Add checks for PROXY_SYNC_ASYNC#26209
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stephenduong1004 wants to merge 1 commit intoemscripten-core:mainfrom
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Add checks for PROXY_SYNC_ASYNC#26209stephenduong1004 wants to merge 1 commit intoemscripten-core:mainfrom
stephenduong1004 wants to merge 1 commit intoemscripten-core:mainfrom
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Check if the returned value is actually a Promise before attempting to use it as one. I got en error when using `fd_sync` without ASYNCIFY: https://github.com/emscripten-core/emscripten/blob/main/src/lib/libwasi.js#L556. It is assigned `__proxy: 'sync'` (https://github.com/emscripten-core/emscripten/blob/main/src/lib/libcore.js#L2627), making it being proxied using PROXY_SYNC_ASYNC mode while not being a Promise.
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I think maybe we should instead mark the function as Also, we should add a test for this. Can you explain how you were able to reproduce? |
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This function is marked as `__async: 'auto'` which means it should return a promise when run in proxied mode on the main thread. However it wasn't always returning a promise. Adding the `async` keyword is the simplest way to ensure it always returns a promise. Also, update the `wrapSyscallFunction` function to preserve the async keyword. Replaces: emscripten-core#26209
sbc100
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This function is marked as `__async: 'auto'` which means it should return a promise when run in proxied mode on the main thread. However it wasn't always returning a promise. Adding the `async` keyword is the simplest way to ensure it always returns a promise. Also, update the `wrapSyscallFunction` function to preserve the async keyword. Replaces: emscripten-core#26209
sbc100
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to sbc100/emscripten
that referenced
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Feb 3, 2026
This function is marked as `__async: 'auto'` which means it should return a promise when run in proxied mode on the main thread. However it wasn't always returning a promise. Adding the `async` keyword is the simplest way to ensure it always returns a promise. Also, update the `wrapSyscallFunction` function to preserve the async keyword. Replaces: emscripten-core#26209
sbc100
added a commit
to sbc100/emscripten
that referenced
this pull request
Feb 5, 2026
This function is marked as `__async: 'auto'` which means it should return a promise when run in proxied mode on the main thread. However it wasn't always returning a promise. Adding the `async` keyword is the simplest way to ensure it always returns a promise. Also, update the `wrapSyscallFunction` function to preserve the async keyword. Replaces: emscripten-core#26209
sbc100
added a commit
that referenced
this pull request
Feb 5, 2026
This function is marked as `__async: 'auto'` which means it should return a promise when run in proxied mode. Also, update the `wrapSyscallFunction` function to preserve the async keyword. This fix was needed when investigating using the `async` keyword instead. Even though it didn't end up working in this case its still a worthwhile fix. Replaces: #26209 --------- Co-authored-by: Alon Zakai <alonzakai@gmail.com>
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Check if the returned value is actually a Promise before attempting to use it as one.
I got en error when using
fd_syncwithout ASYNCIFY: https://github.com/emscripten-core/emscripten/blob/main/src/lib/libwasi.js#L556. It is assigned__proxy: 'sync'(https://github.com/emscripten-core/emscripten/blob/main/src/lib/libcore.js#L2627), making it being proxied using PROXY_SYNC_ASYNC mode while not being a Promise.