Merge tag 'kbuild-v4.17' of git://git.kernel.org/pub/scm/linux/kernel…

…/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - add a shell script to get Clang version

 - improve portability of build scripts

 - drop always-enabled CONFIG_THIN_ARCHIVE and remove unused code

 - rename built-in.o which is now thin archive to built-in.a

 - process clean/build targets one by one to get along with -j option

 - simplify ld-option

 - improve building with CONFIG_TRIM_UNUSED_KSYMS

 - define KBUILD_MODNAME even for objects shared among multiple modules

 - avoid linking multiple instances of same objects from composite
   objects

 - move <linux/compiler_types.h> to c_flags to include it only for C
   files

 - clean-up various Makefiles

* tag 'kbuild-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits)
  kbuild: get <linux/compiler_types.h> out of <linux/kconfig.h>
  kbuild: clean up link rule of composite modules
  kbuild: clean up archive rule of built-in.a
  kbuild: remove partial section mismatch detection for built-in.a
  net: liquidio: clean up Makefile for simpler composite object handling
  lib: zstd: clean up Makefile for simpler composite object handling
  kbuild: link $(real-obj-y) instead of $(obj-y) into built-in.a
  kbuild: rename real-objs-y/m to real-obj-y/m
  kbuild: move modname and modname-multi close to modname_flags
  kbuild: simplify modname calculation
  kbuild: fix modname for composite modules
  kbuild: define KBUILD_MODNAME even if multiple modules share objects
  kbuild: remove unnecessary $(subst $(obj)/, , ...) in modname-multi
  kbuild: Use ls(1) instead of stat(1) to obtain file size
  kbuild: link vmlinux only once for CONFIG_TRIM_UNUSED_KSYMS
  kbuild: move include/config/ksym/* to include/ksym/*
  kbuild: move CONFIG_TRIM_UNUSED_KSYMS code unneeded for external module
  kbuild: restore autoksyms.h touch to the top Makefile
  kbuild: move 'scripts' target below
  kbuild: remove wrong 'touch' in adjust_autoksyms.sh
  ...

.gitignore

@@ -87,6 +87,7 @@ modules.builtin
 #
 include/config
 include/generated
+include/ksym
 arch/*/include/generated
 
 # stgit generated dirs

Documentation/kbuild/kbuild.txt

@@ -50,10 +50,6 @@ LDFLAGS_MODULE
 --------------------------------------------------
 Additional options used for $(LD) when linking modules.
 
-LDFLAGS_vmlinux
---------------------------------------------------
-Additional options passed to final link of vmlinux.
-
 KBUILD_VERBOSE
 --------------------------------------------------
 Set the kbuild verbosity. Can be assigned same values as "V=...".

Documentation/kbuild/makefiles.txt

@@ -153,12 +153,18 @@ more details, with real examples.
 	configuration.
 
 	Kbuild compiles all the $(obj-y) files.  It then calls
-	"$(LD) -r" to merge these files into one built-in.o file.
-	built-in.o is later linked into vmlinux by the parent Makefile.
+	"$(AR) rcSTP" to merge these files into one built-in.a file.
+	This is a thin archive without a symbol table, which makes it
+	unsuitable as a linker input.
+
+	The scripts/link-vmlinux.sh script later makes an aggregate
+	built-in.a with "${AR} rcsTP", which creates the thin archive
+	with a symbol table and an index, making it a valid input for
+	the final vmlinux link passes.
 
 	The order of files in $(obj-y) is significant.  Duplicates in
 	the lists are allowed: the first instance will be linked into
-	built-in.o and succeeding instances will be ignored.
+	built-in.a and succeeding instances will be ignored.
 
 	Link order is significant, because certain functions
 	(module_init() / __initcall) will be called during boot in the
@@ -222,7 +228,7 @@ more details, with real examples.
 	Note: Of course, when you are building objects into the kernel,
 	the syntax above will also work. So, if you have CONFIG_EXT2_FS=y,
 	kbuild will build an ext2.o file for you out of the individual
-	parts and then link this into built-in.o, as you would expect.
+	parts and then link this into built-in.a, as you would expect.
 
 --- 3.4 Objects which export symbols
 
@@ -232,7 +238,7 @@ more details, with real examples.
 --- 3.5 Library file goals - lib-y
 
 	Objects listed with obj-* are used for modules, or
-	combined in a built-in.o for that specific directory.
+	combined in a built-in.a for that specific directory.
 	There is also the possibility to list objects that will
 	be included in a library, lib.a.
 	All objects listed with lib-y are combined in a single
@@ -244,7 +250,7 @@ more details, with real examples.
 
