fix(linux): link libpthread alongside mimalloc.o#6435
Merged
FeodorFitsner merged 2 commits intorelease/v0.85.0from Apr 23, 2026
Merged
fix(linux): link libpthread alongside mimalloc.o#6435FeodorFitsner merged 2 commits intorelease/v0.85.0from
FeodorFitsner merged 2 commits intorelease/v0.85.0from
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Flutter's build UI swallows the actual ld stderr, leaving only a bare "clang: error: linker command failed with exit code 1" in CI logs. Temporary instrumentation to reveal what's failing: - flutter build linux --verbose to propagate cmake/ld output. - message(NOTICE ...) to dump MIMALLOC_LIB value and existence check. - LINKER:--verbose to emit ld's full invocation and error detail. To be reverted once the root cause is pinned down.
The Linux client has been failing to link on every distro since mimalloc was actually wired up (#6416): `mimalloc.o` references `pthread_setspecific` but `ld --as-needed` (default on Ubuntu 20.04+) won't pull `libpthread` in transitively through other DSOs, so the final link aborts with: undefined reference to symbol 'pthread_setspecific@@GLIBC_2.2.5' libpthread.so.0: error adding symbols: DSO missing from command line Pair the mimalloc link with `Threads::Threads` so libpthread is explicitly on the link line. Applied to both the client `CMakeLists.txt` and the `flet build linux` build template so end users don't hit this. Also revert the temporary diagnostic instrumentation added to surface the real linker error.
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Summary
mimalloc.ousespthread_setspecific; withld --as-needed(default on Ubuntu 20.04+), libpthread won't be pulled in transitively and the final link aborts withundefined reference to symbol 'pthread_setspecific@@GLIBC_2.2.5'/libpthread.so.0: error adding symbols: DSO missing from command line.Threads::Threadsin both client/linux/CMakeLists.txt and theflet build linuxtemplate so libpthread is explicitly on the link line.Investigation
Flutter's build UI swallows
ldstderr, leaving only a bareclang: error: linker command failed with exit code 1in CI. I pushed a temporary diagnostic commit (reverted in this branch) that addedflutter build linux --verbose,LINKER:--verbose, andmessage(NOTICE ...)dumps forMIMALLOC_LIB. The diagnostic run (https://github.com/flet-dev/flet/actions/runs/24813135717) confirmed the undefined-symbol failure.Test plan
Summary by Sourcery
Ensure Linux client binaries explicitly link pthread when mimalloc is enabled to fix linker failures on modern distributions.
Build: