fix: guard asyncify_stop_unwind() for async web API import unwinds (issue #7)#26
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JosefVacha wants to merge 1 commit into
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fix: guard asyncify_stop_unwind() for async web API import unwinds (issue #7)#26JosefVacha wants to merge 1 commit into
JosefVacha wants to merge 1 commit into
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…ssue #7) Only call asyncify_stop_unwind() when pl_asyncify_unwind_buf is non-NULL, which indicates a C-level (setjmp/longjmp/scan) unwind. When an asyncify import like call_host_function triggers an unwind, the transform bypasses our macro so pl_asyncify_unwind_buf stays NULL. Calling asyncify_stop_unwind() in that case clears __asyncify_state from 1 (UNWINDING) to 0 before the export returns to JS, hiding the pending async op from asyncify-wasm. Fixes #7 Based on PR #25 by @itsbryanman
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Problem (Root Cause)
The runtime loop in stubs/runtime.c unconditionally called asyncify_stop_unwind() after every return from main(). When an asyncify import (call_host_function) triggered an unwind, this call cleared __asyncify_state from 1 (UNWINDING) to 0 before the export returned to JavaScript. The asyncify-wasm host then saw state 0, assumed normal termination, and never awaited the pending Promise -> the async call was silently dropped.
Solution (The Fix)
Introduced a guard using the existing variable pl_asyncify_unwind_buf:
Changes
Fixes
Closes #7
Based on PR #25 by @itsbryanman