Merge tag 'kbuild-fixes-v4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix O= building on dash

 - remove unused dependency in Makefile

 - fix default of a choice in Kconfig

 - fix typos and documentation style

 - fix command options unrecognized by sparse

* tag 'kbuild-fixes-v4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: clang: fix build failures with sparse check
  kbuild doc: a bundle of fixes on makefiles.txt
  Makefile: kselftest: fix grammar typo
  kbuild: Fix optimization level choice default
  kbuild: drop unused symverfile in Makefile.modpost
  kbuild: revert $(realpath ...) to $(shell cd ... && /bin/pwd)

Author: torvalds

Documentation/kbuild/makefiles.txt

@@ -1108,14 +1108,6 @@ When kbuild executes, the following steps are followed (roughly):
     ld
 	Link target. Often, LDFLAGS_$@ is used to set specific options to ld.
 
-    objcopy
-	Copy binary. Uses OBJCOPYFLAGS usually specified in
-	arch/$(ARCH)/Makefile.
-	OBJCOPYFLAGS_$@ may be used to set additional options.
-
-    gzip
-	Compress target. Use maximum compression to compress target.
-
 	Example:
 		#arch/x86/boot/Makefile
 		LDFLAGS_bootsect := -Ttext 0x0 -s --oformat binary
@@ -1139,6 +1131,19 @@ When kbuild executes, the following steps are followed (roughly):
 	      resulting in the target file being recompiled for no
 	      obvious reason.
 
+    objcopy
+	Copy binary. Uses OBJCOPYFLAGS usually specified in
+	arch/$(ARCH)/Makefile.
+	OBJCOPYFLAGS_$@ may be used to set additional options.
+
+    gzip
+	Compress target. Use maximum compression to compress target.
+
+	Example:
+		#arch/x86/boot/compressed/Makefile
+		$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
+			$(call if_changed,gzip)
+
     dtc
 	Create flattened device tree blob object suitable for linking
 	into vmlinux. Device tree blobs linked into vmlinux are placed
@@ -1219,7 +1224,7 @@ When kbuild executes, the following steps are followed (roughly):
 	that may be shared between individual architectures.
 	The recommended approach how to use a generic header file is
 	to list the file in the Kbuild file.
-	See "7.3 generic-y" for further info on syntax etc.
+	See "7.2 generic-y" for further info on syntax etc.
 
 --- 6.11 Post-link pass
 
@@ -1254,13 +1259,13 @@ A Kbuild file may be defined under arch/<arch>/include/uapi/asm/ and
 arch/<arch>/include/asm/ to list asm files coming from asm-generic.
 See subsequent chapter for the syntax of the Kbuild file.
 
-	--- 7.1 no-export-headers
+--- 7.1 no-export-headers
 
 	no-export-headers is essentially used by include/uapi/linux/Kbuild to
 	avoid exporting specific headers (e.g. kvm.h) on architectures that do
 	not support it. It should be avoided as much as possible.
 
-	--- 7.2 generic-y
+--- 7.2 generic-y
 
 	If an architecture uses a verbatim copy of a header from
 	include/asm-generic then this is listed in the file
@@ -1287,7 +1292,7 @@ See subsequent chapter for the syntax of the Kbuild file.
 		Example: termios.h
 			#include <asm-generic/termios.h>
 
-	--- 7.3 generated-y
+--- 7.3 generated-y
 
 	If an architecture generates other header files alongside generic-y
 	wrappers, generated-y specifies them.
@@ -1299,7 +1304,7 @@ See subsequent chapter for the syntax of the Kbuild file.
 			#arch/x86/include/asm/Kbuild
 			generated-y += syscalls_32.h
 
-	--- 7.5 mandatory-y
+--- 7.4 mandatory-y
 
 	mandatory-y is essentially used by include/uapi/asm-generic/Kbuild.asm
 	to define the minimum set of headers that must be exported in

Makefile

@@ -130,8 +130,8 @@ endif
 ifneq ($(KBUILD_OUTPUT),)
 # check that the output directory actually exists
 saved-output := $(KBUILD_OUTPUT)
-$(shell [ -d $(KBUILD_OUTPUT) ] || mkdir -p $(KBUILD_OUTPUT))
-KBUILD_OUTPUT := $(realpath $(KBUILD_OUTPUT))
+KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
+								&& /bin/pwd)
 $(if $(KBUILD_OUTPUT),, \
      $(error failed to create output directory "$(saved-output)"))
 
@@ -697,11 +697,11 @@ KBUILD_CFLAGS += $(stackp-flag)
 
 ifeq ($(cc-name),clang)
 ifneq ($(CROSS_COMPILE),)
-CLANG_TARGET	:= -target $(notdir $(CROSS_COMPILE:%-=%))
+CLANG_TARGET	:= --target=$(notdir $(CROSS_COMPILE:%-=%))
 GCC_TOOLCHAIN	:= $(realpath $(dir $(shell which $(LD)))/..)
 endif
 ifneq ($(GCC_TOOLCHAIN),)
-CLANG_GCC_TC	:= -gcc-toolchain $(GCC_TOOLCHAIN)
+CLANG_GCC_TC	:= --gcc-toolchain=$(GCC_TOOLCHAIN)
 endif
 KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
 KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC)
@@ -1399,7 +1399,7 @@ help:
 	@echo  '                    Build, install, and boot kernel before'
 	@echo  '                    running kselftest on it'
 	@echo  '  kselftest-clean - Remove all generated kselftest files'
-	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existed'
+	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
 	@echo  '                    .config.'
 	@echo  ''
 	@echo 'Userspace tools targets:'

init/Kconfig

@@ -1033,7 +1033,7 @@ endif
 
 choice
 	prompt "Compiler optimization level"
-	default CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
+	default CC_OPTIMIZE_FOR_PERFORMANCE
 
 config CC_OPTIMIZE_FOR_PERFORMANCE
 	bool "Optimize for performance"

scripts/Makefile.modpost

@@ -97,7 +97,6 @@ vmlinux.o: FORCE
 	$(call cmd,kernel-mod)
 
 # Declare generated files as targets for modpost
-$(symverfile):         __modpost ;
 $(modules:.ko=.mod.c): __modpost ;
 
 

tools/power/cpupower/Makefile

@@ -26,7 +26,7 @@ endif
 
 ifneq ($(OUTPUT),)
 # check that the output directory actually exists
-OUTDIR := $(realpath $(OUTPUT))
+OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd)
 $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
 endif
 

tools/scripts/Makefile.include

@@ -1,7 +1,7 @@
 ifneq ($(O),)
 ifeq ($(origin O), command line)
-	ABSOLUTE_O := $(realpath $(O))
-	dummy := $(if $(ABSOLUTE_O),,$(error O=$(O) does not exist))
+	dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
+	ABSOLUTE_O := $(shell cd $(O) ; pwd)
 	OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/)
 	COMMAND_O := O=$(ABSOLUTE_O)
 ifeq ($(objtree),)
@@ -12,7 +12,7 @@ endif
 
 # check that the output directory actually exists
 ifneq ($(OUTPUT),)
-OUTDIR := $(realpath $(OUTPUT))
+OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd)
 $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
 endif