kbuild: Separate output directory - core patch

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1269 -> 1.1270
# scripts/Makefile.lib 1.20 -> 1.21
# scripts/Makefile.modpost 1.4 -> 1.5
# Makefile 1.421 -> 1.422
# scripts/Makefile.build 1.39 -> 1.40
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/08/19 [email protected] 1.1270
# kbuild: Separate output directory
#
# Enable the possibility to build a kernel in a separate output

# directory. This is useful when dealing with several kernel configurations
# based on the same src, or if you do not want to mix source code
# and output files.
# 
# Usage is simple:
# make O=dir/to/kernel/src {usual make targets}
# 
# This patch implements the core part of separate output directory
# --------------------------------------------
#
diff -Nru a/Makefile b/Makefile
--- a/Makefile	Tue Aug 19 23:40:39 2003
+++ b/Makefile	Tue Aug 19 23:40:39 2003
@@ -9,6 +9,9 @@
 # Comments in this file are targeted only to the developer, do not
 # expect to learn how to build the kernel reading this file.

+# Do not print "Entering directory ..."
+MAKEFLAGS += --no-print-directory
+
# We are using a recursive build, so we need to do a little thinking

 # to get the ordering right.
 #
@@ -25,6 +28,85 @@
 # descending is started. They are now explicitly listed as the
 # prepare rule.

+# To put more focus on warnings, be less verbose as default
+# Use 'make V=1' to see the full commands
+
+ifdef V
+ ifeq ("$(origin V)", "command line")
+ KBUILD_VERBOSE = $(V)
+ endif
+endif
+ifndef KBUILD_VERBOSE
+ KBUILD_VERBOSE = 0
+endif
+
+# Call sparse as part of compilation of C files
+# Use 'make C=1' to enable sparse checking
+
+ifdef C
+ ifeq ("$(origin C)", "command line")
+ KBUILD_CHECKSRC = $(C)
+ endif
+endif
+ifndef KBUILD_CHECKSRC
+ KBUILD_CHECKSRC = 0
+endif
+
+# kbuild support locating output files in a separate directory. +# To locate output files in a separate directory two syntax'es are supported. +# In both cases the working directory must be the root of the kernel src. +# 1) O=
+# Use "make O=dir/to/store/output/files/"
+#
+# 2) Set KBUILD_OBJ
+# Set the environment variable KBUILD_OBJ to point to the directory +# where the output files shall be placed.
+# export KBUILD_OBJ=dir/to/store/output/files/
+# make
+#
+# The O= assigment takes precedence over the KBUILD_OBJ environment variable. +
+# KBUILD_OUTPUT is set on invocation of make in OBJ directory +ifeq ($(KBUILD_OUTPUT),)
+
+# OK, Make called in directory where kernel src resides
+# Do we want to locate output files in a separate directory? +ifdef O
+ ifeq ("$(origin O)", "command line")
+ KBUILD_OBJ := $(O)
+ endif
+endif
+
+# Invoke a second make in the output directory, passing relevant variables +ifneq ($(KBUILD_OBJ),)
+ KBUILD_OBJ := $(shell cd $(KBUILD_OBJ); /bin/pwd)
+%:
+ @$(MAKE) -C $(KBUILD_OBJ) \
+ KBUILD_OUTPUT=1 \
+ KBUILD_SRC=$(CURDIR) \
+ KBUILD_VERBOSE=$(KBUILD_VERBOSE) \
+ KBUILD_CHECK=$(KBUILD_CHECK) \
+ -f $(CURDIR)/Makefile $(MAKECMDGOALS)
+
+# Leave processing to above invocation of make
+skip-makefile := 1
+endif # ifneq ($(KBUILD_OBJ),)
+endif # ifeq ($(KBUILD_OUTPUT),)
+
+# We process the rest of the Makefile if this is the final invocation of make +ifeq ($(skip-makefile),)
+
+srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),.)
+TOPDIR := $(srctree)
+# FIXME - TOPDIR is obsolete, use srctree/objtree
+objtree := $(CURDIR)
+src := $(srctree)
+obj := $(objtree)
+
+VPATH := $(srctree)
+
+export srctree objtree VPATH TOPDIR
+
KERNELRELEASE=$(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)

# SUBARCH tells the usermode build what the underlying arch is. That is set
@@ -69,7 +151,6 @@
CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
else if [ -x /bin/bash ]; then echo /bin/bash; \
else echo sh; fi ; fi)
-TOPDIR := $(CURDIR)

