Bug#1081947: libgl1-mesa-dri: llvmpipe exists but does not work on powerpc

I currently do not have a powerpc machine to test,but I could test it using QEMU's powerpc emulation.

And for those who don't know softpipe and LLVMPipe (unlikely)

Softpipe:Software rasterizer with no LLVM,compliant with OpenGL 3.3,slow

LLVMpipe:Software rasterizer accelerated with LLVM,compliant with OpenGL 4.5,fast

That's how it works.

On Mon, Sep 16, 2024 at 9:30 AM Simon McVittie <smcv@debian.org> wrote:

Source: libgl1-mesa-dri
Version: 24.2.2-1
Severity: normal
X-Debbugs-Cc: debian-powerpc@lists.debian.org
User: debian-powerpc@lists.debian.org
Usertags: powerpc

Similar to the situation on sparc64.

To reproduce:
- install gtk4 build-dependencies on powerpc porterbox with no access to a
real GPU
- get gtk4 source
- edit debian/rules to remove the special case that forces use of softpipe
on powerpc
- build and run tests

Expected result: either of these:
- llvmpipe exists, is used, and works
- llvmpipe doesn't exist and softpipe is automatically used instead

Actual result:
- all tests that use OpenGL fail with message "LLVM ERROR: Relocation
type not implemented yet!" and a SIGABRT

I would suggest special-casing llvmpipe (and anything else requiring LLVM
JIT: lavapipe?) to be built on most of the $(LLVM_ARCHS), but not powerpc.

smcv