# git rev-parse -q --verify a2818e1225b055e1aab14e47a4ce039338b0c216^{commit}
# git fetch -q -n -f git://gitlab.ozlabs.ibm.com/mirror/linux-kbuild.git for-next
warning: The last gc run reported the following. Please correct the root cause
and remove .git/gc.log.
Automatic cleanup will not be performed until the file is removed.

warning: There are too many unreachable loose objects; run 'git prune' to remove them.

# git rev-parse -q --verify a2818e1225b055e1aab14e47a4ce039338b0c216^{commit}
a2818e1225b055e1aab14e47a4ce039338b0c216
# git checkout -q -f -B kisskb a2818e1225b055e1aab14e47a4ce039338b0c216
# git clean -qxdf
# < git log -1
# commit a2818e1225b055e1aab14e47a4ce039338b0c216
# Author: Alexey Kardashevskiy <aik@ozlabs.ru>
# Date:   Thu Sep 29 12:08:23 2022 +1000
# 
#     zstd: Fixing mixed module-builtin objects
#     
#     With CONFIG_ZSTD_COMPRESS=m and CONFIG_ZSTD_DECOMPRESS=y we end up in
#     a situation when files from lib/zstd/common/ are compiled once to be
#     linked later for ZSTD_DECOMPRESS (build-in) and ZSTD_COMPRESS (module)
#     even though CFLAGS are different for builtins and modules.
#     So far somehow this was not a problem but enabling LLVM LTO exposes
#     the problem as:
#     
#     ld.lld: error: linking module flags 'Code Model': IDs have conflicting values in 'lib/built-in.a(zstd_common.o at 5868)' and 'ld-temp.o'
#     
#     This particular conflict is caused by KBUILD_CFLAGS=-mcmodel=medium vs.
#     KBUILD_CFLAGS_MODULE=-mcmodel=large , modules use the large model on
#     POWERPC as explained at
#     https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/Makefile?h=v5.18-rc4#n127
#     but the current use of common files is wrong anyway.
#     
#     This works around the issue by introducing a zstd_common module with
#     shared code.
#     
#     Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
#     Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-ld --version
# < git log --format=%s --max-count=1 a2818e1225b055e1aab14e47a4ce039338b0c216
# < make -s -j 48 ARCH=m68k O=/kisskb/build/kbuild_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  defconfig
# < make -s -j 48 ARCH=m68k O=/kisskb/build/kbuild_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  help
# make -s -j 48 ARCH=m68k O=/kisskb/build/kbuild_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  olddefconfig
# make -s -j 48 ARCH=m68k O=/kisskb/build/kbuild_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  
Completed OK
# rm -rf /kisskb/build/kbuild_m68k-defconfig_m68k-gcc8
# Build took: 0:02:52.615086