$ make -skj"$(nproc)" ARCH=um LLVM=1 mrproper defconfig linux
...
WARNING: modpost: vmlinux.o(__ex_table+0x0): Section mismatch in reference from the (unknown reference) (unknown) to the (unknown reference) .ltext:(unknown)
The relocation at __ex_table+0x0 references
section ".ltext" which is not in the list of
authorized sections.  If you're adding a new section
and/or if this reference is valid, add ".ltext" to the
list of authorized sections to jump to on fault.
This can be achieved by adding ".ltext" to
OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.
WARNING: modpost: vmlinux.o(__ex_table+0x4): Section mismatch in reference from the (unknown reference) (unknown) to the (unknown reference) .ltext:(unknown)
The relocation at __ex_table+0x4 references
section ".ltext" which is not in the list of
authorized sections.  If you're adding a new section
and/or if this reference is valid, add ".ltext" to the
list of authorized sections to jump to on fault.
This can be achieved by adding ".ltext" to
OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.
...
/usr/sbin/ld: init/calibrate.o: relocation R_X86_64_32 against `.data' can not be used when making a PIE object; recompile with -fPIE
/usr/sbin/ld: failed to set dynamic section sizes: bad value
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[3]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
...

# bad: [f1156fb622a73bcf1623c9bebfb6a638b097af14] [AMDGPU][IGLP]: Add SchedGroupMask::TRANS (#75416)
# good: [065796bb9293b222fa3d63311af542a98b96d09a] [clang][OpenMP] Fix missing DI for __kmpc_global_thread_num (#73856)
git bisect start 'f1156fb622a73bcf1623c9bebfb6a638b097af14' '065796bb9293b222fa3d63311af542a98b96d09a'
# good: [774295ca1d5ff752cb478b61f22a5b1dbe33074f] [libc++][test] Fix MSVC warnings with `static_cast`s (#74962)
git bisect good 774295ca1d5ff752cb478b61f22a5b1dbe33074f
# good: [2ab926d959613e677458a818e9e42344ab4fd8c2] [flang][MLIR][OpenMP] Add support for `target update` directive. (#75047)
git bisect good 2ab926d959613e677458a818e9e42344ab4fd8c2
# bad: [a3952b4f022ce03c778ecc3b44ffff350b512735] [Analysis] Remove unused forward declarations (NFC)
git bisect bad a3952b4f022ce03c778ecc3b44ffff350b512735
# bad: [c1a6974d6b3dc7be2178d8db9f8fc6c2cc9230f2] [AMDGPU][MC] Add GFX12 SMEM encoding (#75215)
git bisect bad c1a6974d6b3dc7be2178d8db9f8fc6c2cc9230f2
# bad: [3194928c3cfa6623c5de78ae7ab2ab7ab0cf0232] [llvm-exegesis] Refactor MMAP platform-specific preprocessor directives (#75422)
git bisect bad 3194928c3cfa6623c5de78ae7ab2ab7ab0cf0232
# good: [1b531d54f6234488dec048fec1c5aca331bf8f3d] [InstrRef][nfc] Remove usage of unique_ptrs of arrays (#74203)
git bisect good 1b531d54f6234488dec048fec1c5aca331bf8f3d
# good: [5bc1adff69315dcef670e9fcbe04067b5d5963fb] Revert "lldb: Cache string hash during ConstString pool queries/insertions"
git bisect good 5bc1adff69315dcef670e9fcbe04067b5d5963fb
# bad: [0544c781728a665806b069cb8202acd4f6981a0a] Fix a crash from character type confusion interaction with libedit (#75388)
git bisect bad 0544c781728a665806b069cb8202acd4f6981a0a
# bad: [7bc6c4abe8e8d8ab70e02e4c2025a94dda01d908] [mlir][print]Add functions for printing memref f16/bf16/i16 (#75094)
git bisect bad 7bc6c4abe8e8d8ab70e02e4c2025a94dda01d908
# bad: [ec92d74a0ef89b9dd46aee6ec8aca6bfd3c66a54] Reland [X86] Respect code models more when determining if a global reference can fit in 32 bits (#75386)
git bisect bad ec92d74a0ef89b9dd46aee6ec8aca6bfd3c66a54
# good: [f976719fb2cb23364957e5993f7fc3684ee15391] Revert "[ADT][StringMap] Add ability to precompute and reuse the string hash"
git bisect good f976719fb2cb23364957e5993f7fc3684ee15391
# first bad commit: [ec92d74a0ef89b9dd46aee6ec8aca6bfd3c66a54] Reland [X86] Respect code models more when determining if a global reference can fit in 32 bits (#75386)