Merge tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "One of the most remarkable improvements in this cycle is, Kbuild is
  now able to cache the result of shell commands. Some variables are
  expensive to compute, for example, $(call cc-option,...) invokes the
  compiler. It is not efficient to redo this computation every time,
  even when we are not actually building anything. Kbuild creates a
  hidden file ".cache.mk" that contains invoked shell commands and their
  results. The speed-up should be noticeable.

  Summary:

   - Fix arch build issues (hexagon, sh)

   - Clean up various Makefiles and scripts

   - Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles

   - Cache variables that are expensive to compute

   - Improve cc-ldopton and ld-option for Clang

   - Optimize output directory creation"

* tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kbuild: move coccicheck help from scripts/Makefile.help to top Makefile
  sh: decompressor: add shipped files to .gitignore
  frv: .gitignore: ignore vmlinux.lds
  selinux: remove unnecessary assignment to subdir-
  kbuild: specify FORCE in Makefile.headersinst as .PHONY target
  kbuild: remove redundant mkdir from ./Kbuild
  kbuild: optimize object directory creation for incremental build
  kbuild: create object directories simpler and faster
  kbuild: filter-out PHONY targets from "targets"
  kbuild: remove redundant $(wildcard ...) for cmd_files calculation
  kbuild: create directory for make cache only when necessary
  sh: select KBUILD_DEFCONFIG depending on ARCH
  kbuild: fix linker feature test macros when cross compiling with Clang
  kbuild: shrink .cache.mk when it exceeds 1000 lines
  kbuild: do not call cc-option before KBUILD_CFLAGS initialization
  kbuild: Cache a few more calls to the compiler
  kbuild: Add a cache for generated variables
  kbuild: add forward declaration of default target to Makefile.asm-generic
  kbuild: remove KBUILD_SUBDIR_ASFLAGS and KBUILD_SUBDIR_CCFLAGS
  hexagon/kbuild: replace CFLAGS_MODULE with KBUILD_CFLAGS_MODULE
  ...

Kbuild

@@ -18,7 +18,6 @@ targets := kernel/bounds.s
 
 # We use internal kbuild rules to avoid the "is up to date" message from make
 kernel/bounds.s: kernel/bounds.c FORCE
-	$(Q)mkdir -p $(dir $@)
 	$(call if_changed_dep,cc_s_c)
 
 $(obj)/$(bounds-file): kernel/bounds.s FORCE
@@ -54,7 +53,6 @@ targets += arch/$(SRCARCH)/kernel/asm-offsets.s
 # We use internal kbuild rules to avoid the "is up to date" message from make
 arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
                                       $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
-	$(Q)mkdir -p $(dir $@)
 	$(call if_changed_dep,cc_s_c)
 
 $(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE

arch/arm/Makefile

@@ -16,11 +16,11 @@ LDFLAGS		:=
 LDFLAGS_vmlinux	:=-p --no-undefined -X --pic-veneer
 ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 LDFLAGS_vmlinux	+= --be8
-LDFLAGS_MODULE	+= --be8
+KBUILD_LDFLAGS_MODULE	+= --be8
 endif
 
 ifeq ($(CONFIG_ARM_MODULE_PLTS),y)
-LDFLAGS_MODULE	+= -T $(srctree)/arch/arm/kernel/module.lds
+KBUILD_LDFLAGS_MODULE	+= -T $(srctree)/arch/arm/kernel/module.lds
 endif
 
 GZFLAGS		:=-9
@@ -122,7 +122,7 @@ CFLAGS_ISA	:=-mthumb $(AFLAGS_AUTOIT) $(AFLAGS_NOWARN)
 AFLAGS_ISA	:=$(CFLAGS_ISA) -Wa$(comma)-mthumb
 # Work around buggy relocation from gas if requested:
 ifeq ($(CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11),y)
-CFLAGS_MODULE	+=-fno-optimize-sibling-calls
+KBUILD_CFLAGS_MODULE	+=-fno-optimize-sibling-calls
 endif
 else
 CFLAGS_ISA	:=$(call cc-option,-marm,)

arch/c6x/Makefile

@@ -12,7 +12,7 @@ cflags-y += -mno-dsbt -msdata=none -D__linux__
 
 cflags-$(CONFIG_C6X_BIG_KERNEL) += -mlong-calls
 
-CFLAGS_MODULE   += -mlong-calls -mno-dsbt -msdata=none
+KBUILD_CFLAGS_MODULE   += -mlong-calls -mno-dsbt -msdata=none
 