HOSTCC = gcc
HOSTCXX = g++
@@ -110,40 +191,8 @@
KBUILD_MODULES := 1
endif

-export KBUILD_MODULES KBUILD_BUILTIN KBUILD_VERBOSE KBUILD_CHECKSRC -
-# To put more focus on warnings, less verbose as default -# Use 'make V=1' to see the full commands
-
-ifdef V
- ifeq ("$(origin V)", "command line")
- KBUILD_VERBOSE = $(V)
- endif
-endif
-ifndef KBUILD_VERBOSE
- KBUILD_VERBOSE = 0
-endif
-
-# Call sparse as part of compilation of C files
-# Use 'make C=1' to enable sparse checking
-
-ifdef C
- ifeq ("$(origin C)", "command line")
- KBUILD_CHECKSRC = $(C)
- endif
-endif
-ifndef KBUILD_CHECKSRC
- KBUILD_CHECKSRC = 0
-endif
-
-# Do not print 'Entering directory ...'
-
-MAKEFLAGS += --no-print-directory
-
-# For maximum performance (+ possibly random breakage, uncomment -# the following)
-
-#MAKEFLAGS += -rR
+export KBUILD_MODULES KBUILD_BUILTIN KBUILD_VERBOSE +export KBUILD_CHECKSRC KBUILD_OUTPUT

# Beautify output
# ---------------------------------------------------------------------------
@@ -185,14 +234,13 @@

export quiet Q KBUILD_VERBOSE

-# Paths to obj / src tree
+# Look for make include files relative to root of kernel src +MAKEFLAGS += --include-dir=$(srctree)

-src := .
-obj := .
-srctree := .
-objtree := .
+# For maximum performance (+ possibly random breakage, uncomment +# the following)

-export srctree objtree
+#MAKEFLAGS += -rR

# Make variables (CC, etc...)

@@ -222,13 +270,15 @@

NOSTDINC_FLAGS = -nostdinc -iwithprefix include

-CPPFLAGS := -D__KERNEL__ -Iinclude
+CPPFLAGS := -D__KERNEL__ -Iinclude \
+ $(if $(KBUILD_OUTPUT),-Iinclude2 -I$(srctree)/include)
+
CFLAGS := -Wall -Wstrict-prototypes -Wno-trigraphs -O2 \
-fno-strict-aliasing -fno-common
AFLAGS := -D__ASSEMBLY__

export VERSION PATCHLEVEL SUBLEVEL EXTRAVERSION KERNELRELEASE ARCH \
- CONFIG_SHELL TOPDIR HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
+ CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE \
HOSTCXX HOSTCXXFLAGS LDFLAGS_BLOB LDFLAGS_MODULE CHECK

@@ -283,7 +333,7 @@
# Handle them one by one.

%:: FORCE
- $(Q)$(MAKE) $@
+ $(Q)$(MAKE) -C $(srctree) KBUILD_OUTPUT= $@

else
ifeq ($(config-targets),1)
@@ -311,7 +361,7 @@

-include .config

-include arch/$(ARCH)/Makefile
+include $(srctree)/arch/$(ARCH)/Makefile

# Let architecture Makefiles change CPPFLAGS if needed CFLAGS += $(CPPFLAGS) $(CFLAGS)
@@ -465,14 +515,34 @@
# Handle descending into subdirectories listed in $(SUBDIRS)

.PHONY: $(SUBDIRS)
-$(SUBDIRS): prepare
+$(SUBDIRS): prepare-all
$(Q)$(MAKE) $(build)=$@

-# Things we need done before we descend to build or make
-# module versions are listed in "prepare"
+# Things we need to do before we recursively start building the kernel +# or the modules are listed in "prepare-all".
+# A multi level approach is used. prepare1 is updated first, then prepare0. +# prepare-all is the collection point for the prepare targets.
+
+.PHONY: prepare-all prepare prepare0 prepare1
+
+# prepare1 is used to check if we are building in a separate output directory, +# and if so do:
+# 1) Check that make has not been executed in the kernel src $(srctree) +# 2) Create the include2 directory, used for the second asm symlink +
+prepare1:
+ifneq ($(KBUILD_OUTPUT),)
+ @echo ' Using $(srctree) as source for kernel'
+ $(Q)if [ -h $(srctree)/include/asm -o -f $(srctree)/.config ]; then \
+ echo " $(srctree) is not clean, please run 'make mrproper'";\
+ echo " in the '$(srctree)' directory.";\
+ /bin/false; \
+ fi;
+ $(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
+ $(Q)ln -fsn $(srctree)/include/asm-$(ARCH) include2/asm
+endif

