gdb from the devel/gdb port can now properly examine cores from a 32-bit
(i386) process on amd64. It can also attach to running 32-bit processes
and start a new process for a 32-bit binary. Previously it emitted
warnings about ld-elf.so.1 for the first two cases (though it did work
aside from rtld symbols being wrong) and the third case resulted in a
segfault during early startup.
The in-tree gdb isn't able to grok 32-bit core dumps on amd64, but
otherwise appears to be similar.