 CHECKFLAGS      +=
 

arch/frv/kernel/.gitignore

+vmlinux.lds

arch/hexagon/Makefile

@@ -12,9 +12,9 @@ KBUILD_CFLAGS += -fno-short-enums
 
 # Modules must use either long-calls, or use pic/plt.
 # Use long-calls for now, it's easier.  And faster.
-# CFLAGS_MODULE += -fPIC
-# LDFLAGS_MODULE += -shared
-CFLAGS_MODULE += -mlong-calls
+# KBUILD_CFLAGS_MODULE += -fPIC
+# KBUILD_LDFLAGS_MODULE += -shared
+KBUILD_CFLAGS_MODULE += -mlong-calls
 
 cflags-y += $(call cc-option,-mv${CONFIG_HEXAGON_ARCH_VERSION})
 aflags-y += $(call cc-option,-mv${CONFIG_HEXAGON_ARCH_VERSION})

arch/hexagon/kernel/ptrace.c

@@ -18,8 +18,6 @@
  * 02110-1301, USA.
  */
 
-#include <generated/compile.h>
-
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/sched/task_stack.h>
@@ -180,7 +178,7 @@ static const struct user_regset hexagon_regsets[] = {
 };
 
 static const struct user_regset_view hexagon_user_view = {
-	.name = UTS_MACHINE,
+	.name = "hexagon",
 	.e_machine = ELF_ARCH,
 	.ei_osabi = ELF_OSABI,
 	.regsets = hexagon_regsets,

arch/sh/Makefile

@@ -15,6 +15,12 @@ ifneq ($(SUBARCH),$(ARCH))
   endif
 endif
 
+ifeq ($(ARCH),sh)
+KBUILD_DEFCONFIG	:= shx3_defconfig
+else
+KBUILD_DEFCONFIG	:= cayman_defconfig
+endif
+
 isa-y					:= any
 isa-$(CONFIG_SH_DSP)			:= sh
 isa-$(CONFIG_CPU_SH2)			:= sh2
@@ -105,14 +111,12 @@ ifdef CONFIG_SUPERH32
 UTS_MACHINE		:= sh
 BITS			:= 32
 LDFLAGS_vmlinux		+= -e _stext
-KBUILD_DEFCONFIG	:= shx3_defconfig
 else
 UTS_MACHINE		:= sh64
 BITS			:= 64
 LDFLAGS_vmlinux		+= --defsym phys_stext=_stext-$(CONFIG_PAGE_OFFSET) \
 			   --defsym phys_stext_shmedia=phys_stext+1 \
 			   -e phys_stext_shmedia
-KBUILD_DEFCONFIG	:= cayman_defconfig
 endif
 
 ifdef CONFIG_CPU_LITTLE_ENDIAN

arch/sh/boot/compressed/.gitignore

+ashiftrt.S
+ashldi3.c
+ashlsi3.S
+ashrsi3.S
+lshrsi3.S
 vmlinux.bin.*

arch/x86/entry/vdso/Makefile

@@ -130,10 +130,6 @@ $(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE
 CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
 VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1
 
-# This makes sure the $(obj) subdirectory exists even though vdso32/
-# is not a kbuild sub-make subdirectory.
-override obj-dirs = $(dir $(obj)) $(obj)/vdso32/
-
 targets += vdso32/vdso32.lds
 targets += vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o
 targets += vdso32/vclock_gettime.o

scripts/Kbuild.include

@@ -8,6 +8,8 @@ squote  := '
 empty   :=
 space   := $(empty) $(empty)
 space_escape := _-_SPACE_-_
+right_paren := )
+left_paren := (
 
 ###
 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
@@ -80,6 +82,71 @@ cc-cross-prefix =  \
 			echo $(c);                                    \
 		fi)))
 