 	Note that the same kbuild makefile may list files to be built-in
 	and to be part of a library. Therefore the same directory
-	may contain both a built-in.o and a lib.a file.
+	may contain both a built-in.a and a lib.a file.
 
 	Example:
 		#arch/x86/lib/Makefile
@@ -831,12 +837,6 @@ When kbuild executes, the following steps are followed (roughly):
 	Note: ldflags-y can be used to further customise
 	the flags used. See chapter 3.7.
 
-    LDFLAGS_MODULE	Options for $(LD) when linking modules
-
-	LDFLAGS_MODULE is used to set specific flags for $(LD) when
-	linking the .ko files used for modules.
-	Default is "-r", for relocatable output.
-
     LDFLAGS_vmlinux	Options for $(LD) when linking vmlinux
 
 	LDFLAGS_vmlinux is used to specify additional flags to pass to
@@ -986,7 +986,7 @@ When kbuild executes, the following steps are followed (roughly):
 
 	$(head-y) lists objects to be linked first in vmlinux.
 	$(libs-y) lists directories where a lib.a archive can be located.
-	The rest list directories where a built-in.o object file can be
+	The rest list directories where a built-in.a object file can be
 	located.
 
 	$(init-y) objects will be located after $(head-y).
@@ -1071,7 +1071,7 @@ When kbuild executes, the following steps are followed (roughly):
 		extra-y := head.o init_task.o
 
 	In this example, extra-y is used to list object files that
-	shall be built, but shall not be linked as part of built-in.o.
+	shall be built, but shall not be linked as part of built-in.a.
 
 
 --- 6.7 Commands useful for building a boot image

Documentation/process/changes.rst

@@ -78,7 +78,7 @@ Binutils
 --------
 
 The build system has, as of 4.13, switched to using thin archives (`ar T`)
-rather than incremental linking (`ld -r`) for built-in.o intermediate steps.
+rather than incremental linking (`ld -r`) for built-in.a intermediate steps.
 This requires binutils 2.20 or newer.
 
 Flex

Makefile

@@ -35,7 +35,7 @@ unexport GREP_OPTIONS
 # Most importantly: sub-Makefiles should only ever modify files in
 # their own directory. If in some directory we have a dependency on
 # a file in another dir (which doesn't happen often, but it's often
-# unavoidable when linking the built-in.o targets which finally
+# unavoidable when linking the built-in.a targets which finally
 # turn into vmlinux), we will call a sub make in that other dir, and
 # after that we are sure that everything which is in that other dir
 # is now up to date.
@@ -220,7 +220,8 @@ export srctree objtree VPATH
 version_h := include/generated/uapi/linux/version.h
 old_version_h := include/linux/version.h
 
-no-dot-config-targets := clean mrproper distclean \
+clean-targets := %clean mrproper cleandocs
+no-dot-config-targets := $(clean-targets) \
 			 cscope gtags TAGS tags help% %docs check% coccicheck \
 			 $(version_h) headers_% archheaders archscripts \
 			 kernelversion %src-pkg
@@ -243,6 +244,14 @@ ifeq ($(KBUILD_EXTMOD),)
                 endif
         endif
 endif
+
+# For "make -j clean all", "make -j mrproper defconfig all", etc.
+ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
+        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
+                mixed-targets := 1
+        endif
+endif
+
 # install and modules_install need also be processed one by one
 ifneq ($(filter install,$(MAKECMDGOALS)),)
         ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
@@ -418,6 +427,7 @@ KBUILD_CFLAGS_KERNEL :=
 KBUILD_AFLAGS_MODULE  := -DMODULE
 KBUILD_CFLAGS_MODULE  := -DMODULE
 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
+LDFLAGS :=
 GCC_PLUGINS_CFLAGS :=
 
 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
@@ -556,14 +566,6 @@ endif
 export KBUILD_MODULES KBUILD_BUILTIN
 
 ifeq ($(KBUILD_EXTMOD),)
-# Additional helpers built in scripts/
-# Carefully list dependencies so we do not try to build scripts twice
-# in parallel
-PHONY += scripts
-scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
-	 asm-generic gcc-plugins
-	$(Q)$(MAKE) $(build)=$(@)
-
 # Objects we will link into vmlinux / subdirs we need to visit
 init-y		:= init/
 drivers-y	:= drivers/ sound/ firmware/
@@ -611,13 +613,6 @@ else
 include/config/auto.conf: ;
 endif # $(dot-config)
 
