Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Fix false-positive build warnings for ARCH=ia64 builds

 - Optimize dictionary size for module compression with xz

 - Check the compiler and linker versions in Kconfig

 - Fix misuse of extra-y

 - Support DWARF v5 debug info

 - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
   exceeded the limit

 - Add generic syscall{tbl,hdr}.sh for cleanups across arches

 - Minor cleanups of genksyms

 - Minor cleanups of Kconfig

* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
  initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
  kbuild: remove deprecated 'always' and 'hostprogs-y/m'
  kbuild: parse C= and M= before changing the working directory
  kbuild: reuse this-makefile to define abs_srctree
  kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
  kconfig: omit --oldaskconfig option for 'make config'
  kconfig: fix 'invalid option' for help option
  kconfig: remove dead code in conf_askvalue()
  kconfig: clean up nested if-conditionals in check_conf()
  kconfig: Remove duplicate call to sym_get_string_value()
  Makefile: Remove # characters from compiler string
  Makefile: reuse CC_VERSION_TEXT
  kbuild: check the minimum linker version in Kconfig
  kbuild: remove ld-version macro
  scripts: add generic syscallhdr.sh
  scripts: add generic syscalltbl.sh
  arch: syscalls: remove $(srctree)/ prefix from syscall tables
  arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
  gen_compile_commands: prune some directories
  kbuild: simplify access to the kernel's version
  ...

1 files changed, 57 insertions, 48 deletions

diff --git a/Makefile b/Makefile
index b18dbc634690..6ecd0d22e608 100644
--- a/Makefile
+++ b/Makefile
@@ -100,6 +100,36 @@ endif
 
 export quiet Q KBUILD_VERBOSE
 
+# Call a source code checker (by default, "sparse") as part of the
+# C compilation.
+#
+# Use 'make C=1' to enable checking of only re-compiled files.
+# Use 'make C=2' to enable checking of *all* source files, regardless
+# of whether they are re-compiled or not.
+#
+# See the file "Documentation/dev-tools/sparse.rst" for more details,
+# including where to get the "sparse" utility.
+
+ifeq ("$(origin C)", "command line")
+  KBUILD_CHECKSRC = $(C)
+endif
+ifndef KBUILD_CHECKSRC
+  KBUILD_CHECKSRC = 0
+endif
+
+export KBUILD_CHECKSRC
+
+# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
+# directory of external module to build. Setting M= takes precedence.
+ifeq ("$(origin M)", "command line")
+  KBUILD_EXTMOD := $(M)
+endif
+
+$(if $(word 2, $(KBUILD_EXTMOD)), \
+	$(error building multiple external modules is not supported))
+
+export KBUILD_EXTMOD
+
 # Kbuild will save output files in the current working directory.
 # This does not need to match to the root of the kernel source tree.
 #
@@ -145,7 +175,8 @@ else
 need-sub-make := 1
 endif
 
-abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
+this-makefile := $(lastword $(MAKEFILE_LIST))
+abs_srctree := $(realpath $(dir $(this-makefile)))
 
 ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
 $(error source directory cannot contain spaces or colons)
@@ -160,8 +191,6 @@ MAKEFLAGS += --include-dir=$(abs_srctree)
 need-sub-make := 1
 endif
 
-this-makefile := $(lastword $(MAKEFILE_LIST))
-
 ifneq ($(filter 3.%,$(MAKE_VERSION)),)
 # 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
 # We need to invoke sub-make to avoid implicit rules in the top Makefile.
@@ -195,36 +224,6 @@ ifeq ($(need-sub-make),)
 # so that IDEs/editors are able to understand relative filenames.
 MAKEFLAGS += --no-print-directory
 
