gh-154701: prevent executor self-links in JIT cold exits - #155323
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cocolato wants to merge 3 commits into
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gh-154701: prevent executor self-links in JIT cold exits#155323cocolato wants to merge 3 commits into
cocolato wants to merge 3 commits into
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Fidget-Spinner
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Aug 7, 2026
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Awesome, thanks so much!
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cpython/Python/optimizer_bytecodes.c
Lines 1468 to 1471 in e469fa9
After the
FOR_ITERguard fails, the side exit targets the same bytecode location where the current executor is installed._COLD_EXITthen links that exit back to the current executor itself, creating a self-loop that can never make forward progress.Detach the self-linked executor and restore the original bytecode before falling back to Tier 1 can solve this issue.