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>
This commit is contained in:
Paul Smith
2006-03-05 17:14:10 -05:00
committed by Sam Ravnborg
parent 7b75b13cda
commit 4f1933620f
25 changed files with 144 additions and 75 deletions

View File

@@ -82,7 +82,7 @@ drivers-$(CONFIG_OPROFILE) += arch/powerpc/oprofile/
BOOT_TARGETS = zImage zImage.initrd znetboot znetboot.initrd vmlinux.sm
.PHONY: $(BOOT_TARGETS)
PHONY += $(BOOT_TARGETS)
all: uImage zImage

View File

@@ -1,6 +1,9 @@
#
# 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 @@ subdir- += simple openfirmware
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)

View File

@@ -1,5 +1,8 @@
# 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 @@ $(images)/zImage.chrp-rs6k $(images)/zImage.initrd.chrp-rs6k: \
# 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 @@ zImage.initrd: $(images)/zImage.initrd.chrp \
TFTPIMAGE := /tftpboot/zImage
.PHONY: znetboot znetboot.initrd
PHONY += znetboot znetboot.initrd
znetboot: $(images)/zImage.chrp
cp $(images)/zImage.chrp $(TFTPIMAGE).chrp$(END)
@echo ' kernel: $@ is ready ($<)'