	1097	$(Q)rm -rf $(MODVERDIR)
1098	1098	$(Q)mkdir -p $(MODVERDIR)
1099	1099
1100		-.PHONY: $(objtree)/Module.symvers
	1100	+PHONY += $(objtree)/Module.symvers
1101	1101	$(objtree)/Module.symvers:
1102	1102	@test -e $(objtree)/Module.symvers \|\| ( \
1103	1103	echo; \
...	...	@@ -1106,7 +1106,7 @@
1106	1106	echo )
1107	1107
1108	1108	module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1109		-.PHONY: $(module-dirs) modules
	1109	+PHONY += $(module-dirs) modules
1110	1110	$(module-dirs): crmodverdir $(objtree)/Module.symvers
1111	1111	$(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1112	1112
1113	1113
...	...	@@ -1114,11 +1114,11 @@
1114	1114	@echo ' Building modules, stage 2.';
1115	1115	$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
1116	1116
1117		-.PHONY: modules_install
	1117	+PHONY += modules_install
1118	1118	modules_install: _emodinst_ _emodinst_post
1119	1119
1120		-install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1121		-.PHONY: _emodinst_
	1120	+install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
	1121	+PHONY += _emodinst_
1122	1122	_emodinst_:
1123	1123	$(Q)rm -rf $(MODLIB)/$(install-dir)
1124	1124	$(Q)mkdir -p $(MODLIB)/$(install-dir)
1125	1125
...	...	@@ -1133,13 +1133,13 @@
1133	1133	$(KERNELRELEASE); \
1134	1134	fi
1135	1135
1136		-.PHONY: _emodinst_post
	1136	+PHONY += _emodinst_post
1137	1137	_emodinst_post: _emodinst_
1138	1138	$(call cmd,depmod)
1139	1139
1140	1140	clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1141	1141
1142		-.PHONY: $(clean-dirs) clean
	1142	+PHONY += $(clean-dirs) clean
1143	1143	$(clean-dirs):
1144	1144	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1145	1145
...	...	@@ -1161,7 +1161,7 @@
1161	1161	@echo ''
1162	1162
1163	1163	# Dummies...
1164		-.PHONY: prepare scripts
	1164	+PHONY += prepare scripts
1165	1165	prepare: ;
1166	1166	scripts: ;
1167	1167	endif # KBUILD_EXTMOD
...	...	@@ -1274,7 +1274,7 @@
1274	1274	endif #ifeq ($(config-targets),1)
1275	1275	endif #ifeq ($(mixed-targets),1)
1276	1276
1277		-.PHONY: checkstack
	1277	+PHONY += checkstack
1278	1278	checkstack:
1279	1279	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') \| \
1280	1280	$(PERL) $(src)/scripts/checkstack.pl $(ARCH)
1281	1281
...	...	@@ -1357,5 +1357,11 @@
1357	1357
1358	1358	endif # skip-makefile
1359	1359
	1360	+PHONY += FORCE
1360	1361	FORCE:
	1362	+
	1363	+
	1364	+# Declare the contents of the .PHONY variable as phony. We keep that
	1365	+# information in a variable se we can use it in if_changed and friends.
	1366	+.PHONY: $(PHONY)
1	1	#
2	2	# arch/arm/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7	# This file is subject to the terms and conditions of the GNU General Public
5	8	# License. See the file "COPYING" in the main directory of this archive
6	9	# for more details.
...	...	@@ -176,7 +179,7 @@
176	179
177	180	archprepare: maketools
178	181
179		-.PHONY: maketools FORCE
	182	+PHONY += maketools FORCE
180	183	maketools: include/linux/version.h include/asm-arm/.arch FORCE
181	184	$(Q)$(MAKE) $(build)=arch/arm/tools include/asm-arm/mach-types.h
182	185
1	1	#
2	2	# arch/arm/boot/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7	# This file is subject to the terms and conditions of the GNU General Public
5	8	# License. See the file "COPYING" in the main directory of this archive
6	9	# for more details.
...	...	@@ -73,7 +76,7 @@
73	76	$(call if_changed,objcopy)
74	77	@echo ' Kernel: $@ is ready'
75	78
76		-.PHONY: initrd FORCE
	79	+PHONY += initrd FORCE
77	80	initrd:
78	81	@test "$(INITRD_PHYS)" != "" \|\| \
79	82	(echo This machine does not support INITRD; exit -1)
1	1	#
2	2	# linux/arch/arm/boot/bootp/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7
5	8	LDFLAGS_bootp :=-p --no-undefined -X \
6	9	--defsym initrd_phys=$(INITRD_PHYS) \
...	...	@@ -21,5 +24,5 @@
21	24
22	25	$(obj)/initrd.o: $(INITRD) FORCE
23	26
24		-.PHONY: $(INITRD) FORCE
	27	+PHONY += $(INITRD) FORCE
1	1	#
2	2	# arch/arm26/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7	# This file is subject to the terms and conditions of the GNU General Public
5	8	# License. See the file "COPYING" in the main directory of this archive
6	9	# for more details.
7	10
...	...	@@ -49,9 +52,9 @@
49	52
50	53	boot := arch/arm26/boot
51	54
52		-.PHONY: maketools FORCE
	55	+PHONY += maketools FORCE
53	56	maketools: FORCE
54		-
	57	+
55	58
56	59	# Convert bzImage to zImage
57	60	bzImage: vmlinux
1	1	#
2	2	# arch/arm26/boot/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7	# This file is subject to the terms and conditions of the GNU General Public
5	8	# License. See the file "COPYING" in the main directory of this archive
6	9	# for more details.
...	...	@@ -60,7 +63,7 @@
60	63	@echo ' Kernel: $@ is ready'
61	64	endif
62	65
63		-.PHONY: initrd
	66	+PHONY += initrd
64	67	initrd:
65	68	@test "$(INITRD_PHYS)" != "" \|\| \
66	69	(echo This machine does not support INITRD; exit -1)
...	...	@@ -99,8 +99,8 @@
99	99
100	100	boot := arch/i386/boot
101	101
102		-.PHONY: zImage bzImage compressed zlilo bzlilo \
103		- zdisk bzdisk fdimage fdimage144 fdimage288 install
	102	+PHONY += zImage bzImage compressed zlilo bzlilo \
	103	+ zdisk bzdisk fdimage fdimage144 fdimage288 install
104	104
105	105	all: bzImage
106	106
1	1	#
2	2	# ia64/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7	# This file is subject to the terms and conditions of the GNU General Public
5	8	# License. See the file "COPYING" in the main directory of this archive
6	9	# for more details.
...	...	@@ -62,7 +65,7 @@
62	65
63	66	boot := arch/ia64/hp/sim/boot
64	67
65		-.PHONY: boot compressed check
	68	+PHONY += boot compressed check
66	69
67	70	all: compressed unwcheck
68	71
1	1	#
2	2	# m32r/Makefile
3	3	#
	4	+# This file is included by the global makefile so that you can add your own
	5	+# architecture-specific flags and dependencies.
	6	+#
4	7
5	8	LDFLAGS :=
6	9	OBJCOPYFLAGS := -O binary -R .note -R .comment -S
...	...	@@ -39,7 +42,7 @@
39	42
40	43	boot := arch/m32r/boot
41	44
42		-.PHONY: zImage
	45	+PHONY += zImage
43	46
44	47	all: zImage
45	48