-# Call a source code checker (by default, "sparse") as part of the
-# C compilation.
-#
-# Use 'make C=1' to enable checking of only re-compiled files.
-# Use 'make C=2' to enable checking of *all* source files, regardless
-# of whether they are re-compiled or not.
-#
-# See the file "Documentation/dev-tools/sparse.rst" for more details,
-# including where to get the "sparse" utility.
-
-ifeq ("$(origin C)", "command line")
-  KBUILD_CHECKSRC = $(C)
-endif
-ifndef KBUILD_CHECKSRC
-  KBUILD_CHECKSRC = 0
-endif
-
-# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
-# directory of external module to build. Setting M= takes precedence.
-ifeq ("$(origin M)", "command line")
-  KBUILD_EXTMOD := $(M)
-endif
-
-$(if $(word 2, $(KBUILD_EXTMOD)), \
-	$(error building multiple external modules is not supported))
-
-export KBUILD_CHECKSRC KBUILD_EXTMOD
-
-extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
-
 ifeq ($(abs_srctree),$(abs_objtree))
         # building in the source tree
         srctree := .
@@ -257,7 +256,6 @@ export building_out_of_srctree srctree objtree VPATH
 # of make so .config is not included in this case either (for *config).
 
 version_h := include/generated/uapi/linux/version.h
-old_version_h := include/linux/version.h
 
 clean-targets := %clean mrproper cleandocs
 no-dot-config-targets := $(clean-targets) \
@@ -558,7 +556,13 @@ ifdef building_out_of_srctree
 	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
 endif
 
-ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
+# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
+# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
+# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
+# and from include/config/auto.conf.cmd to detect the compiler upgrade.
+CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1 | sed 's/\#//g')
+
+ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 ifneq ($(CROSS_COMPILE),)
 CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
@@ -577,12 +581,6 @@ KBUILD_AFLAGS	+= $(CLANG_FLAGS)
 export CLANG_FLAGS
 endif
 
-# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
-# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
-# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
-# and from include/config/auto.conf.cmd to detect the compiler upgrade.
-CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
-
 ifdef config-build
 # ===========================================================================
 # *config targets only - make sure prerequisites are updated, and descend
@@ -832,8 +830,10 @@ ifneq ($(LLVM_IAS),1)
 KBUILD_AFLAGS	+= -Wa,-gdwarf-2
 endif
 
-ifdef CONFIG_DEBUG_INFO_DWARF4
-DEBUG_CFLAGS	+= -gdwarf-4
+ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
+dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
+dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5
+DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
 endif
 
 ifdef CONFIG_DEBUG_INFO_REDUCED
@@ -1072,7 +1072,7 @@ ifdef CONFIG_MODULE_COMPRESS
     mod_compress_cmd = $(KGZIP) -n -f
   endif # CONFIG_MODULE_COMPRESS_GZIP
   ifdef CONFIG_MODULE_COMPRESS_XZ
-    mod_compress_cmd = $(XZ) -f
+    mod_compress_cmd = $(XZ) --lzma2=dict=2MiB -f
   endif # CONFIG_MODULE_COMPRESS_XZ
 endif # CONFIG_MODULE_COMPRESS
 export mod_compress_cmd
@@ -1123,6 +1123,7 @@ endif # CONFIG_BPF
 
 PHONY += prepare0
 
+extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
 export MODORDER := $(extmod-prefix)modules.order
 export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps
 
@@ -1280,14 +1281,22 @@ define filechk_utsrelease.h
 endef
 
 define filechk_version.h
-	echo \#define LINUX_VERSION_CODE $(shell                         \
-	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
-	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
+	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
+		echo \#define LINUX_VERSION_CODE $(shell                 \
+		expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 255); \
+	else                                                             \
+		echo \#define LINUX_VERSION_CODE $(shell                 \
+		expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
+	fi;                                                              \
+	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
+	((c) > 255 ? 255 : (c)))';                                       \
+	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
+	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
+	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
 endef
 
 $(version_h): FORCE
 	$(call filechk,version.h)
-	$(Q)rm -f $(old_version_h)
 
 include/generated/utsrelease.h: include/config/kernel.release FORCE
 	$(call filechk,utsrelease.h)