Add __async: auto decorator
#26019
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Add __async: auto decorator
#26019
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brendandahl
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Dec 30, 2025
src/jsifier.mjs
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| } | ||
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|
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| const isAsyncFunction = LibraryManager.library[symbol + '__async']; | ||
| if (ASYNCIFY && isAsyncFunction == 'auto') { |
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For JSPI, I don't think we even need the handleAsync. Though there still may be some issues with balanced runtimeKeepalivePush runtimeKeepalivePop. Maybe worth a try?
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Yes, I think handleAsync is used to keep the runtime alive using runtimeKeepalivePush which I think this currently important. We can look at further simplification are followups perhaps, but for now I'd rather leave the semantics as matching.
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brendandahl
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Jan 5, 2026
This decorator automatically generates the Asyncify.handleAsync wrapper code. Hopefully we can transition all out `__async` functions soon and just make this the default.
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Jan 14, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
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Jan 15, 2026
Followup to #26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
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Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
Followup to emscripten-core#26019. I'm not sure about the meaning of the comment here, but `__async: auto` uses `handleAsync` under the hood and it seems to work just fine.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 15, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Jan 16, 2026
The only function that remains that still uses `async: true` is `emscripten_fiber_swap`, and this is because it doesn't use handleSleep or handleAsync, so is not a candidate for `async: auto`. Followup to emscripten-core#26019 and emscripten-core#26095.
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This decorator automatically generates the Asyncify.handleAsync wrapper code. Hopefully we can transition all out
__asyncfunctions soon and just make this the default.