+# Tools for caching Makefile variables that are "expensive" to compute.
+#
+# Here we want to help deal with variables that take a long time to compute
+# by making it easy to store these variables in a cache.
+#
+# The canonical example here is testing for compiler flags.  On a simple system
+# each call to the compiler takes 10 ms, but on a system with a compiler that's
+# called through various wrappers it can take upwards of 100 ms.  If we have
+# 100 calls to the compiler this can take 1 second (on a simple system) or 10
+# seconds (on a complicated system).
+#
+# The "cache" will be in Makefile syntax and can be directly included.
+# Any time we try to reference a variable that's not in the cache we'll
+# calculate it and store it in the cache for next time.
+
+# Include values from last time
+make-cache := $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/,$(if $(obj),$(obj)/)).cache.mk
+$(make-cache): ;
+-include $(make-cache)
+
+cached-data := $(filter __cached_%, $(.VARIABLES))
+
+# If cache exceeds 1000 lines, shrink it down to 500.
+ifneq ($(word 1000,$(cached-data)),)
+$(shell tail -n 500 $(make-cache) > $(make-cache).tmp; \
+	mv $(make-cache).tmp $(make-cache))
+endif
+
+create-cache-dir := $(if $(KBUILD_SRC),$(if $(cache-data),,1))
+
+# Usage: $(call __sanitize-opt,Hello=Hola$(comma)Goodbye Adios)
+#
+# Convert all '$', ')', '(', '\', '=', ' ', ',', ':' to '_'
+__sanitize-opt = $(subst $$,_,$(subst $(right_paren),_,$(subst $(left_paren),_,$(subst \,_,$(subst =,_,$(subst $(space),_,$(subst $(comma),_,$(subst :,_,$(1)))))))))
+
+# Usage:   $(call shell-cached,shell_command)
+# Example: $(call shell-cached,md5sum /usr/bin/gcc)
+#
+# If we've already seen a call to this exact shell command (even in a
+# previous invocation of make!) we'll return the value.  If not, we'll
+# compute it and store the result for future runs.
+#
+# This is a bit of voodoo, but basic explanation is that if the variable
+# was undefined then we'll evaluate the shell command and store the result
+# into the variable.  We'll then store that value in the cache and finally
+# output the value.
+#
+# NOTE: The $$(2) here isn't actually a parameter to __run-and-store.  We
+# happen to know that the caller will have their shell command in $(2) so the
+# result of "call"ing this will produce a reference to that $(2).  The reason
+# for this strangeness is to avoid an extra level of eval (and escaping) of
+# $(2).
+define __run-and-store
+ifeq ($(origin $(1)),undefined)
+  $$(eval $(1) := $$(shell $$(2)))
+ifeq ($(create-cache-dir),1)
+  $$(shell mkdir -p $(dir $(make-cache)))
+  $$(eval create-cache-dir :=)
+endif
+  $$(shell echo '$(1) := $$($(1))' >> $(make-cache))
+endif
+endef
+__shell-cached = $(eval $(call __run-and-store,$(1)))$($(1))
+shell-cached = $(call __shell-cached,__cached_$(call __sanitize-opt,$(1)),$(1))
+
 # output directory for tests below
 TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
 
@@ -87,30 +154,36 @@ TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
 # Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
 # Exit code chooses option. "$$TMP" serves as a temporary file and is
 # automatically cleaned up.
-try-run = $(shell set -e;		\
+__try-run = set -e;			\
 	TMP="$(TMPOUT).$$$$.tmp";	\
 	TMPO="$(TMPOUT).$$$$.o";	\
 	if ($(1)) >/dev/null 2>&1;	\
 	then echo "$(2)";		\
 	else echo "$(3)";		\
 	fi;				\
-	rm -f "$$TMP" "$$TMPO")
+	rm -f "$$TMP" "$$TMPO"
+
+try-run = $(shell $(__try-run))
+
+# try-run-cached
+# This works like try-run, but the result is cached.
+try-run-cached = $(call shell-cached,$(__try-run))
 
 # as-option
 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
 
-as-option = $(call try-run,\
+as-option = $(call try-run-cached,\
 	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
 
