# git rev-parse -q --verify d0ee23f9d78be5531c4b055ea424ed0b489dfe9b^{commit}
d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
already have revision, skipping fetch
# 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-4.9.4-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-gcc --version
# < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-ld --version
# < git log --format=%s --max-count=1 d0ee23f9d78be5531c4b055ea424ed0b489dfe9b
# < make -s -j 10 ARCH=arm O=/kisskb/build/linus_at91_dt_defconfig_arm-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-  at91_dt_defconfig
***
*** Compiler is too old.
***   Your GCC version:    4.9.4
***   Minimum GCC version: 5.1.0
***
scripts/Kconfig.include:44: Sorry, this compiler is not supported.
make[2]: *** [/kisskb/src/scripts/kconfig/Makefile:94: at91_dt_defconfig] Error 1
make[1]: *** [/kisskb/src/Makefile:616: at91_dt_defconfig] Error 2
make: *** [Makefile:219: __sub-make] Error 2
Command 'make -s -j 10 ARCH=arm O=/kisskb/build/linus_at91_dt_defconfig_arm-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-  at91_dt_defconfig' returned non-zero exit status 2
# rm -rf /kisskb/build/linus_at91_dt_defconfig_arm-gcc4.9
# Build took: 0:00:01.231465