# git rev-parse -q --verify e5d523f1ae8f2cef01f8e071aeee432654166708^{commit}
e5d523f1ae8f2cef01f8e071aeee432654166708
already have revision, skipping fetch
# git checkout -q -f -B kisskb e5d523f1ae8f2cef01f8e071aeee432654166708
# git clean -qxdf
# < git log -1
# commit e5d523f1ae8f2cef01f8e071aeee432654166708
# Author: Nick Desaulniers <ndesaulniers@google.com>
# Date:   Thu Jul 14 13:56:43 2022 -0700
# 
#     ubsan: disable UBSAN_DIV_ZERO for clang
#     
#     Building with UBSAN_DIV_ZERO with clang produces numerous fallthrough
#     warnings from objtool.
#     
#     In the case of uncheck division, UBSAN_DIV_ZERO may introduce new
#     control flow to check for division by zero.
#     
#     Because the result of the division is undefined, LLVM may optimize the
#     control flow such that after the call to __ubsan_handle_divrem_overflow
#     doesn't matter.  If panic_on_warn was set,
#     __ubsan_handle_divrem_overflow would panic.
#     
#     The problem is is that panic_on_warn is run time configurable.  If it's
#     disabled, then we cannot guarantee that we will be able to recover
#     safely.  Disable this config for clang until we can come up with a
#     solution in LLVM.
#     
#     Link: https://github.com/ClangBuiltLinux/linux/issues/1657
#     Link: https://github.com/llvm/llvm-project/issues/56289
#     Link: https://lore.kernel.org/lkml/CAHk-=wj1qhf7y3VNACEexyp5EbkNpdcu_542k-xZpzmYLOjiCg@mail.gmail.com/
#     Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
#     Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
#     Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
#     Acked-by: Nathan Chancellor <nathan@kernel.org>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-gcc --version
# < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-ld --version
# < git log --format=%s --max-count=1 e5d523f1ae8f2cef01f8e071aeee432654166708
# < make -s -j 32 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 defconfig
# < make -s -j 32 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 help
# make -s -j 32 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 olddefconfig
# make -s -j 32 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 
arch/x86/um/../kernel/module.o: In function `module_finalize':
module.c:(.text+0x434): undefined reference to `apply_returns'
collect2: error: ld returned 1 exit status
make[1]: *** [/kisskb/src/Makefile:1164: vmlinux] Error 1
make: *** [Makefile:219: __sub-make] Error 2
Command 'make -s -j 32 ARCH=um O=/kisskb/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 ' returned non-zero exit status 2
# rm -rf /kisskb/build/linus_um-defconfig_um-x86_64
# Build took: 0:00:28.972961