Stream: git-wasmtime

Topic: wasmtime / PR #12052 Debugging: force hostcall-based-trap...

Wasmtime GitHub notifications bot (Nov 20 2025 at 01:43):

cfallin opened PR #12052 from cfallin:debuggees-may-not-use-signals-sorry-only-hostcalls-for-you to bytecodealliance:main:

We manually configure this for tests now but this change formalizes the dependence on hostcall-based traps that we outlined in #11964.

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Wasmtime GitHub notifications bot (Nov 20 2025 at 01:43):

cfallin requested pchickey for a review on PR #12052.

Wasmtime GitHub notifications bot (Nov 20 2025 at 01:43):

cfallin requested wasmtime-core-reviewers for a review on PR #12052.

Wasmtime GitHub notifications bot (Nov 20 2025 at 01:57):

cfallin updated PR #12052.

Wasmtime GitHub notifications bot (Nov 20 2025 at 02:09):

alexcrichton submitted PR review:

Looks reasonable to me, but one thing I think would be worthwhile to catch is to return an error on .guest_debug(true).signals_based_traps(true). Auto-turning-off makes sense to me, but it can be confusing when an automatic setting conflicts with something that was explicitly configured because it can lead to questions of "why is my explicit setting not being respected".

To implement this I'd recommend moving this if block to above self.tunables.configure where tunables.signals_based_traps is disabled if self.tunables.debug_guest is Some(true). Then afterwards where we already ensure feature = "debug" is enabled there'd be a second configuration validation that if tunables.debug_guest is enabled the tunables.signals_based_traps must also be disabled. That should then only be possible to trip by explicitly configuring the option I believe.

Also, after doing this, mind adding a test that engine creation fails of signals-based-traps is enabled with guest-debug?

Wasmtime GitHub notifications bot (Nov 20 2025 at 02:24):

cfallin updated PR #12052.

Wasmtime GitHub notifications bot (Nov 20 2025 at 02:24):

cfallin commented on PR #12052:

Ah, yep, good call -- thanks! Added new logic and test in f9b643f374.

Wasmtime GitHub notifications bot (Nov 20 2025 at 02:25):

cfallin has enabled auto merge for PR #12052.

Wasmtime GitHub notifications bot (Nov 20 2025 at 04:46):

github-actions[bot] commented on PR #12052:

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Wasmtime GitHub notifications bot (Nov 20 2025 at 19:09):

cfallin commented on PR #12052:

Merge queue failure was from lack of a uadd_overflow lowering on s390x -- fixed in #12057; will rebase this and reland once that goes in.

Wasmtime GitHub notifications bot (Nov 20 2025 at 23:46):

cfallin merged PR #12052.

Last updated: Jan 10 2026 at 02:36 UTC