 # as-instr
 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
 
-as-instr = $(call try-run,\
+as-instr = $(call try-run-cached,\
 	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
 
 # __cc-option
 # Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
-__cc-option = $(call try-run,\
+__cc-option = $(call try-run-cached,\
 	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
 
 # Do not attempt to build with gcc plugins during cc-option tests.
@@ -130,23 +203,23 @@ hostcc-option = $(call __cc-option, $(HOSTCC),\
 
 # cc-option-yn
 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
-cc-option-yn = $(call try-run,\
+cc-option-yn = $(call try-run-cached,\
 	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
 
 # cc-disable-warning
 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
-cc-disable-warning = $(call try-run,\
+cc-disable-warning = $(call try-run-cached,\
 	$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
 
 # cc-name
 # Expands to either gcc or clang
-cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
+cc-name = $(call shell-cached,$(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc)
 
 # cc-version
-cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
+cc-version = $(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
 
 # cc-fullversion
-cc-fullversion = $(shell $(CONFIG_SHELL) \
+cc-fullversion = $(call shell-cached,$(CONFIG_SHELL) \
 	$(srctree)/scripts/gcc-version.sh -p $(CC))
 
 # cc-ifversion
@@ -159,22 +232,23 @@ cc-if-fullversion = $(shell [ $(cc-fullversion) $(1) $(2) ] && echo $(3) || echo
 
 # cc-ldoption
 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
-cc-ldoption = $(call try-run,\
-	$(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
+cc-ldoption = $(call try-run-cached,\
+	$(CC) $(1) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))
 
 # ld-option
 # Usage: LDFLAGS += $(call ld-option, -X)
-ld-option = $(call try-run,\
-	$(CC) -x c /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
+ld-option = $(call try-run-cached,\
+	$(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -x c /dev/null -c -o "$$TMPO"; \
+	$(LD) $(LDFLAGS) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
 
 # ar-option
 # Usage: KBUILD_ARFLAGS := $(call ar-option,D)
 # Important: no spaces around options
-ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))
+ar-option = $(call try-run-cached, $(AR) rc$(1) "$$TMP",$(1),$(2))
 
 # ld-version
 # Note this is mainly for HJ Lu's 3 number binutil versions
-ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)
+ld-version = $(call shell-cached,$(LD) --version | $(srctree)/scripts/ld-version.sh)
 
 # ld-ifversion
 # Usage:  $(call ld-ifversion, -ge, 22252, y)

scripts/Makefile.asm-generic

@@ -6,6 +6,9 @@
 # and for each file listed in this file with generic-y creates
 # a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/$(src))
 
+PHONY := all
+all:
+
 kbuild-file := $(srctree)/arch/$(SRCARCH)/include/$(src)/Kbuild
 -include $(kbuild-file)
 

scripts/Makefile.build

@@ -65,15 +65,6 @@ ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(h
 include scripts/Makefile.host
 endif
 
-ifneq ($(KBUILD_SRC),)
-# 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
-
 ifndef obj
 $(warning kbuild: Makefile.build is included improperly)
 endif
@@ -563,7 +554,7 @@ $(multi-used-m): FORCE
 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
 
 targets += $(multi-used-y) $(multi-used-m)
-
+targets := $(filter-out $(PHONY), $(targets))
 
 # Descending
 # ---------------------------------------------------------------------------
@@ -584,13 +575,23 @@ FORCE:
 # optimization, we don't need to read them if the target does not
 # exist, we will rebuild anyway in that case.
 
-targets := $(wildcard $(sort $(targets)))
-cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
+cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
 
 ifneq ($(cmd_files),)
   include $(cmd_files)
 endif
 
+ifneq ($(KBUILD_SRC),)
+# Create directories for object files if they do not exist
+obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets))))
+# If cmd_files exist, their directories apparently exist.  Skip mkdir.
+exist-dirs := $(sort $(patsubst %/,%, $(dir $(cmd_files))))
+obj-dirs := $(strip $(filter-out $(exist-dirs), $(obj-dirs)))
+ifneq ($(obj-dirs),)
+$(shell mkdir -p $(obj-dirs))
+endif
+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.
 

