I'm unable to build Firefox locally on OSX. It looks like the code in question was added by bug 1678174.

Reverting the patch seems to fix it ( https://hg.mozilla.org/integration/autoland/rev/491fa5186e7f )

POSIX is pretty unambiguous here:

All implementations shall support a clock_id of CLOCK_REALTIME as defined in <time.h>.

But Apple's headers are weird (abridged for clarity):

#define __CLOCK_AVAILABILITY __OSX_AVAILABLE(10.12) …
…
typedef enum {
_CLOCK_REALTIME __CLOCK_AVAILABILITY = 0,
#define CLOCK_REALTIME _CLOCK_REALTIME
…

Maybe it doesn't include POSIX clock support if it thinks the target OS might be older than 10.12?

From some discussion on Element in developers with Glandium, it appears the problem is that I'm using the 10.11 SDK.

Bug 1680152 updated automation to use the 10.12 SDK, and shortly after,
bug 1678174 introduced a change that broke the build with the 10.11 SDK.
Considering we haven't actually supported running on macos 10.11 and
earlier since Firefox 79, and that still supporting building with the
10.11 SDK would mean adding and maintaining code that, in practice,
would never be used by users, I think it is fair at this point that we
just drop support for the 10.11 SDK entirely.

Could you send an announcement to mozilla.dev.platform about this? We've generally recommended everyone build with the 10.11 SDK, so lots of people will need to change their setup.

Furthermore, the following pieces of documentation need to be updated:

• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/docs/setup/macos_build.rst#153
• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/widget/cocoa/docs/macos-apis.md#66-69
• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/widget/cocoa/docs/sdks.md#22-29

A few more: https://searchfox.org/mozilla-central/search?q=macosx10.11&path=docs

(In reply to Markus Stange [:mstange] from comment #5)

Could you send an announcement to mozilla.dev.platform about this? We've generally recommended everyone build with the 10.11 SDK, so lots of people will need to change their setup.

Done already.

(In reply to Markus Stange [:mstange] from comment #6)

Furthermore, the following pieces of documentation need to be updated:

• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/docs/setup/macos_build.rst#153
• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/widget/cocoa/docs/macos-apis.md#66-69
• https://searchfox.org/mozilla-central/rev/71621bfa47a371f2b1ccfd33c704913124afb933/widget/cocoa/docs/sdks.md#22-29

Can you paste that in bug 1680441?

Thanks! Done.

Set release status flags based on info from the regressing bug 1678174

https://hg.mozilla.org/mozilla-central/rev/3c639828681a