[libcxx-commits] [libcxx] [libc++] LWG4324: `unique_ptr<void>::operator*` is not SFINAE-friendly (PR #190919)

Sat May 9 12:01:03 PDT 2026

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-riscv-rva23-zvl1024b-2stage` running on `rise-worker-3` while building `libcxx` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/213/builds/2975

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 4 (annotate) failure: '../llvm-zorg/zorg/buildbot/builders/annotated/rise-riscv-build.sh --jobs=32' (failure)
...
@@@@@@@@@@ Pivoting execution to qemu-system @@@@@@@@
About to execute qemu command: qemu-system-riscv64 -machine virt -cpu rva23s64,vlen=1024,rvv_ta_all_1s=true,rvv_ma_all_1s=true,rvv_vl_half_avl=true -smp 32 -m 64G -device virtio-blk-device,drive=hd -drive file=/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../rootfs.img,if=none,id=hd,format=raw -virtfs local,path=hgcomm,mount_tag=hgcomm,security_model=none,id=hgcomm -device virtio-blk-device,drive=hdb -drive file=llvm-project.img,format=raw,if=none,id=hdb -bios /usr/share/qemu/opensbi-riscv64-generic-fw_dynamic.bin -kernel /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../kernel -initrd /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../initrd -object rng-random,filename=/dev/urandom,id=rng -device virtio-rng-device,rng=rng -nographic -append rw quiet root=/dev/vda console=ttyS0
Traceback (most recent call last):
  File "/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/llvm-zorg/buildbot/riscv-rise/lit-on-qemu", line 145, in <module>
    subprocess.run(qemu_command, check=True)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/subprocess.py", line 577, in run
    raise CalledProcessError(retcode, process.args,
                             output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['qemu-system-riscv64', '-machine', 'virt', '-cpu', 'rva23s64,vlen=1024,rvv_ta_all_1s=true,rvv_ma_all_1s=true,rvv_vl_half_avl=true', '-smp', '32', '-m', '64G', '-device', 'virtio-blk-device,drive=hd', '-drive', 'file=/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../rootfs.img,if=none,id=hd,format=raw', '-virtfs', 'local,path=hgcomm,mount_tag=hgcomm,security_model=none,id=hgcomm', '-device', 'virtio-blk-device,drive=hdb', '-drive', 'file=llvm-project.img,format=raw,if=none,id=hdb', '-bios', '/usr/share/qemu/opensbi-riscv64-generic-fw_dynamic.bin', '-kernel', '/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../kernel', '-initrd', '/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../initrd', '-object', 'rng-random,filename=/dev/urandom,id=rng', '-device', 'virtio-rng-device,rng=rng', '-nographic', '-append', 'rw quiet root=/dev/vda console=ttyS0']' died with <Signals.SIGSEGV: 11>.
FAILED: CMakeFiles/check-all /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/CMakeFiles/check-all 
cd /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2 && /usr/bin/python3 /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/llvm-zorg/buildbot/riscv-rise/lit-on-qemu -v /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/utils/mlgo-utils /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/lld/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/include-cleaner/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/clangd/test/../unittests /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/clangd/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/utils/lit /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/test
ninja: build stopped: subcommand failed.
Step 11 (llvm-project check-all) failure: llvm-project check-all (failure)
...
@@@@@@@@@@ Pivoting execution to qemu-system @@@@@@@@
About to execute qemu command: qemu-system-riscv64 -machine virt -cpu rva23s64,vlen=1024,rvv_ta_all_1s=true,rvv_ma_all_1s=true,rvv_vl_half_avl=true -smp 32 -m 64G -device virtio-blk-device,drive=hd -drive file=/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../rootfs.img,if=none,id=hd,format=raw -virtfs local,path=hgcomm,mount_tag=hgcomm,security_model=none,id=hgcomm -device virtio-blk-device,drive=hdb -drive file=llvm-project.img,format=raw,if=none,id=hdb -bios /usr/share/qemu/opensbi-riscv64-generic-fw_dynamic.bin -kernel /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../kernel -initrd /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../initrd -object rng-random,filename=/dev/urandom,id=rng -device virtio-rng-device,rng=rng -nographic -append rw quiet root=/dev/vda console=ttyS0
Traceback (most recent call last):
  File "/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/llvm-zorg/buildbot/riscv-rise/lit-on-qemu", line 145, in <module>
    subprocess.run(qemu_command, check=True)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/subprocess.py", line 577, in run
    raise CalledProcessError(retcode, process.args,
                             output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['qemu-system-riscv64', '-machine', 'virt', '-cpu', 'rva23s64,vlen=1024,rvv_ta_all_1s=true,rvv_ma_all_1s=true,rvv_vl_half_avl=true', '-smp', '32', '-m', '64G', '-device', 'virtio-blk-device,drive=hd', '-drive', 'file=/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../rootfs.img,if=none,id=hd,format=raw', '-virtfs', 'local,path=hgcomm,mount_tag=hgcomm,security_model=none,id=hgcomm', '-device', 'virtio-blk-device,drive=hdb', '-drive', 'file=llvm-project.img,format=raw,if=none,id=hdb', '-bios', '/usr/share/qemu/opensbi-riscv64-generic-fw_dynamic.bin', '-kernel', '/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../kernel', '-initrd', '/home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/../initrd', '-object', 'rng-random,filename=/dev/urandom,id=rng', '-device', 'virtio-rng-device,rng=rng', '-nographic', '-append', 'rw quiet root=/dev/vda console=ttyS0']' died with <Signals.SIGSEGV: 11>.
FAILED: CMakeFiles/check-all /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/CMakeFiles/check-all 
cd /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2 && /usr/bin/python3 /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/llvm-zorg/buildbot/riscv-rise/lit-on-qemu -v /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/utils/mlgo-utils /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/lld/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/include-cleaner/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/clangd/test/../unittests /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/clangd/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/tools/extra/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/tools/clang/test /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/utils/lit /home/buildbot-worker/bbroot/clang-riscv-rva23-zvl1024b-2stage/stage2/test
ninja: build stopped: subcommand failed.
program finished with exit code 1
elapsedTime=2468.448061

```

</details>

https://github.com/llvm/llvm-project/pull/190919