-.PHONY: prepare
-prepare: include/linux/version.h include/asm include/config/MARKER +prepare0: prepare1 include/linux/version.h include/asm include/config/MARKER
ifdef KBUILD_MODULES
ifeq ($(origin SUBDIRS),file)
$(Q)rm -rf $(MODVERDIR)
@@ -483,6 +553,9 @@
endif
$(if $(CONFIG_MODULES),$(Q)mkdir -p $(MODVERDIR))

+# All the preparing..
+prepare-all: prepare0 prepare
+
# Leave this as default for preprocessing vmlinux.lds.S, which is now
# done in arch/$(ARCH)/kernel/Makefile

@@ -511,8 +584,9 @@
# before switching between archs anyway.

include/asm:
- @echo ' Making asm->asm-$(ARCH) symlink'
- @ln -s asm-$(ARCH) $@
+ @echo ' SYMLINK $@ -> include/asm-$(ARCH)'
+ $(Q)if [ ! -d include ]; then mkdir -p include; fi;
+ @ln -fsn asm-$(ARCH) $@

# Split autoconf.h into include/linux/config/*

@@ -570,7 +644,7 @@
.PHONY: modules
modules: $(SUBDIRS) $(if $(KBUILD_BUILTIN),vmlinux)
@echo ' Building modules, stage 2.';
- $(Q)$(MAKE) -rR -f scripts/Makefile.modpost
+ $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost

# Install modules

@@ -583,7 +657,7 @@
@rm -f $(MODLIB)/build
@mkdir -p $(MODLIB)/kernel
@ln -s $(TOPDIR) $(MODLIB)/build
- $(Q)$(MAKE) -rR -f scripts/Makefile.modinst
+ $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst

# If System.map exists, run depmod. This deliberately does not have a

 # dependency on System.map since that would run the dependency tree on
@@ -660,7 +734,8 @@
 	$(MODVERDIR) \
 	.tmp_export-objs \
 	include/config \
-	include/linux/modules
+	include/linux/modules \
+	include2

 # clean - Delete all intermediate files
 #
@@ -794,6 +869,7 @@
 		echo '  No architecture specific help defined for $(ARCH)')
 	@echo  ''
 	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
+	@echo  '  make O=dir [targets] Locate all build output files in \'dir\', including .config'
 	@echo  '  make C=1   [targets] Check all c source with checker tool'
 	@echo  ''
 	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
@@ -824,7 +900,8 @@
 # FIXME Should go into a make.lib or something 
 # ===========================================================================

-a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(AFLAGS_KERNEL) $(NOSTDINC_FLAGS) \
+a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(AFLAGS_KERNEL) \
+ $(NOSTDINC_FLAGS) $(CPPFLAGS) \
$(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)

quiet_cmd_as_o_S = AS $@
@@ -882,6 +959,7 @@
define filechk
@set -e; \
echo ' CHK $@'; \
+ mkdir -p $(dir $@); \
$(filechk_$(1)) < $< > [email protected]; \
if [ -r $@ ] && cmp -s $@ [email protected]; then \
rm -f [email protected]; \
@@ -894,16 +972,18 @@
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=dir # Usage:
# $(Q)$(MAKE) $(build)=dir
-build := -f scripts/Makefile.build obj
+build := -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.build obj

# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir # Usage:
# $(Q)$(MAKE) $(clean)=dir
-clean := -f scripts/Makefile.clean obj
+clean := -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.clean obj

# $(call descend,<dir>,<target>)
# Recursively call a sub-make in <dir> with target <target>
# Usage is deprecated, because make does not see this as an invocation of make.
-descend =$(Q)$(MAKE) -f scripts/Makefile.build obj=$(1) $(2)
+descend =$(Q)$(MAKE) -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.build obj=$(1) $(2) +
+endif # skip-makefile

