Backport 801b519dfd01 ("[sanitizer_common] Fix build on ppc64+musl (#120036)") to LLVM 20

[ziyao233]

As described in the original commit, not only ppc64 but also riscv64 and mips platforms were affected by the missing guard, causing errors like,

[1/10] Building CXX object lib/sanitiz...cv64.dir/sanitizer_linux_libcdep.cpp.o
FAILED: lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o 
/usr/sbin/riscv64-unknown-linux-musl-clang++ --target=riscv64-unknown-linux-musl -DHAVE_RPC_XDR_H=0 -D__func__=__FUNCTION__ -I/root/Source/llvm-project/compiler-rt/lib/sanitizer_common/.. -std=c++17 -O3 -MD -MT lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o -MF lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o.d -o lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o -c /root/Source/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
/root/Source/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp:627:29: error: use of undeclared identifier 'TlsPreTcbSize'
  627 |   const uptr pre_tcb_size = TlsPreTcbSize();
      |                             ^
1 error generated.
[2/10] Building CXX object lib/sanitiz...cv64.dir/sanitizer_linux_libcdep.cpp.o

when building compiler-rt for riscv64-unknown-linux-musl platforms.

I've tested the referred patch does fix the problem and could be applied cleanly to branch release/20.x.

[llvmbot]

@llvm/issue-subscribers-backend-powerpc

Author: Yao Zi (ziyao233)

As described in the original commit, not only ppc64 but also riscv64 and mips platforms were affected by the missing guard, causing errors like,

[1/10] Building CXX object lib/sanitiz...cv64.dir/sanitizer_linux_libcdep.cpp.o
FAILED: lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o 
/usr/sbin/riscv64-unknown-linux-musl-clang++ --target=riscv64-unknown-linux-musl -DHAVE_RPC_XDR_H=0 -D__func__=__FUNCTION__ -I/root/Source/llvm-project/compiler-rt/lib/sanitizer_common/.. -std=c++17 -O3 -MD -MT lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o -MF lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o.d -o lib/sanitizer_common/CMakeFiles/RTSanitizerCommonLibc.riscv64.dir/sanitizer_linux_libcdep.cpp.o -c /root/Source/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
/root/Source/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp:627:29: error: use of undeclared identifier 'TlsPreTcbSize'
  627 |   const uptr pre_tcb_size = TlsPreTcbSize();
      |                             ^
1 error generated.
[2/10] Building CXX object lib/sanitiz...cv64.dir/sanitizer_linux_libcdep.cpp.o

when building compiler-rt for riscv64-unknown-linux-musl platforms.

I've tested the referred patch does fix the problem and could be applied cleanly to branch release/20.x.

[ziyao233]

Could anyone please add a milestone for the issue? Then I could create a cherry-picked PR with llvmbot for it. Thanks.

[ziyao233]

/cherry-pick 801b519

[brad0]

/cherry-pick 801b519

[ziyao233]

Is the workflow broken? Both trials failed with 'fatal: could not read Password for 'https://***@github.com': No such device or address' error.

https://github.com/llvm/llvm-project/actions/runs/14828077703/job/41624236406#step:4:40
https://github.com/llvm/llvm-project/actions/runs/14828214885/job/41624569454#step:4:40