Build failure: compiler-rt-libc on x86_64-darwin

[mio-19]

Nixpkgs version

• Unstable (26.05)

Steps to reproduce

try to build telegram-desktop or materialgram which depend on tg_owt which depend on compiler-rt-libc

or build shell-gpt

Can Hydra reproduce this build failure?

Please select the Hydra Status.

Link to Hydra build job

I don't know how to search on hydra

Relevant log output

RTUbsan.osx.dir/ubsan_type_hash.cpp.o lib/ubsan/CMakeFiles/RTUbsan.osx.dir/ubsan_type_hash_itanium.cpp.o lib/ubsan/CMakeFiles/RTUbsan.osx.dir/ubsan_type_hash_win.cpp.o   && :
2026-01-16T21:35:48.9614740Z        > Warning: supplying the --target x86_64-apple-macos != x86_64-apple-darwin argument to a nix-wrapped compiler may not work correctly - cc-wrapper is currently not designed with multi-target compilers in mind. You may want to use an un-wrapped compiler instead.
2026-01-16T21:35:48.9617740Z        > ld: warning: changing Mac Catalyst minOS version from 13.1 to 17.0
2026-01-16T21:35:48.9618700Z        > ld: -sdk_version may not be used for zippered binaries
2026-01-16T21:35:48.9619800Z        > clang++: error: linker command failed with exit code 1 (use -v to see invocation)
2026-01-16T21:35:48.9620870Z        > ninja: build stopped: subcommand failed.
2026-01-16T21:35:48.9621480Z        For full logs, run:
2026-01-16T21:35:48.9622350Z          nix log /nix/store/fcbmzh97v6baypqn7bj8vx1b3d0pdrv3-compiler-rt-libc-19.1.7.drv
2026-01-16T21:35:48.9624290Z error: Cannot build '/nix/store/wy31wk4drwabrmhgbyh47g1ws7yccq4x-clang-wrapper-19.1.7.drv'.
2026-01-16T21:35:48.9625390Z        Reason: 1 dependency failed.
2026-01-16T21:35:48.9625920Z        Output paths:
2026-01-16T21:35:48.9626590Z          /nix/store/6n3skncx5ihhxd5cjzympd4v6p68n2vc-clang-wrapper-19.1.7
2026-01-16T21:35:48.9628140Z error: Build failed due to failed dependency
2026-01-16T21:35:48.9629130Z error: Cannot build '/nix/store/mij24dc337782lffck53yj6yxqdwhxvv-stdenv-darwin.drv'.
2026-01-16T21:35:48.9630120Z        Reason: 1 dependency failed.
2026-01-16T21:35:48.9630640Z        Output paths:
2026-01-16T21:35:48.9631230Z          /nix/store/chvwqcg47h38vw55wf82af0m90ml49sb-stdenv-darwin
2026-01-16T21:35:48.9632030Z error: Build failed due to failed dependency
2026-01-16T21:35:48.9633170Z error: Cannot build '/nix/store/izx210mifdq95bc9wyai9a4psp6z8isj-tg_owt-0-unstable-2025-06-02.drv'.
2026-01-16T21:35:48.9634330Z        Reason: 1 dependency failed.
2026-01-16T21:35:48.9634850Z        Output paths:
2026-01-16T21:35:48.9635620Z          /nix/store/6v26piz9akik5g5r6pqaacd8p7h137b2-tg_owt-0-unstable-2025-06-02-dev
2026-01-16T21:35:48.9636900Z          /nix/store/dpd36pmp239brn3hvyann1bcd7przz86-tg_owt-0-unstable-2025-06-02
2026-01-16T21:35:48.9637880Z error: Build failed due to failed dependency

Additional context

No response

System metadata

TODO

Notify maintainers

@RossComputerGuy @alyssais @Ericson2314 @emilazy @lovek323 @rrbutani @sternenseemann

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[mio-19]

Also broken on aarch64-darwin

[quasi-coherent]

Any update on this?

[MacDefender]

While trying to update my nix-darwin today I also run into errors with compiler-rt-libc-18.1.8 on aarch64-darwin:
error: no matching function for call to '__countl_zero'
error: no matching function for call to '__countr_zero'
error: use of undeclared identifier '__builtin_ctzg'

[wattmto]

#523142 might fix this.

[karldelandsheere]

Same as you all but on aarch64-darwin. Makes it impossible to install/update Bitwarden Desktop for me.