1265944 - Enable rust for win32 on Firefox 47

Status: RESOLVED WONTFIX

(Firefox Build System :: General, defect)

Description

[Ralph Giles (:rillian)]

Now that the sse2 fix is working on nightly, we'd like to ship rust on Firefox 47 Developer Edition and through to release. This bug is for backporting the relevant changes.

Comment 1

[Ralph Giles (:rillian)]

Attachment: MozReview Request: Bug 1265944 - Update win32 builders for rust 1.9-beta.1. r?rail

Rust 1.8 added unwind support. but 1.9 is the first release
with i586 target support without SSE2 instructions in the
standard library, which we need for compatibility with older
machines, so we need to stay on 1.9 until it's in stable release.

This is a repack of the upstream 1.9.0-beta.1 compiler build
for i686-pc-windows-msvc hosts and both i686 and i586 targets.

This is a backpork of bug 1264490 to Firefox 47.

Review commit: https://reviewboard.mozilla.org/r/47547/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/47547/

Comment 2

[Ralph Giles (:rillian)]

Attachment: MozReview Request: Bug 1265944 - Use rust target i586-pc-windows-msvc on win32. r?rail

This should properly support machines without sse2 instructions.

This is a backport of bug 1261503 to Firefox 47.

Review commit: https://reviewboard.mozilla.org/r/47549/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/47549/

Comment 3

[Ralph Giles (:rillian)]

Attachment: MozReview Request: Bug 1265944 - Re-enable rust on win32 builds. r?rail

Now that we have support for the i586-pc-windows-msvc we
shouldn't have trouble with trying to run sse2 code on
systems without support, and we'd like to get this into
release in Firefox 47.

See bug 1258796 for the corresponding change in Firefox 48.

Review commit: https://reviewboard.mozilla.org/r/47551/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/47551/

Comment 4

[Rail Aliiev [:rail]]

Comment on attachment 8743084 [details]
MozReview Request: Bug 1265944 - Update win32 builders for rust 1.9-beta.1. r?rail

https://reviewboard.mozilla.org/r/47547/#review44435

stamp!

Comment 5

[Rail Aliiev [:rail]]

Comment on attachment 8743085 [details]
MozReview Request: Bug 1265944 - Use rust target i586-pc-windows-msvc on win32. r?rail

https://reviewboard.mozilla.org/r/47549/#review44437

lgtm

Comment 6

[Rail Aliiev [:rail]]

Comment on attachment 8743086 [details]
MozReview Request: Bug 1265944 - Re-enable rust on win32 builds. r?rail

https://reviewboard.mozilla.org/r/47551/#review44439

Comment 7

[Ralph Giles (:rillian)]

Comment on attachment 8743084 [details]
MozReview Request: Bug 1265944 - Update win32 builders for rust 1.9-beta.1. r?rail

Requesting 47 uplift for all patches in this bug. These are backports of bugs 1264490, 1261503, and 1258796 from 48 to match the rust build config for win32 on that branch.

Approval Request Comment
[Feature/regressing bug #]: Bug 1253456

[User impact if declined]: No direct impact on users. We want to get this pilot code into release to advance our rust deployment timeline.

[Describe test coverage new/current, TreeHerder]: Nightly has been building with this configuration for about a week. Builds on try.

[Risks and why]: The major risk is that wider testing will uncover another compatibility issue with the rust code generation like bug 1253202 (addressed by these patches). I don't expect that, but since we also have good testing of this branch with rust disable, any problems can be addressed by turning rust back off. The pilot rust code in firefox has not changed between aurora and nightly, so it should behave equally well here. Therefore I think it is worth the risk of uplift to test our confidence with wider rust code deployment in the Firefox 47 release.

[String/UUID change made/needed]: None

Comment 8

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Comment on attachment 8743084 [details]
MozReview Request: Bug 1265944 - Update win32 builders for rust 1.9-beta.1. r?rail

I've discussed this with JST, Rillian, Anthony, Jimm and it seems risky to let this functionality jump trains even though there are very strong reasons to move to rust compiler long term. We will let this one ride the trains and go live with 48.

Comment 9

[Ralph Giles (:rillian)]

Thanks, Ritu.