Wasmtime GitHub notifications bot (Oct 03 2026 at 16:24): Wasmtime GitHub notifications bot (Oct 03 2026 at 16:24):macovedj opened PR #14516 from macovedj:fix-winch-aarch64-tail-call-sp to bytecodealliance:main:
When a function with stack arguments tail-calls a callee with no stack arguments, Winch’s AArch64 backend advances SP past the saved frame pointer before reloading it. A signal handler running between those instructions can overwrite the saved FP.
This PR computes the callee’s entry SP in a scratch register, restores FP while the old frame is still protected, and then updates SP.
Fixes #14503.
Wasmtime GitHub notifications bot (Oct 03 2026 at 16:24):macovedj requested wasmtime-compiler-reviewers for a review on PR #14516.
Wasmtime GitHub notifications bot (Oct 03 2026 at 16:24):macovedj requested cfallin for a review on PR #14516.
Wasmtime GitHub notifications bot (Oct 03 2026 at 16:24):macovedj requested wasmtime-core-reviewers for a review on PR #14516.
Wasmtime GitHub notifications bot (Oct 03 2026 at 19:35):github-actions[bot] added the label winch on PR #14516.
Wasmtime GitHub notifications bot (Oct 03 2026 at 19:36):github-actions[bot] commented on PR #14516:
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Wasmtime GitHub notifications bot (Oct 04 2026 at 21:17)::memo: saulecabrera submitted PR review.
Wasmtime GitHub notifications bot (Oct 04 2026 at 21:17)::speech_balloon: saulecabrera created PR review comment:
I believe most of this code has a lot of commonalities with the one defined in
with_tail_call_resize? I wonder if we can add a small helper to avoid duplicating this and more importantly to avoid it drifting?
Wasmtime GitHub notifications bot (Oct 04 2026 at 21:48):macovedj updated PR #14516.
Wasmtime GitHub notifications bot (Oct 05 2026 at 16:09)::thumbs_up: saulecabrera submitted PR review.
Wasmtime GitHub notifications bot (Oct 05 2026 at 16:09):saulecabrera added PR #14516 winch: restore aarch64 frame pointer before advancing SP to the merge queue.
Wasmtime GitHub notifications bot (Oct 05 2026 at 16:32)::check: saulecabrera merged PR #14516.
Wasmtime GitHub notifications bot (Oct 05 2026 at 16:32):saulecabrera removed PR #14516 winch: restore aarch64 frame pointer before advancing SP from the merge queue.
Last updated: Oct 11 2026 at 04:10 UTC