1482516 - Ensure we touch the build backend output list file when re-building the build backend

Status: RESOLVED FIXED

(Firefox Build System :: General, enhancement)

Description

[Chris Manchester (limited bugmail, email directly)]

Bug 1478798 hits an issue with our logic for touching/updating the backend output list: because the current check things the created file count indicates the list has been updated, if we have situation where a backend output file has been removed and re-created but the list hasn't otherwise changed, we'll end up using a FileAvoidWrite and bypassing the additional mtime bump in bug 1216901.

It looks like we should just be comparing the file sets to detect this instead.

Comment 1

[Chris Manchester (limited bugmail, email directly)]

Attachment: Bug 1482516 - Use set comparison to determine whether the list of build backend outputs has changed.

If a backend output file is deleted outside of the build system the non-zero
"created" count can make the current check erroneously think the list of
outputs has changed.

Comment 2

[Gregory Szorc [:gps]]

Comment on attachment 8999287 [details]
Bug 1482516 - Use set comparison to determine whether the list of build backend outputs has changed.

Gregory Szorc [:gps] has approved the revision.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ebe78e2810c5
Use set comparison to determine whether the list of build backend outputs has changed. r=gps,firefox-build-system-reviewers

Comment 4

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/ebe78e2810c5