scripts/Makefile.headersinst

@@ -27,11 +27,11 @@ subdirs       := $(patsubst $(srcdir)/%/,%,\
 # Recursion
 __headers: $(subdirs)
 
-.PHONY: $(subdirs)
+PHONY += $(subdirs)
 $(subdirs):
 	$(Q)$(MAKE) $(hdr-inst)=$(obj)/$@ dst=$(dst)/$@
 
-# Skip header install/check for include/uapi and arch/$(hdr-arch)/include/uapi.
+# Skip header install/check for include/uapi and arch/$(SRCARCH)/include/uapi.
 # We have only sub-directories there.
 skip-inst := $(if $(filter %/uapi,$(obj)),1)
 
@@ -115,9 +115,8 @@ $(check-file): scripts/headers_check.pl $(output-files) FORCE
 
 endif
 
-targets := $(wildcard $(sort $(targets)))
 cmd_files := $(wildcard \
-             $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
+             $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
 
 ifneq ($(cmd_files),)
 	include $(cmd_files)
@@ -125,6 +124,7 @@ endif
 
 endif # skip-inst
 
-.PHONY: $(PHONY)
 PHONY += FORCE
 FORCE: ;
+
+.PHONY: $(PHONY)

scripts/Makefile.help

-
-checker-help:
-	@echo  '  coccicheck      - Check with Coccinelle.'

scripts/Makefile.host

@@ -49,15 +49,6 @@ host-cxxobjs	:= $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))
 host-cshobjs	:= $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs))))
 host-cxxshobjs	:= $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs))))
 
-# output directory for programs/.o files
-# hostprogs-y := tools/build may have been specified.
-# Retrieve also directory of .o files from prog-objs or prog-cxxobjs notation
-host-objdirs := $(dir $(__hostprogs) $(host-cobjs) $(host-cxxobjs))
-
-host-objdirs := $(strip $(sort $(filter-out ./,$(host-objdirs))))
-
-
-__hostprogs     := $(addprefix $(obj)/,$(__hostprogs))
 host-csingle	:= $(addprefix $(obj)/,$(host-csingle))
 host-cmulti	:= $(addprefix $(obj)/,$(host-cmulti))
 host-cobjs	:= $(addprefix $(obj)/,$(host-cobjs))
@@ -67,9 +58,6 @@ host-cshlib	:= $(addprefix $(obj)/,$(host-cshlib))
 host-cxxshlib	:= $(addprefix $(obj)/,$(host-cxxshlib))
 host-cshobjs	:= $(addprefix $(obj)/,$(host-cshobjs))
 host-cxxshobjs	:= $(addprefix $(obj)/,$(host-cxxshobjs))
-host-objdirs    := $(addprefix $(obj)/,$(host-objdirs))
-
-obj-dirs += $(host-objdirs)
 
 #####
 # Handle options to gcc. Support building with separate output directory

scripts/Makefile.lib

@@ -5,24 +5,25 @@ ccflags-y  += $(EXTRA_CFLAGS)
 cppflags-y += $(EXTRA_CPPFLAGS)
 ldflags-y  += $(EXTRA_LDFLAGS)
 
-#
-# flags that take effect in sub directories
-export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)
-export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y)
+# flags that take effect in current and sub directories
+KBUILD_AFLAGS += $(subdir-asflags-y)
+KBUILD_CFLAGS += $(subdir-ccflags-y)
 
 # Figure out what we need to build from the various variables
 # ===========================================================================
 
 # When an object is listed to be built compiled-in and modular,
 # only build the compiled-in version
-
 obj-m := $(filter-out $(obj-y),$(obj-m))
 
 # Libraries are always collected in one lib file.
 # Filter out objects already built-in
-
 lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
 
+# Determine modorder.
+# Unfortunately, we don't have information about ordering between -y
+# and -m subdirs.  Just put -y's first.
+modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
 
