Delete the Atomics.waitAsync() polyfill#25494
Merged
juj merged 2 commits intoemscripten-core:mainfrom Oct 6, 2025
Merged
Conversation
…polyfill over the usage pattern in Emscripten mailbox implementation. See emscripten-core#25449 (comment) . The mailbox implementation has its own postMessage() fallback, so does not need the polyfill. Fixes test browser.test_gl_textures_pthreads_main_module in Firefox."
5eb6c1a to
29a1295
Compare
tlively
approved these changes
Oct 6, 2025
Member
tlively
left a comment
There was a problem hiding this comment.
Oh yeah, wow, that's totally broken.
juj
added a commit
to juj/emscripten
that referenced
this pull request
Oct 6, 2025
This reverts commit d9e0690.
juj
added a commit
that referenced
this pull request
Oct 6, 2025
This reverts commit d9e0690. Oops, it looks like we do have several tests that depended on the polyfill: http://clbri.com:8010/api/v2/logs/89393/raw_inline In particular: ``` browser.test_wasm_worker_cancel_all_wait_asyncs browser.test_wasm_worker_cancel_all_wait_asyncs_at_address browser.test_wasm_worker_cancel_all_wait_asyncs_at_address_minimal_runtime browser.test_wasm_worker_cancel_all_wait_asyncs_minimal_runtime browser.test_wasm_worker_cancel_wait_async browser.test_wasm_worker_cancel_wait_async_minimal_runtime browser.test_wasm_worker_wait_async browser.test_wasm_worker_wait_async_minimal_runtime ``` CircleCI just didn't have coverage of these functions on Firefox. Revert this PR until we can reinstate it in a form that applies the polyfill to only these functions.
juj
added a commit
to juj/emscripten
that referenced
this pull request
Nov 22, 2025
…ipten_thread_mailbox_await(), since the polyfill will not work there. This is take two at fixing emscripten-core#25494.
inolen
pushed a commit
to inolen/emscripten
that referenced
this pull request
Feb 13, 2026
Delete the Atomics.waitAsync() polyfill, which is not good enough to polyfill over the usage pattern in Emscripten mailbox implementation. See emscripten-core#25449 (comment) . The mailbox implementation has its own postMessage() fallback, so does not need the polyfill. Fixes test browser.test_gl_textures_pthreads_main_module in Firefox." This will be a breaking change to any users who successfully depended on the polyfill (i.e. only needed the partial support it brought), though it is uncertain if there are any. Fixes test `browser.test_gl_textures_pthreads_main_module` on Firefox.
inolen
pushed a commit
to inolen/emscripten
that referenced
this pull request
Feb 13, 2026
…" (emscripten-core#25501) This reverts commit d9e0690. Oops, it looks like we do have several tests that depended on the polyfill: http://clbri.com:8010/api/v2/logs/89393/raw_inline In particular: ``` browser.test_wasm_worker_cancel_all_wait_asyncs browser.test_wasm_worker_cancel_all_wait_asyncs_at_address browser.test_wasm_worker_cancel_all_wait_asyncs_at_address_minimal_runtime browser.test_wasm_worker_cancel_all_wait_asyncs_minimal_runtime browser.test_wasm_worker_cancel_wait_async browser.test_wasm_worker_cancel_wait_async_minimal_runtime browser.test_wasm_worker_wait_async browser.test_wasm_worker_wait_async_minimal_runtime ``` CircleCI just didn't have coverage of these functions on Firefox. Revert this PR until we can reinstate it in a form that applies the polyfill to only these functions.
inolen
pushed a commit
to inolen/emscripten
that referenced
this pull request
Feb 13, 2026
…ipten_thread_mailbox_await() (emscripten-core#25853) When Atomics.wait() is polyfilled, do not attempt to use it in _emscripten_thread_mailbox_await(), since the polyfill will not work there. This is take two at fixing emscripten-core#25494.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Delete the Atomics.waitAsync() polyfill, which is not good enough to polyfill over the usage pattern in Emscripten mailbox implementation. See #25449 (comment) . The mailbox implementation has its own postMessage() fallback, so does not need the polyfill. Fixes test browser.test_gl_textures_pthreads_main_module in Firefox."
This will be a breaking change to any users who successfully depended on the polyfill (i.e. only needed the partial support it brought), though it is uncertain if there are any.
Fixes test
browser.test_gl_textures_pthreads_main_moduleon Firefox.