"wasm32-wasi 3.x" buildbot times out on building Python

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Bug report

The wasm32-wasi 3.x buildbot worker seems to be affected by this LLVM (clang) performance issue: llvm/llvm-project#179695. Sometimes, the "Compile build Python" step is killed by a timeout.

Example of failure: the "Compile build Python" times out after 35 minutes 10 seconds.

clang -shared      Modules/pyexpat.o -lm Modules/expat/libexpat.a  -o Modules/pyexpat.cpython-316d-x86_64-linux-gnu.so
clang -shared      Modules/_elementtree.o   -o Modules/_elementtree.cpython-316d-x86_64-linux-gnu.so

command timed out: 1200 seconds without output running [b'python3', b'Tools/wasm/wasi.py', b'make-build-python'], attempting to kill
process killed by signal 9
program finished with exit code -1

"Compile build Python" uses clang -Og.

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cc @brettcannon

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I wrote cpython-devcontainers PRs to upgrade Fedora from 43 to 44, but stick to LLVM 21:

• Bump to Fedora 44 with LLVM 22 cpython-devcontainers#81
• Use LLVM 21 for the CPython JIT compiler cpython-devcontainers#82

[brettcannon]

It might also be the buildbot itself. A relaunch of the buildbot container got it to completion, but perf is still bad. I'll try a reboot after the 3.15.0b3 release.