kbuild: Separate output directory - core patch

From: Sam Ravnborg (sam_at_ravnborg.org)
Date: 08/19/03

  • Next message: Sam Ravnborg: "Re: kbuild: Separate output directory - ieee patch"
    Date:	Tue, 19 Aug 2003 23:51:57 +0200
    To: Linus Torvalds <torvalds@osdl.org>, Andrew Morton <akpm@osdl.org>
    
    

    # 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 sam@mars.ravnborg.org 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)) < $< > $@.tmp; \
             if [ -r $@ ] && cmp -s $@ $@.tmp; then \
                     rm -f $@.tmp; \
    @@ -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
    --- a/scripts/Makefile.build Tue Aug 19 23:40:39 2003
    +++ b/scripts/Makefile.build Tue Aug 19 23:40:39 2003
    @@ -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.lib b/scripts/Makefile.lib
    --- a/scripts/Makefile.lib Tue Aug 19 23:40:39 2003
    +++ b/scripts/Makefile.lib Tue Aug 19 23:40:39 2003
    @@ -58,6 +58,9 @@
     # in the local directory
     subdir-obj-y := $(foreach o,$(obj-y),$(if $(filter-out $(o),$(notdir $(o))),$(o)))
     
    +# $(obj-dirs) is a list of directories that contain object files
    +obj-dirs := $(filter-out ./, $(sort $(dir $(multi-objs) $(subdir-obj-y))))
    +
     # Replace multi-part objects by their individual parts, look at local dir only
     real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)
     real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
    @@ -107,6 +110,7 @@
     multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y))
     multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m))
     subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
    +obj-dirs := $(addprefix $(obj)/,$(obj-dirs))
     host-progs := $(addprefix $(obj)/,$(host-progs))
     host-csingle := $(addprefix $(obj)/,$(host-csingle))
     host-cmulti := $(addprefix $(obj)/,$(host-cmulti))
    @@ -129,15 +133,46 @@
     # where foo and bar are the name of the modules.
     basename_flags = -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F)))
     modname_flags = $(if $(filter 1,$(words $(modname))),-DKBUILD_MODNAME=$(subst $(comma),_,$(subst -,_,$(modname))))
    -c_flags = -Wp,-MD,$(depfile) $(CFLAGS) $(NOSTDINC_FLAGS) \
    - $(modkern_cflags) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o) \
    - $(basename_flags) $(modname_flags)
    -a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(NOSTDINC_FLAGS)\
    - $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
    -hostc_flags = -Wp,-MD,$(depfile) $(HOSTCFLAGS) $(HOST_EXTRACFLAGS)\
    - $(HOSTCFLAGS_$(*F).o)
    -hostcxx_flags = -Wp,-MD,$(depfile) $(HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS)\
    - $(HOSTCXXFLAGS_$(*F).o)
    +
    +
    +_c_flags = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o)
    +_a_flags = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
    +_hostc_flags = $(HOSTCFLAGS) $(HOST_EXTRACFLAGS) $(HOSTCFLAGS_$(*F).o)
    +_hostcxx_flags = $(HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) $(HOSTCXXFLAGS_$(*F).o)
    +
    +
    +# If building the kernel in a separate objtree expand all occurrences
    +# of -Idir to -Idir -I$(srctree)/dir.
    +# hereby allowing gcc to locate files in both trees. Local tree first.
    +
    +ifeq ($(KBUILD_OUTPUT),)
    +__c_flags = $(_c_flags)
    +__a_flags = $(_a_flags)
    +__hostc_flags = $(_hostc_flags)
    +__hostcxx_flags = $(_hostcxx_flags)
    +else
    +flags = $(foreach o,$($(1)),\
    + $(if $(filter -I%,$(o)),$(patsubst -I%,-I$(srctree)/%,$(o)),$(o)))
    +
    +# -I$(obj) locate generated .h files
    +# -I$(srctree)/$(src) locate .h files in srctree, from generated .c files
    +# FIXME: Replace both with specific EXTRA_CFLAGS statements
    +__c_flags = -I$(obj) -I$(srctree)/$(src) $(call flags,_c_flags)
    +__a_flags = $(call flags,_a_flags)
    +__hostc_flags = -I$(obj) $(call flags,_hostc_flags)
    +__hostcxx_flags = $(call flags,_hostcxx_flags)
    +endif
    +
    +c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(CPPFLAGS) \
    + $(__c_flags) $(modkern_cflags) \
    + $(basename_flags) $(modname_flags)
    +
    +a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(CPPFLAGS) \
    + $(__a_flags) $(modkern_aflags)
    +
    +hostc_flags = -Wp,-MD,$(depfile) $(__hostc_flags)
    +hostcxx_flags = -Wp,-MD,$(depfile) $(__hostcxx_flags)
    +
     ld_flags = $(LDFLAGS) $(EXTRA_LDFLAGS)
     
     # Finds the multi-part object the current object will be linked into
    @@ -230,9 +265,9 @@
     # $(call descend,<dir>,<target>)
     # Recursively call a sub-make in <dir> with target <target>
     # Usage is deprecated, because make do not see this as an invocation of make.
    -descend =$(Q)$(MAKE) -f scripts/Makefile.build obj=$(1) $(2)
    +descend =$(Q)$(MAKE) -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.build obj=$(1) $(2)
     
     # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
     # Usage:
     # $(Q)$(MAKE) $(build)=dir
    -build := -f scripts/Makefile.build obj
    +build := -f $(if $(KBUILD_OUTPUT),$(srctree)/)scripts/Makefile.build obj
    diff -Nru a/scripts/Makefile.modpost b/scripts/Makefile.modpost
    --- a/scripts/Makefile.modpost Tue Aug 19 23:40:39 2003
    +++ b/scripts/Makefile.modpost Tue Aug 19 23:40:39 2003
    @@ -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
    -
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  • Next message: Sam Ravnborg: "Re: kbuild: Separate output directory - ieee patch"

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