you mean it can not compile on RPI3?You most likely ran out of memory during the world compilation. Syslog should have additional information about this too.
Adding swap would probably not help much here.
I suggest you to crosscompile world/kernel on a stronger HW and copy that to a box.
OK 。I try on my server。I want know how solve the error?12.2-RELEASE has been EOL for almost 2 years. Upgrade to a supported release and try again.
However, most likely you will again run out of memory - those toys aren't really meant for proper workloads. Cross-compile on real hardware like others have already suggested. (or just use the pre-compiled release)