These seem to be the two relevant commits
Differential Revision: https://phabricator.services.mozilla.com/D98421
gitlab.com
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...
gitlab.com
The change that motivated bumping to 10.12 was that `clock_gettime` and such are not available on < 10.12. This is easily polyfilled though, see macports legacysupport.
Once that is done, building with the older SDK should work.
Interestingly they still seem to target 10.9 as min though,
https://gitlab.com/seamonkey-projec...mmit/1262c05bfa42fb479cdc61c14da8c3406397d77a so I don't quite understand what's happening.. I wouldn't be surprised if Apple just never bothers testing newer sdks with old target mins though.
In fact, compared to chromium or newer firefox, the fact that seamonkey uses the old XUL and is unlikely to ever have any major GUI changes is a point of stability, since it means that it will likely not ever try to make use of new cocoa APIs. (The fact that all this time it has been built with 10.11 SDK and yet works perfectly fine with 10.9 is a testament to that)
Someone with spare CPU cycles please try the build? (Compared to building chromium this seems a lot more straightforward). Would be good if we could get an alternative to chromium-legacy.
CC:
@Wowfunhappy maybe a project if you're bored and have cpu cycles to waste...
