This bug will track the work needed to use Visual Studio 2017 as the compiler for official Firefox builds on Windows. This is separate from (and dependent on) bug 1318143, which covers support for local VS2017 builds on developer machines.

I've got everything green except for the clang-cl builds, and I worry that it will take me a while to figure out what's broken. Given that the end of nightly 58 is approaching, I don't want to lose too much bake time for our primary builds. I propose to hold clang-cl builds on VS 2015 and deal with them as a followup.

This updates releng.manifest files, and points mozconfig.vs-latest to 2017. sm-tooltool-config.sh may seem strange that I only added the x86 directory. This mirrors the existing behavior: under VS2015's path naming, we only pick up VC/bin and not VC/bin/amd64. I have no idea whether that was intentional. If you think it wasn't, I'm happy to file a followup, but I'm too scared to touch it in this change.

Comment on attachment 8922511 [details] [diff] [review] Temporarily keep clang-cl builds on VS2015 Review of attachment 8922511 [details] [diff] [review]: ----------------------------------------------------------------- Your plan on keeping Clang held back on VS2015 so we don't further delay VS2017 elsewhere seems reasonable to me. Some progress is better than no progress.

Comment on attachment 8922513 [details] [diff] [review] Switch to VS2017 Review of attachment 8922513 [details] [diff] [review]: ----------------------------------------------------------------- \o/ There's definitely some wonkiness with the MSVC paths. I was touching this code several weeks ago and am pretty sure I found some bugs. You are right in being scared into not wanting to touch it in this change. FWIW, most of the mozconfig path adjustment code could be moved to moz.configure. IMO the mozconfigs should just point configure at a standalone MSVC root and be done with it.

Pushed by dmajor@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/76c72fe36a2c Temporarily keep clang-cl builds using VS2015 binaries. r=gps https://hg.mozilla.org/integration/mozilla-inbound/rev/6fe3d70877ed Switch Windows builders to VS2017 15.4.1 with SDK 10.0.16299.0. r=gps

Pushed by dmajor@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/1f2998b72aa7 Touch CLOBBER just in case.

https://hg.mozilla.org/mozilla-central/rev/76c72fe36a2c https://hg.mozilla.org/mozilla-central/rev/6fe3d70877ed https://hg.mozilla.org/mozilla-central/rev/1f2998b72aa7

Pushed by mozilla@jorgk.com: https://hg.mozilla.org/comm-central/rev/103523d052a8 Port Bug 1408789 - Switch Windows builders to VS2017 15.4.1 with SDK 10.0.16299.0. rs=bustage-fix

Backout by mozilla@jorgk.com: https://hg.mozilla.org/comm-central/rev/6c1a4df21134 Backed out changeset 103523d052a8 - Switch Windows builds to VS2017. a=jorgk

This brought some other perf improvements! == Change summary for alert #10246 (as of October 27 2017 15:25 UTC) == Improvements: 5% TestStandardURL NormalizePerfFails windows7-32 opt 18,117.79 -> 17,275.17 3% TestStandardURL NormalizePerfFails windows10-64 opt 12,992.67 -> 12,547.50 For up to date results, see: https://treeherder.mozilla.org/perf.html#/alerts?id=10246