Merge tag 'kbuild-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "Kbuild core:
   - remove unneeded $(call cc-option,...) switches
   - consolidate Clang compiler flags into CLANG_FLAGS
   - announce the deprecation of SUBDIRS
   - fix single target build for external module
   - simplify the dependencies of 'prepare' stage targets
   - allow fixdep to directly write to .*.cmd files
   - simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS
   - change if_changed_rule to accept multi-line recipe
   - move .SECONDARY special target to scripts/Kbuild.include
   - remove redundant 'set -e'
   - improve parallel execution for CONFIG_HEADERS_CHECK
   - misc cleanups

  Treewide fixes and cleanups
   - set Clang flags correctly for PowerPC boot images
   - fix UML build error with CONFIG_GCC_PLUGINS
   - remove unneeded patterns from .gitignore files
   - refactor firmware/Makefile
   - remove unneeded rules for *offsets.s
   - avoid unneeded regeneration of intermediate .s files
   - clean up ./Kbuild

  Modpost:
   - remove unused -M, -K options
   - fix false positive warnings about section mismatch
   - use simple devtable lookup instead of linker magic
   - misc cleanups

  Coccinelle:
   - relax boolinit.cocci checks for overall consistency
   - fix warning messages of boolinit.cocci

  Other tools:
   - improve -dirty check of scripts/setlocalversion
   - add a tool to generate compile_commands.json from .*.cmd files"

* tag 'kbuild-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (51 commits)
  kbuild: remove unused cmd_gentimeconst
  kbuild: remove $(obj)/ prefixes in ./Kbuild
  treewide: add intermediate .s files to targets
  treewide: remove explicit rules for *offsets.s
  firmware: refactor firmware/Makefile
  firmware: remove unnecessary patterns from .gitignore
  scripts: remove unnecessary ihex2fw and check-lc_ctypes from .gitignore
  um: remove unused filechk_gen_header in Makefile
  scripts: add a tool to produce a compile_commands.json file
  kbuild: add -Werror=implicit-int flag unconditionally
  kbuild: add -Werror=strict-prototypes flag unconditionally
  kbuild: add -fno-PIE flag unconditionally
  scripts: coccinelle: Correct warning message
  scripts: coccinelle: only suggest true/false in files that already use them
  kbuild: handle part-of-module correctly for *.ll and *.symtypes
  kbuild: refactor part-of-module
  kbuild: refactor quiet_modtag
  kbuild: remove redundant quiet_modtag for $(obj-m)
  kbuild: refactor Makefile.asm-generic
  user/Makefile: Fix typo and capitalization in comment section
  ...

8 files changed, 19 insertions, 38 deletions

diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
index b65d6bfab8e6..4180f3a13512 100644
--- a/arch/arm/crypto/Makefile
+++ b/arch/arm/crypto/Makefile
@@ -67,4 +67,4 @@ $(src)/sha512-core.S_shipped: $(src)/sha512-armv4.pl
 	$(call cmd,perl)
 endif
 
-targets += sha256-core.S sha512-core.S
+clean-files += sha256-core.S sha512-core.S
diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index 7415f181907b..31b61f0e1c07 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -19,10 +19,9 @@ ifeq ($(CONFIG_PM_DEBUG),y)
 CFLAGS_pm.o += -DDEBUG
 endif
 
-arch/arm/mach-at91/pm_data-offsets.s: arch/arm/mach-at91/pm_data-offsets.c
-	$(call if_changed_dep,cc_s_c)
-
 include/generated/at91_pm_data-offsets.h: arch/arm/mach-at91/pm_data-offsets.s FORCE
 	$(call filechk,offsets,__PM_DATA_OFFSETS_H__)
 
 arch/arm/mach-at91/pm_suspend.o: include/generated/at91_pm_data-offsets.h
+
+targets += pm_data-offsets.s
diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
index 899c60fac159..85d1b13c9215 100644
--- a/arch/arm/mach-omap2/Makefile
+++ b/arch/arm/mach-omap2/Makefile
@@ -236,10 +236,9 @@ obj-y					+= omap_phy_internal.o
 
 obj-$(CONFIG_MACH_OMAP2_TUSB6010)	+= usb-tusb6010.o
 
-arch/arm/mach-omap2/pm-asm-offsets.s: arch/arm/mach-omap2/pm-asm-offsets.c
-	$(call if_changed_dep,cc_s_c)
-
 include/generated/ti-pm-asm-offsets.h: arch/arm/mach-omap2/pm-asm-offsets.s FORCE
 	$(call filechk,offsets,__TI_PM_ASM_OFFSETS_H__)
 
