1583730 - Use cross-language LTO for standalone SpiderMonkey builds

Status: NEW

(Firefox Build System :: General, enhancement)

Description

[Henri Sivonen (:hsivonen)]

It is my understanding that we currently don't do cross-language LTO for standalone SpiderMonkey builds. We should start doing it in order to make benchmarking in standalone JS shell representative of performance in Firefox.

See https://phabricator.services.mozilla.com/D44470#1421577 for the case motivating this bug.

Comment 1

[Mike Hommey [:glandium]]

That won't help people building their own shell, which is what that person was doing.

Comment 2

[Henri Sivonen (:hsivonen)]

(In reply to Mike Hommey [:glandium] from comment #1)

That won't help people building their own shell, which is what that person was doing.

Considering that we distribute clang via mach bootstrap is it infeasible to provide a config option for a local build with cross-language LTO?

Comment 3

[Mike Hommey [:glandium]]

The option exists: --enable-lto=cross.