1828648 - JS::WeakCache is not used externally and can be removed from the public headers

Status: RESOLVED FIXED

(Core :: JavaScript: GC, task, P5)

Comment 1

[Jon Coppeard (:jonco)]

Attachment: Bug 1828648 - Part 1: Make SweepingAPI.h an internal header r?jandem

This moves the file from js/public to js/src/gc and moved the template
specialization for GCHashMap into it from js/public/GCHashTable.h.

Comment 2

[Jon Coppeard (:jonco)]

Attachment: Bug 1828648 - Part 2: Move WeakCache into the js namespace r?jandem

Since this is no longer public it can move to the internal namespace.

Depends on D198686

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2592881b3f6d
Part 1: Make SweepingAPI.h an internal header r=jandem
https://hg.mozilla.org/integration/autoland/rev/e6babd625779
Part 2: Move WeakCache into the js namespace r=jandem

Comment 4

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/2592881b3f6d
https://hg.mozilla.org/mozilla-central/rev/e6babd625779

Comment 5

[Philip Chimento [:ptomato]]

I missed this patch going by until now, when I tried building my embedder codebase against ESR128. Unfortunately we relied on JS::WeakCache for a few things, like maintaining a mapping of C++ pointers to JSObjects that could be recreated if needed, but where we'd prefer to return the existing JSObject if one was still live in user code.

Would it be possible to revert this patch and expose JS::WeakCache in the API again? That would certainly be the easiest solution for me.

If that's not possible because further functionality depends on WeakCache being internal, I wonder if it'd be possible to write a replacement using only embedder-available APIs. I've got a draft of something that seems to work, but it only implements the traceWeak part. I'm not sure whether it's possible to implement the sweeping part without using internal APIs.