 $(obj)/sleep33xx.o $(obj)/sleep43xx.o: include/generated/ti-pm-asm-offsets.h
+
+targets += pm-asm-offsets.s
diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile
index a4ffd9fe3265..e766daf43b7c 100644
--- a/arch/arm64/crypto/Makefile
+++ b/arch/arm64/crypto/Makefile
@@ -78,4 +78,4 @@ $(src)/sha512-core.S_shipped: $(src)/sha512-armv8.pl
 	$(call cmd,perlasm)
 endif
 
-targets += sha256-core.S sha512-core.S
+clean-files += sha256-core.S sha512-core.S
diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile
index d0c0ccdd656a..4ba05140b249 100644
--- a/arch/ia64/kernel/Makefile
+++ b/arch/ia64/kernel/Makefile
@@ -50,10 +50,7 @@ CFLAGS_traps.o  += -mfixed-range=f2-f5,f16-f31
 # The gate DSO image is built using a special linker script.
 include $(src)/Makefile.gate
 
-# We use internal kbuild rules to avoid the "is up to date" message from make
-arch/$(SRCARCH)/kernel/nr-irqs.s: arch/$(SRCARCH)/kernel/nr-irqs.c
-	$(Q)mkdir -p $(dir $@)
-	$(call if_changed_dep,cc_s_c)
-
 include/generated/nr-irqs.h: arch/$(SRCARCH)/kernel/nr-irqs.s FORCE
 	$(call filechk,offsets,__ASM_NR_IRQS_H__)
+
+targets += nr-irqs.s
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index ed9883169190..0e8dadd011bc 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -55,6 +55,11 @@ BOOTAFLAGS	:= -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc
 
 BOOTARFLAGS	:= -cr$(KBUILD_ARFLAGS)
 
+ifdef CONFIG_CC_IS_CLANG
+BOOTCFLAGS += $(CLANG_FLAGS)
+BOOTAFLAGS += $(CLANG_FLAGS)
+endif
+
 ifdef CONFIG_DEBUG_INFO
 BOOTCFLAGS	+= -g
 endif
diff --git a/arch/um/Makefile b/arch/um/Makefile
index ab1066c38944..273130cf91d1 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -23,8 +23,6 @@ OS := $(shell uname -s)
 # features.
 SHELL := /bin/bash
 
-filechk_gen_header = $<
-
 core-y			+= $(ARCH_DIR)/kernel/		\
 			   $(ARCH_DIR)/drivers/		\
 			   $(ARCH_DIR)/os-$(OS)/
@@ -116,7 +114,8 @@ endef
 archheaders:
 	$(Q)$(MAKE) -f $(srctree)/Makefile ARCH=$(HEADER_ARCH) asm-generic archheaders
 
-archprepare: include/generated/user_constants.h
+archprepare:
+	$(Q)$(MAKE) $(build)=$(HOST_DIR)/um include/generated/user_constants.h
 
 LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static
 LINK-$(CONFIG_LD_SCRIPT_DYN) += -Wl,-rpath,/lib $(call cc-option, -no-pie)
@@ -146,25 +145,4 @@ archclean:
 	@find . \( -name '*.bb' -o -name '*.bbg' -o -name '*.da' \
 		-o -name '*.gcov' \) -type f -print | xargs rm -f
 
-# Generated files
-
-$(HOST_DIR)/um/user-offsets.s: __headers FORCE
-	$(Q)$(MAKE) $(build)=$(HOST_DIR)/um $@
-
-define filechk_gen-asm-offsets
-        (set -e; \
-         echo "/*"; \
-         echo " * DO NOT MODIFY."; \
-         echo " *"; \
-         echo " * This file was generated by arch/$(ARCH)/Makefile"; \
-         echo " *"; \
-         echo " */"; \
-         echo ""; \
-         sed -ne "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}" < $<; \
-         echo ""; )
-endef
-
-include/generated/user_constants.h: $(HOST_DIR)/um/user-offsets.s
-	$(call filechk,gen-asm-offsets)
-
 export HEADER_ARCH SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING OS DEV_NULL_PATH
diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile
index c2d3d7c51e9e..2d686ae54681 100644
--- a/arch/x86/um/Makefile
+++ b/arch/x86/um/Makefile
@@ -36,9 +36,12 @@ subarch-$(CONFIG_MODULES) += ../kernel/module.o
 
 USER_OBJS := bugs_$(BITS).o ptrace_user.o fault.o
 
-extra-y += user-offsets.s
 $(obj)/user-offsets.s: c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) \
 	-Iarch/x86/include/generated
+targets += user-offsets.s
+
+include/generated/user_constants.h: $(obj)/user-offsets.s
+	$(call filechk,offsets,__USER_CONSTANT_H__)
 
 UNPROFILE_OBJS := stub_segv.o
 CFLAGS_stub_segv.o := $(CFLAGS_NO_HARDENING)