FORCE:

diff -Nru a/scripts/Makefile.build b/scripts/Makefile.build
@@ -14,6 +14,16 @@
 
 include scripts/Makefile.lib
 
+ifneq ($(KBUILD_OUTPUT),)
+# Create output directory if not already present
+_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
+
+# Create directories for object files if directory does not exist
+# Needed when obj-y := dir/file.o syntax is used
+_dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
+endif
+
+
 ifdef EXTRA_TARGETS
 $(warning kbuild: $(obj)/Makefile - Usage of EXTRA_TARGETS is obsolete in 2.5. Please fix!)
 endif

diff -Nru a/scripts/Makefile.modpost b/scripts/Makefile.modpost
@@ -35,7 +35,7 @@
 # Compile version info for unresolved symbols
 
 quiet_cmd_cc_o_c = CC      $@
-      cmd_cc_o_c = $(CC) -Wp,-MD,$(depfile) $(CFLAGS) $(CFLAGS_MODULE)	\
+      cmd_cc_o_c = $(CC) $(c_flags) $(CFLAGS_MODULE)	\
 		   -c -o $@ $<
 
 $(modules:.ko=.mod.o): %.mod.o: %.mod.c FORCE

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1272 -> 1.1273
# kernel/Makefile 1.32 -> 1.33
# scripts/genksyms/Makefile 1.3 -> 1.4
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/08/19 [email protected] 1.1273
# kbuild: Fix build with seperate output directory
#
# Build rule for ikconfig updated.
# Include directive for genksyms updated
# --------------------------------------------
#

diff -Nru a/kernel/Makefile b/kernel/Makefile
@@ -20,8 +20,6 @@
 obj-$(CONFIG_COMPAT) += compat.o
 obj-$(CONFIG_IKCONFIG) += configs.o
 
-# files to be removed upon make clean
-clean-files := ikconfig.h
 
 ifneq ($(CONFIG_IA64),y)
 # According to Alan Modra <[email protected]>, the -fno-omit-frame-pointer is

@@ -32,8 +30,13 @@
 CFLAGS_sched.o := $(PROFILING) -fno-omit-frame-pointer
 endif
 
-$(obj)/ikconfig.h: scripts/mkconfigs .config Makefile
-	$(CONFIG_SHELL) scripts/mkconfigs .config Makefile > $(obj)/ikconfig.h
+quiet_cmd_ikconfig = IKCFG   $@
+      cmd_ikconfig = $(CONFIG_SHELL) $< .config $(srctree)/Makefile > $@
+
+targets := ikconfig.h
+
+$(obj)/ikconfig.h: scripts/mkconfigs .config Makefile FORCE
+	$(call if_changed,ikconfig)
 
 $(obj)/configs.o: $(obj)/ikconfig.h $(obj)/configs.c \
 		include/linux/version.h include/linux/compile.h

diff -Nru a/scripts/genksyms/Makefile b/scripts/genksyms/Makefile
@@ -3,13 +3,14 @@
 always		:= $(host-progs)
 
 genksyms-objs	:= genksyms.o parse.o lex.o
-
-HOSTCFLAGS_parse.o := -Wno-uninitialized
+# -I needed for generated C source (shipped source)
+HOSTCFLAGS_parse.o := -Wno-uninitialized -I$(obj)
 
 # dependencies on generated files need to be listed explicitly
 
 $(obj)/lex.o: $(obj)/parse.h $(obj)/keywords.c
-
+# -I needed for generated C source (shipped source)
+HOSTCFLAGS_lex.o := -I$(obj)
 
 ifdef GENERATE_PARSER
 

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1271 -> 1.1272
# scripts/Makefile.clean 1.12 -> 1.13
# arch/i386/boot/Makefile 1.26 -> 1.27
# scripts/Makefile.lib 1.21 -> 1.22
# (new) -> 1.1 arch/i386/boot/tools/Makefile
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/08/19 [email protected] 1.1272
# kbuild/i386: Fixes for separate output dir
#
# Update i386 makefiles so they support building a kernel in a seperate

# output directory.
# This includes a new syntax for always :=, where a directory
# may be specified
# --------------------------------------------
#
diff -Nru a/arch/i386/boot/Makefile b/arch/i386/boot/Makefile
--- a/arch/i386/boot/Makefile	Tue Aug 19 23:41:17 2003
+++ b/arch/i386/boot/Makefile	Tue Aug 19 23:41:17 2003
@@ -27,9 +27,8 @@

targets := vmlinux.bin bootsect bootsect.o setup setup.o \
zImage bzImage
-subdir- := compressed
-
-host-progs := tools/build
+subdir- := compressed/
+always := tools/