 # Handle objects in subdirs
 # ---------------------------------------------------------------------------
@@ -30,12 +31,6 @@ lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
 #   and add the directory to the list of dirs to descend into: $(subdir-y)
 # o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
 #   and add the directory to the list of dirs to descend into: $(subdir-m)
-
-# Determine modorder.
-# Unfortunately, we don't have information about ordering between -y
-# and -m subdirs.  Just put -y's first.
-modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
-
 __subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
 subdir-y	+= $(__subdir-y)
 __subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
@@ -44,10 +39,9 @@ obj-y		:= $(patsubst %/, %/built-in.o, $(obj-y))
 obj-m		:= $(filter-out %/, $(obj-m))
 
 # Subdirectories we need to descend into
-
 subdir-ym	:= $(sort $(subdir-y) $(subdir-m))
 
-# if $(foo-objs) exists, foo.o is a composite object
+# if $(foo-objs), $(foo-y), or $(foo-m) exists, foo.o is a composite object
 multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
 multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m))))
 multi-used   := $(multi-used-y) $(multi-used-m)
@@ -57,15 +51,11 @@ single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m)))
 # objects depend on those (obviously)
 multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y)))
 multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y)))
-multi-objs   := $(multi-objs-y) $(multi-objs-m)
 
 # $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
 # tell kbuild to descend
 subdir-obj-y := $(filter %/built-in.o, $(obj-y))
 
-# $(obj-dirs) is a list of directories that contain object files
-obj-dirs := $(dir $(multi-objs) $(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=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m)))
@@ -93,11 +83,9 @@ multi-used-m	:= $(addprefix $(obj)/,$(multi-used-m))
 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))
 
 # These flags are needed for modversions and compiling, so we define them here
-# already
-# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will
+# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
 # end up in (or would, if it gets compiled in)
 # Note: Files that end up in two or more modules are compiled without the
 #       KBUILD_MODNAME definition. The reason is that any made-up name would
@@ -107,10 +95,10 @@ basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
 modname_flags  = $(if $(filter 1,$(words $(modname))),\
                  -DKBUILD_MODNAME=$(call name-fix,$(modname)))
 
-orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
+orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \
                  $(ccflags-y) $(CFLAGS_$(basetarget).o)
 _c_flags       = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
-orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \
+orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \
                  $(asflags-y) $(AFLAGS_$(basetarget).o)
 _a_flags       = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))
 _cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))

scripts/Makefile.modpost

@@ -143,8 +143,7 @@ FORCE:
 # optimization, we don't need to read them if the target does not
 # exist, we will rebuild anyway in that case.
 
-targets := $(wildcard $(sort $(targets)))
-cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
+cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
 
 ifneq ($(cmd_files),)
   include $(cmd_files)

scripts/link-vmlinux.sh

@@ -188,10 +188,8 @@ sortextable()
 # Delete output files in case of error
 cleanup()
 {
-	rm -f .old_version
 	rm -f .tmp_System.map
 	rm -f .tmp_kallsyms*
-	rm -f .tmp_version
 	rm -f .tmp_vmlinux*
 	rm -f built-in.o
 	rm -f System.map
@@ -239,12 +237,12 @@ esac
 
 # Update version
 info GEN .version
-if [ ! -r .version ]; then
-	rm -f .version;
-	echo 1 >.version;
+if [ -r .version ]; then
+	VERSION=$(expr 0$(cat .version) + 1)
+	echo $VERSION > .version
 else
-	mv .version .old_version;
-	expr 0$(cat .old_version) + 1 >.version;
+	rm -f .version
+	echo 1 > .version
 fi;
 
 # final build of init/
@@ -332,6 +330,3 @@ if [ -n "${CONFIG_KALLSYMS}" ]; then
 		exit 1
 	fi
 fi
-
-# We made a new kernel - delete old version file
-rm -f .old_version

scripts/mkcompile_h

@@ -28,12 +28,7 @@ LC_ALL=C
 export LC_ALL
 
 if [ -z "$KBUILD_BUILD_VERSION" ]; then
-	if [ -r .version ]; then
-		VERSION=`cat .version`
-	else
-		VERSION=0
-		echo 0 > .version
-	fi
+	VERSION=$(cat .version 2>/dev/null || echo 1)
 else
 	VERSION=$KBUILD_BUILD_VERSION
 fi

scripts/selinux/Makefile

 subdir-y := mdp genheaders
-subdir-	+= mdp genheaders