# git rev-parse -q --verify d0ee23f9d78be5531c4b055ea424ed0b489dfe9b^{commit}
# git fetch -q -n -f git://fs.ozlabs.ibm.com/kernel/linus master
# git rev-parse -q --verify d0ee23f9d78be5531c4b055ea424ed0b489dfe9b^{commit}
d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
# git checkout -q -f -B kisskb d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
# git clean -qxdf
# < git log -1
# commit d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
# Author: Nathan Chancellor <nathan@kernel.org>
# Date:   Mon Sep 13 15:09:00 2021 -0700
# 
#     tools: compiler-gcc.h: Guard error attribute use with __has_attribute
#     
#     When building objtool with HOSTCC=clang, there are several errors along
#     the lines of
#     
#       orc_dump.c:201:28: error: unknown attribute 'error' ignored [-Werror,-Wunknown-attributes]
#     
#     This occurs after commit 4e59869aa655 ("compiler-gcc.h: drop checks for
#     older GCC versions"), which removed the GCC_VERSION gating.  The removed
#     version check just so happened to prevent __compiletime_error() from
#     being defined with clang because it pretends to be GCC 4.2.1 for
#     compatibility but the error attribute was not added to clang until
#     14.0.0.
#     
#     Commit 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h
#     mutually exclusive") and commit a3f8a30f3f00 ("Compiler Attributes: use
#     feature checks instead of version checks") refactored the handling of
#     attributes in the main kernel to avoid situations like this but that
#     refactoring has never been done for the tools directory.
#     
#     Refactoring is a rather large undertaking and this has never been an
#     issue before so instead, just guard the definition of
#     __compiletime_error() with __has_attribute() so that there are no more
#     errors.
#     
#     Fixes: 4e59869aa655 ("compiler-gcc.h: drop checks for older GCC versions")
#     Signed-off-by: Nathan Chancellor <nathan@kernel.org>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version
# < git log --format=%s --max-count=1 d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
# < make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  randconfig
# Added to kconfig CONFIG_STANDALONE=y
# Added to kconfig CONFIG_BUILD_DOCSRC=n
# Added to kconfig CONFIG_MODULE_SIG=n
# Added to kconfig CONFIG_CPU_BIG_ENDIAN=y
# Added to kconfig CONFIG_PPC64=y
# Added to kconfig CONFIG_PPC_DISABLE_WERROR=y
# Added to kconfig CONFIG_SECTION_MISMATCH_WARN_ONLY=y
# Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y
# Added to kconfig CONFIG_CC_STACKPROTECTOR_STRONG=n
# Added to kconfig CONFIG_GCC_PLUGINS=n
# Added to kconfig CONFIG_LD_HEAD_STUB_CATCH=y
# Added to kconfig CONFIG_TRIM_UNUSED_KSYMS=n
# Added to kconfig CONFIG_UBSAN=n
# < make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  help
# make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  olddefconfig
.config:5799:warning: override: reassigning to symbol STANDALONE
.config:5804:warning: override: reassigning to symbol PPC_DISABLE_WERROR
.config:5805:warning: override: reassigning to symbol SECTION_MISMATCH_WARN_ONLY
.config:5809:warning: override: reassigning to symbol LD_HEAD_STUB_CATCH
# make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
Completed OK
# rm -rf /kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc9
# Build took: 0:08:07.360560