Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

- Add HOSTPKG_CONFIG env variable to allow users to overr

Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

- Add HOSTPKG_CONFIG env variable to allow users to override pkg-config

- Support W=e as a shorthand for KCFLAGS=-Werror

- Fix CONFIG_IKHEADERS build to support toybox cpio

- Add scripts/dummy-tools/pahole to ease distro packagers' life

- Suppress false-positive warnings from checksyscalls.sh for W=2 build

- Factor out the common code of arch/*/boot/install.sh into
scripts/install.sh

- Support 'kernel-install' tool in scripts/prune-kernel

- Refactor module-versioning to link the symbol versions at the final
link of vmlinux and modules

- Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in
an arch-agnostic way

- Refactor modpost, Makefiles

* tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits)
genksyms: adjust the output format to modpost
kbuild: stop merging *.symversions
kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
modpost: extract symbol versions from *.cmd files
modpost: add sym_find_with_module() helper
modpost: change the license of EXPORT_SYMBOL to bool type
modpost: remove left-over cross_compile declaration
kbuild: record symbol versions in *.cmd files
kbuild: generate a list of objects in vmlinux
modpost: move *.mod.c generation to write_mod_c_files()
modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header
scripts/prune-kernel: Use kernel-install if available
kbuild: factor out the common installation code into scripts/install.sh
modpost: split new_symbol() to symbol allocation and hash table addition
modpost: make sym_add_exported() always allocate a new symbol
modpost: make multiple export error
modpost: dump Module.symvers in the same order of modules.order
modpost: traverse the namespace_list in order
modpost: use doubly linked list for dump_lists
modpost: traverse unresolved symbols in order
...

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kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS

include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
as a placeholder.

Genksyms writes the version CRCs into t

kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS

include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
as a placeholder.

Genksyms writes the version CRCs into the linker script, which will be
used for filling the __crc_* symbols. The linker script format depends
on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset
to the reference of CRC.

It is time to get rid of this complexity.

Now that modpost parses text files (.*.cmd) to collect all the CRCs,
it can generate C code that will be linked to the vmlinux or modules.

Generate a new C file, .vmlinux.export.c, which contains the CRCs of
symbols exported by vmlinux. It is compiled and linked to vmlinux in
scripts/link-vmlinux.sh.

Put the CRCs of symbols exported by modules into the existing *.mod.c
files. No additional build step is needed for modules. As before,
*.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.

No linker magic is used here. The new C implementation works in the
same way, whether CONFIG_RELOCATABLE is enabled or not.
CONFIG_MODULE_REL_CRCS is no longer needed.

Previously, Kbuild invoked additional $(LD) to update the CRCs in
objects, but this step is unneeded too.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)

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