libmlir-19 fails to coinstall despite it explicitly stating that
capability.

mmdebstrap --variant=apt --verbose '' /dev/null 'deb http://deb.debian.org/debian unstable main' --architectures=amd64,i386 --include=libmlir-19,libmlir-19:i386

Preparing to unpack .../35-libmlir-19_1%3a19.1.7-3_amd64.deb ...
Unpacking libmlir-19:amd64 (1:19.1.7-3) ...
dpkg: error processing archive /tmp/apt-dpkg-install-BE1hEv/35-libmlir-19_1%3a19.1.7-3_amd64.deb (--unpack):
 trying to overwrite shared '/usr/lib/llvm-19/lib/libMLIR.so.19.1', which is different from other instances of package libmlir-19:amd64
Errors were encountered while processing:
 /tmp/apt-dpkg-install-BE1hEv/35-libmlir-19_1%3a19.1.7-3_amd64.deb
E: Sub-process env returned an error code (1)

Please either move those libraries to a multiarch location or remove
"Multi-Arch: same" from the libmlir-19 binary package. Given the freeze
timing I recommend doing the latter.

Please also check other packages of llvm-toolchain-19 for violating
coinstallation properties.

Helmut

  There's a merge request that removes "Multi-Arch: same" on salsa [1]. It is
for the 20 branch though, so it would need to be applied to 19 (and 18 and 17)
as well.

  Regards,
  Arnout

[1] https://salsa.debian.org/pkg-llvm-team/llvm-toolchain/-/merge_requests/164

Control: clone -1 -2
Control: retitle -2 libmlir-18 is Multi-Arch: same but fails to coinstall
Control: reassign -2 libmlir-18 1:18.1.8-17
Control: found -2 libmlir-18 1:18.1.8-18

It looks like libmlir-18 has the same problem. Reproducer:

mmdebstrap --variant=apt --verbose '' /dev/null 'deb http://deb.debian.org/debian trixie main' --architectures=amd64,i386 --include=libmlir-18,libmlir-18:i386

or the same with trixie replaced by unstable.

https://salsa.debian.org/pkg-llvm-team/llvm-toolchain/-/merge_requests/168
is the analogous change for version 19, which might be a useful basis
for fixing version 18.

     smcv

We believe that the bug you reported is fixed in the latest version of
llvm-toolchain-18, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1104336@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Matthias Klose <doko@debian.org> (supplier of updated llvm-toolchain-18 package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Sat, 08 Nov 2025 14:36:04 +0100
Source: llvm-toolchain-18
Architecture: source
Version: 1:18.1.8-20
Distribution: unstable
Urgency: medium
Maintainer: LLVM Packaging Team <pkg-llvm-team@lists.alioth.debian.org>
Changed-By: Matthias Klose <doko@debian.org>
Closes: 1071210 1098879 1104016 1104336 1114187
Changes:
 llvm-toolchain-18 (1:18.1.8-20) unstable; urgency=medium
 .
   [ Matthias Klose ]
   * On ppc64el configure --with-long-double-format=ieee for upcoming distros.
   * Fix ftbfs with C23. Closes: #1098879, #1114187.
   * Make Ubuntu plucky, questing, resolute known distros.
   * libc++abi: Don't depend on libunwind. Closes: #1071210.
   * Remove M-A: same attribute from libmlir-*. Closes: #1104336.
   * CVE-2024-7883, issue using Arm Cortex-M Security Extensions (CMSE).
     Closes: #1104016.
   * Remove obsolete build dependencies libjsoncpp-dev and pkg-config.
     Addresses: #1093961.
   * Fix a new lintian warning for the source.
   * Backport powerpc-fix-SIGILL.diff to fix SIGILL on powerpc.
 .
   [ Gianfranco Costamagna ]
   * Cherry-pick PR: #137403, #137440 and #149140 to fix sanitizer build
     in glibc-2.42 (termio/termios issues).
Checksums-Sha1:
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 dbe2ff9d39fdec17f877f77ee5ce1dae048c65b3 173296 llvm-toolchain-18_18.1.8-20.debian.tar.xz
 19fcf24dcd08c20ce5601d3e6bcc2421342f7ad4 15016 llvm-toolchain-18_18.1.8-20_source.buildinfo
Checksums-Sha256:
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Files:
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 33508406825e028c8987fb1c7cfb03c4 173296 devel optional llvm-toolchain-18_18.1.8-20.debian.tar.xz
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