On Thu, 16 Jan 2025, Paul Gevers wrote:
The latest version of wine failed to build on the three arm architectures. It
seems the root cause is different though depending on the architecture.
The root cause is actually the same in all of them; Wine requires Clang
for building on ARM (initially only on arm64 but these days for armhf as
well), but the Debian Wine packaging has bypassed this requirement - see
e.g.
https://salsa.debian.org/wine-team/wine/-/blob/debian13-wine09/debian/patches/arm/gcc.patch.
On older Wine versions, this may initially have seemed like it didn't
cause any problems. On Wine 7.0 and 8.0 it only caused Wine to use the
wrong ABI for vararg functions, which would only be noted if you'd try to
run an executable that contains e.g. nontrivial printf calls.
Since Wine 7.4, Wine specifically requires an arm64 PE cross compiler, not
just a compiler that supports __builtin_ms_va_list. This also didn't
really cause any direct issues in Wine 8.0, but when this requirement is
bypassed in Wine 9.0, it causes Wine to hang on startup (when running
something as simple as "wine wineboot"), see
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1100695.
Since Wine 9.2, a PE cross compiler is needed for 32 bit arm as well.
Unfortunately, in Wine 10.0, one can't just use plain Clang for fulfilling
this role, as the PE cross compiler for 32 bit arm requires more compiler
builtins functions than what Wine itself provides. Thus, one can either
use llvm-mingw (https://github.com/mstorsjo/llvm-mingw/releases) for it,
or backport a couple of commits from Wine 10.3, to supply the required
builtins for 32 bit arm.
I have tested and prepared such backports at
https://gitlab.winehq.org/mstorsjo/wine/-/commits/arm-builtins-10.0. With
that in place, it's enough to just use the Debian provided clang/lld/llvm
packages for building. See
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1100695 for a diff on
top of the packaging of Wine 9.0, that provides clang/lld/llvm when
building for arm64. The same kind of modification for armhf should fix
that case.
However for armel, the build log ends like this:
checking whether gcc supports floating point instructions... no
configure: error: The ARM target needs to support floating point
instructions.
Therefore, I believe that Wine simply won't work on Debian armel any
longer. (I don't know how much other issues you'd run into down the line,
if you'd edit out this configure check.)
// Martin
