CDT 10.5.0 / 2021-12 have support for Mac M1 aka Mac on Arm. To make this happen I upgraded the toolset used to build CDT's native components and I have tested it on macOS 10.15*
I don't have access to a Mac M1, so if someone can spin it up and comment on https://bugs.eclipse.org/bugs/show_bug.cgi?id=576533
that it works, that would be great. The parts of CDT that need the native components are items like the TM Terminal and launching programs. However if you see any issues on Mac for Arm please report them.
Gerrit verifications To build the toolset has been updated, as a result the build commands have changed - this means that commits from before  need to be rebased and older releases of CDT won't build now because of this change. If this causes anyone issues, please bring it to my attention and we can consider having multiple tool sets available for the older and newer branches.
CDT 10.5.0 M3 should be out in a few hours.