-# For the kernel to actually contain only the needed exported symbols,
-# we have to build modules as well to determine what those symbols are.
-# (this can be evaluated only once include/config/auto.conf has been included)
-ifdef CONFIG_TRIM_UNUSED_KSYMS
-  KBUILD_MODULES := 1
-endif
-
 # The all: target is the default when no target is given on the
 # command line.
 # This allow a user to issue only 'make' to build a kernel including modules
@@ -984,13 +979,13 @@ vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
 vmlinux-alldirs	:= $(sort $(vmlinux-dirs) $(patsubst %/,%,$(filter %/, \
 		     $(init-) $(core-) $(drivers-) $(net-) $(libs-) $(virt-))))
 
-init-y		:= $(patsubst %/, %/built-in.o, $(init-y))
-core-y		:= $(patsubst %/, %/built-in.o, $(core-y))
-drivers-y	:= $(patsubst %/, %/built-in.o, $(drivers-y))
-net-y		:= $(patsubst %/, %/built-in.o, $(net-y))
+init-y		:= $(patsubst %/, %/built-in.a, $(init-y))
+core-y		:= $(patsubst %/, %/built-in.a, $(core-y))
+drivers-y	:= $(patsubst %/, %/built-in.a, $(drivers-y))
+net-y		:= $(patsubst %/, %/built-in.a, $(net-y))
 libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
-libs-y2		:= $(filter-out %.a, $(patsubst %/, %/built-in.o, $(libs-y)))
-virt-y		:= $(patsubst %/, %/built-in.o, $(virt-y))
+libs-y2		:= $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
+virt-y		:= $(patsubst %/, %/built-in.a, $(virt-y))
 
 # Externally visible symbols (used by link-vmlinux.sh)
 export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
@@ -1003,25 +998,26 @@ export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Doc
 
 vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN) $(KBUILD_VMLINUX_LIBS)
 
-# Include targets which we want to execute sequentially if the rest of the
-# kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
-# evaluated more than once.
-PHONY += vmlinux_prereq
-vmlinux_prereq: $(vmlinux-deps) FORCE
-ifdef CONFIG_HEADERS_CHECK
-	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
-endif
-ifdef CONFIG_GDB_SCRIPTS
-	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
-endif
+# Recurse until adjust_autoksyms.sh is satisfied
+PHONY += autoksyms_recursive
+autoksyms_recursive: $(vmlinux-deps)
 ifdef CONFIG_TRIM_UNUSED_KSYMS
 	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
 	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
 endif
 
-# standalone target for easier testing
-include/generated/autoksyms.h: FORCE
-	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
+# For the kernel to actually contain only the needed exported symbols,
+# we have to build modules as well to determine what those symbols are.
+# (this can be evaluated only once include/config/auto.conf has been included)
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+  KBUILD_MODULES := 1
+endif
+
+autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
+
+$(autoksyms_h):
+	$(Q)mkdir -p $(dir $@)
+	$(Q)touch $@
 
 ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
 
@@ -1030,7 +1026,13 @@ cmd_link-vmlinux =                                                 \
 	$(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) ;    \
 	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
 
-vmlinux: scripts/link-vmlinux.sh vmlinux_prereq $(vmlinux-deps) FORCE
+vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
+ifdef CONFIG_HEADERS_CHECK
+	$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
+endif
+ifdef CONFIG_GDB_SCRIPTS
+	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
+endif
 	+$(call if_changed,link-vmlinux)
 
 # Build samples along the rest of the kernel
@@ -1060,6 +1062,13 @@ endef
 include/config/kernel.release: include/config/auto.conf FORCE
 	$(call filechk,kernel.release)
 
+# Additional helpers built in scripts/
+# Carefully list dependencies so we do not try to build scripts twice
+# in parallel
+PHONY += scripts
+scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
+	 asm-generic gcc-plugins $(autoksyms_h)
+	$(Q)$(MAKE) $(build)=$(@)
 
 # Things we need to do before we recursively start building the kernel
 # or the modules are listed in "prepare".
@@ -1088,7 +1097,7 @@ endif
 # that need to depend on updated CONFIG_* values can be checked here.
 prepare2: prepare3 prepare-compiler-check outputmakefile asm-generic
 
-prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
+prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
                    include/config/auto.conf
 	$(cmd_crmodverdir)
 
@@ -1327,7 +1336,7 @@ endif # CONFIG_MODULES
 # make distclean Remove editor backup files, patch leftover files and the like
 
 # Directories & files removed with 'make clean'
-CLEAN_DIRS  += $(MODVERDIR)
+CLEAN_DIRS  += $(MODVERDIR) include/ksym
 
 # Directories & files removed with 'make mrproper'
 MRPROPER_DIRS  += include/config usr/include include/generated          \

arch/Kconfig

@@ -596,12 +596,6 @@ config CC_STACKPROTECTOR_AUTO
 
 endchoice
 
-config THIN_ARCHIVES
-	def_bool y
-	help
-	  Select this if the architecture wants to use thin archives
-	  instead of ld -r to create the built-in.o files.
-
 config LD_DEAD_CODE_DATA_ELIMINATION
 	bool
 	help

arch/arm/boot/deflate_xip_data.sh

@@ -45,7 +45,7 @@ data_start=$(($__data_loc - $base_offset))
 data_end=$(($_edata_loc - $base_offset))
 
