clang++ --print-file-name is no longer functional

[redvers]

Describe the bug

The command-line flag '--print-file-name` should return the full path to the wanted file.

Working example:

[nix-shell:~]$ clang++ --print-file-name='libstdc++.a'
/nix/store/sxdx80lmk4zkhb51f4x5dgqvxgmx55wl-gcc-11.3.0/lib64/gcc/x86_64-unknown-linux-gnu/11.3.0/../../../../lib64/libstdc++.a

This is used in some build systems (including ponyc which is broken and I am currently trying to fix).

Steps To Reproduce

On master, note no path provided:

[nix-shell:~/projects]$ clang++ --print-file-name=libstdc++.a
libstdc++.a

Expected behavior

The correct path should be returned:

[nix-shell:~]$ clang++ --print-file-name='libstdc++.a'
/nix/store/sxdx80lmk4zkhb51f4x5dgqvxgmx55wl-gcc-11.3.0/lib64/gcc/x86_64-unknown-linux-gnu/11.3.0/../../../../lib64/libstdc++.a

Notify maintainers

llvm team: @Ericson2314 @sternenseemann @lovek323 @dtzWill @primeos

Metadata

[red@blimpofevil:~]$ nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 5.15.91, NixOS, 23.05 (Stoat), 23.05pre451105.06999209d7a`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.13.2`
 - channels(root): `"nixos"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`

I have a machine that was last updated from master on Jan 2nd (3302bc3) which is functional. I'm starting to bisect, I'll update if/when I find the commit that broke it.

Thanks.

[redvers]

Okay, the commit that breaks it is:

commit e4957a85c9db87ed5124310dfbb5f4c9886c1b75
Merge: 7f299adbdd1 66bb8338fc1
Author: Vladimír Čunát <v@cunat.cz>
Date:   Tue Jan 31 09:42:28 2023 +0100

    Merge #211923: staging-next 2023-01-21

[red@blimpofevil:~/projects/nixpkgs]$ git checkout 7f299adbdd1cb798a3639350c8cba6bdeab7ab53
Previous HEAD position was e4957a85c9d Merge #211923: staging-next 2023-01-21
HEAD is now at 7f299adbdd1 Merge pull request #213689 from r-ryantm/auto-update/azure-storage-azcopy

[red@blimpofevil:~/projects/nixpkgs]$ nix-shell -I nixpkgs=. -p clang_11

[nix-shell:~/projects/nixpkgs]$ clang++ --print-file-name='libstdc++.a'
/nix/store/z1yw9cw97bcdfmxz5wk7j1bycw42r1mw-gcc-11.3.0/lib64/gcc/x86_64-unknown-linux-gnu/11.3.0/../../../../lib64/libstdc++.a
[nix-shell:~/projects/nixpkgs]$ git checkout e4957a85c9db87ed5124310dfbb5f4c9886c1b75
Previous HEAD position was 7f299adbdd1 Merge pull request #213689 from r-ryantm/auto-update/azure-storage-azcopy
HEAD is now at e4957a85c9d Merge #211923: staging-next 2023-01-21

[nix-shell:~/projects/nixpkgs]$ 
exit

[red@blimpofevil:~/projects/nixpkgs]$ nix-shell -I nixpkgs=. -p clang_11

[nix-shell:~/projects/nixpkgs]$ clang++ --print-file-name='libstdc++.a'
libstdc++.a

[redvers]

Bisecting the staging-next branch…

[redvers]

Looks like it will be fixed after this hits master:

#213185

[redvers]

This was fixed by #214010