Bug#1136968: clang-22 - Need multi-arch support

[Bastian Blank]

Package: clang-22
Version: 1:22.1.5-1
Severity: normal
X-Debbugs-Cc: waldi at debian.org

The kernel team thinks about switching the Linux kernel over to building
with clang.  For the way this works we really need multi-arch support
for the compiler (and also llvm-* and lld-* packages), aka those packages
needs to be marked as Multi-Arch: foreign, so we always get a usable one.

Currently at least clang-* is not marked this way.  Also it seems this
package is currently used for two purposes:
- Provide the programs.  Those need to be m-a:foreign.
- Provide the dependencies to pull in development stuff for c, c++ and
  so standard libs.  Those need to be m-a:same.

gcc did this by introducing "gcc-for-host" packages, which via
indirection can be used via build-depends.

Bastian

-- System Information:
Debian Release: forky/sid
  APT prefers testing
  APT policy: (700, 'testing'), (500, 'unstable-debug'), (500, 'stable-updates'), (500, 'oldstable-updates'), (500, 'unstable'), (500, 'stable'), (500, 'oldstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 6.19.13+deb14-amd64 (SMP w/16 CPU threads; PREEMPT)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages clang-22 depends on:
ii  binutils                2.46-3
ii  libc6                   2.42-16
ii  libc6-dev               2.42-16
pn  libclang-common-22-dev  <none>
pn  libclang-cpp22          <none>
pn  libclang1-22            <none>
ii  libgcc-15-dev           15.2.0-17
ii  libgcc-s1               16-20260425-1
pn  libllvm22               <none>
ii  libobjc-15-dev          15.2.0-17
ii  libstdc++-15-dev        15.2.0-17
ii  libstdc++6              16-20260425-1
pn  llvm-22-linker-tools    <none>

Versions of packages clang-22 recommends:
pn  clang-tools-22  <none>
pn  llvm-22-dev     <none>
ii  python3         3.13.9-3

Versions of packages clang-22 suggests:
pn  clang-22-doc  <none>
pn  wasi-libc     <none>