It appears that debugging armv7 binaries on arm64 is broken.
I've created an armv7 jail on an arm64 FreeBSD 13.0-RELEASE system, entered it, and install gdb from ports. Then I executed an arbitrary program under gdb, set a breakpoint and let the program run (a simple way to do this is to type "start"). The breakpoint is reached and gdb informs me that a SIGBUS was delivered to the program; attempting to continue after this breakpoint is impossible.
I suppose there's something wrong here as debugging on a native armv7 system seems to work fine.
Any idea if this is a regression with respect to older FreeBSD versions?
(In reply to Mark Johnston from comment #1)
Older FreeBSD versions do not support execution of armv7 binaries on arm64.
So I suppose it is not.