Source: mesa Severity: important Justification: causes FTBFS in at least src:gtk4 Tags: ftbfs X-Debbugs-Cc: g...@packages.debian.org, debian-ri...@packages.debian.org, debian-loonga...@packages.debian.org, debian-m...@packages.debian.org User: debian-m...@packages.debian.org Usertags: mips64el User: debian-ri...@packages.debian.org Usertags: riscv64
Historically, Mesa's llvmpipe used LLVM MCJIT, which supports a limited range of architectures and will not add more, and this resulted in several architectures having either a broken llvmpipe or no llvmpipe support at all. With the recent upload of Mesa 24.2.x to unstable, llvmpipe now uses ORCJIT for architectures where MCJIT is unavailable. However, the ORCJIT version of llvmpipe doesn't seem to be particularly mature yet (perhaps unsurprisingly, it's very new!) and is crashing under some circumstances on at least riscv64: #1080435. If softpipe was still enabled on at least the affected architectures, then packages' test suites would be able to force its use via GALLIUM_DRIVER=softpipe in the environment if necessary. At the moment src:gtk4 does this on mips*, plus the powerpc and sparc* -ports architectures, to avoid #1010838; the removal of the softpipe driver means that this makes GL initialization fail, causing test failures and a FTBFS (I'll report this as a separate RC bug in src:gtk4). I had hoped to do the same for riscv64 to work around #1080435, but in fact this is not possible for the same reason. While it's more important on the ORCJIT architectures, also enabling softpipe on more mainstream architectures like x86 would make it easier for maintainers to compare llvmpipe with softpipe (without having to build their package on porterboxes that are often very slow), and easier to get a consistent test result for all architectures. For what it's worth, the upstream default (with -Dgallium-drivers=auto) is to enable softpipe on all architectures. In the Debian packaging, I believe this would be most easily done by reverting 1ba4b2499e875266f6fbd7ba20068fb569986286 "rules: Build softpipe or llvmpipe depending on the arch, not both.". Thanks, smcv