 # Make sure data occupies the last part of the file.
-file_end=$(stat -c "%s" "$XIPIMAGE")
+file_end=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" "$XIPIMAGE")
 if [ "$file_end" != "$data_end" ]; then
 	printf "end of xipImage doesn't match with _edata_loc (%#x vs %#x)\n" \
 	       $(($file_end + $base_offset)) $_edata_loc 1>&2

arch/powerpc/boot/wrapper

@@ -355,7 +355,7 @@ vmz="$tmpdir/`basename \"$kernel\"`.$ext"
 
 # Calculate the vmlinux.strip size
 ${CROSS}objcopy $objflags "$kernel" "$vmz.$$"
-strip_size=$(stat -c %s $vmz.$$)
+strip_size=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" "$vmz.$$")
 
 if [ -z "$cacheit" -o ! -f "$vmz$compression" -o "$vmz$compression" -ot "$kernel" ]; then
     # recompress the image if we need to

arch/powerpc/kernel/Makefile

@@ -165,7 +165,7 @@ systbl_chk: $(src)/systbl_chk.sh $(obj)/systbl_chk.i
 	$(call cmd,systbl_chk)
 
 ifeq ($(CONFIG_PPC_OF_BOOT_TRAMPOLINE),y)
-$(obj)/built-in.o:		prom_init_check
+$(obj)/built-in.a:		prom_init_check
 
 quiet_cmd_prom_init_check = CALL    $<
       cmd_prom_init_check = $(CONFIG_SHELL) $< "$(NM)" "$(obj)/prom_init.o"

drivers/net/ethernet/cavium/liquidio/Makefile

@@ -2,42 +2,23 @@
 #
 # Cavium Liquidio ethernet device driver
 #
-obj-$(CONFIG_LIQUIDIO) += liquidio.o
 
-liquidio-$(CONFIG_LIQUIDIO) += lio_ethtool.o \
-			lio_core.o         \
-			request_manager.o  \
-			response_manager.o \
-			octeon_device.o    \
-			cn66xx_device.o    \
-			cn68xx_device.o    \
-			cn23xx_pf_device.o \
-			cn23xx_vf_device.o \
-			octeon_mailbox.o   \
-			octeon_mem_ops.o   \
-			octeon_droq.o      \
-			octeon_nic.o
+common-objs :=	lio_ethtool.o		\
+		lio_core.o		\
+		request_manager.o	\
+		response_manager.o	\
+		octeon_device.o		\
+		cn66xx_device.o		\
+		cn68xx_device.o		\
+		cn23xx_pf_device.o	\
+		cn23xx_vf_device.o	\
+		octeon_mailbox.o	\
+		octeon_mem_ops.o	\
+		octeon_droq.o		\
+		octeon_nic.o
 
-liquidio-objs := lio_main.o octeon_console.o lio_vf_rep.o $(liquidio-y)
+obj-$(CONFIG_LIQUIDIO) += liquidio.o
+liquidio-y := lio_main.o octeon_console.o lio_vf_rep.o $(common-objs)
 
 obj-$(CONFIG_LIQUIDIO_VF) += liquidio_vf.o
-
-ifeq ($(CONFIG_LIQUIDIO)$(CONFIG_LIQUIDIO_VF), yy)
-	liquidio_vf-objs := lio_vf_main.o
-else
-liquidio_vf-$(CONFIG_LIQUIDIO_VF) += lio_ethtool.o \
-			lio_core.o         \
-			request_manager.o  \
-			response_manager.o \
-			octeon_device.o    \
-			cn66xx_device.o    \
-			cn68xx_device.o    \
-			cn23xx_pf_device.o \
-			cn23xx_vf_device.o \
-			octeon_mailbox.o   \
-			octeon_mem_ops.o   \
-			octeon_droq.o      \
-			octeon_nic.o
-
-liquidio_vf-objs := lio_vf_main.o $(liquidio_vf-y)
-endif
+liquidio_vf-y := lio_vf_main.o $(common-objs)

drivers/s390/Makefile

@@ -5,5 +5,5 @@
 
 obj-y += cio/ block/ char/ crypto/ net/ scsi/ virtio/
 
-drivers-y += drivers/s390/built-in.o
+drivers-y += drivers/s390/built-in.a