# ---------------------------------------------------------------------------

@@ -44,7 +43,7 @@
$(obj)/vmlinux.bin $(ROOT_DEV) > $@

$(obj)/zImage $(obj)/bzImage: $(obj)/bootsect $(obj)/setup \
- $(obj)/vmlinux.bin $(obj)/tools/build FORCE
+ $(obj)/vmlinux.bin $(obj)/tools/ FORCE
$(call if_changed,image)
@echo 'Kernel: $@ is ready'

@@ -58,8 +57,7 @@
$(call if_changed,ld)

$(obj)/compressed/vmlinux: FORCE
- $(Q)$(MAKE) -f scripts/Makefile.build obj=$(obj)/compressed \
- IMAGE_OFFSET=$(IMAGE_OFFSET) $@
+ $(Q)$(MAKE) $(build)=$(obj)/compressed IMAGE_OFFSET=$(IMAGE_OFFSET) $@

# Set this if you want to pass append arguments to the zdisk/fdimage kernel FDARGS =

diff -Nru a/arch/i386/boot/tools/Makefile b/arch/i386/boot/tools/Makefile
@@ -0,0 +1,2 @@
+host-progs := build
+always     := $(host-progs)

diff -Nru a/scripts/Makefile.clean b/scripts/Makefile.clean
@@ -13,6 +13,7 @@
 # ==========================================================================
 
 __subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
+__subdir-y	+= $(patsubst %/,%,$(filter %/, $(always)))
 subdir-y	+= $(__subdir-y)
 __subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
 subdir-m	+= $(__subdir-m)

@@ -30,8 +31,9 @@
 
 subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))
 __clean-files	:= $(wildcard $(addprefix $(obj)/, \
-		   $(extra-y) $(EXTRA_TARGETS) $(always) $(host-progs) \
-		   $(targets) $(clean-files)))
+		   $(extra-y) $(EXTRA_TARGETS) \
+		   $(filter-out %/, $(always)) \
+		   $(host-progs) $(targets) $(clean-files)))
 
 # ==========================================================================
 

@@ -63,4 +65,4 @@
 # Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
 # Usage:
 # $(Q)$(MAKE) $(clean)=dir
-clean := -f scripts/Makefile.clean obj
+clean := -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.clean obj

diff -Nru a/scripts/Makefile.lib b/scripts/Makefile.lib
@@ -32,6 +32,7 @@
 #   and add the directory to the list of dirs to descend into: $(subdir-m)
 
 __subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
+__subdir-y	+= $(patsubst %/,%,$(filter %/, $(always)))
 subdir-y	+= $(__subdir-y)
 __subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
 subdir-m	+= $(__subdir-m)

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1270 -> 1.1271
# drivers/ieee1394/Makefile 1.19 -> 1.20
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/08/19 [email protected] 1.1271
# ieee/kbuild: fix oui2c build rule
#
# 1) Refer to script in $(srctree), so separate output directory

# works with this Makefile
# 2) Add oui.c to targets, so kbuild will detect changes in command line - done by 'if_changed'
# 3) Add FORCE to prerequisites to make sure command-line is checked
# --------------------------------------------
#
diff -Nru a/drivers/ieee1394/Makefile b/drivers/ieee1394/Makefile
--- a/drivers/ieee1394/Makefile	Tue Aug 19 23:40:56 2003
+++ b/drivers/ieee1394/Makefile	Tue Aug 19 23:40:56 2003
@@ -16,11 +16,10 @@
 obj-$(CONFIG_IEEE1394_AMDTP) += amdtp.o
 obj-$(CONFIG_IEEE1394_CMP) += cmp.o

-clean-files := oui.c
-
quiet_cmd_oui2c = OUI2C $@
- cmd_oui2c = $(CONFIG_SHELL) $(obj)/oui2c.sh < $(obj)/oui.db > $@
+ cmd_oui2c = $(CONFIG_SHELL) $(srctree)/$(src)/oui2c.sh < $< > $@

-$(obj)/oui.o: $(obj)/oui.c
-$(obj)/oui.c: $(obj)/oui.db $(obj)/oui2c.sh +targets := oui.c
+$(obj)/oui.o: $(src)/oui.c
+$(obj)/oui.c: $(src)/oui.db $(src)/oui2c.sh FORCE
$(call if_changed,oui2c)