Comment 4 for bug 1904760

I see the same thing for arm-linux-gnueabihf on trunk, also on
insn-extract.o. It's specific to RTL checking for me too.

I found it does work if I bootstrap with --enable-checking=yes,extra,
flip ENABLE_RTL_CHECKING to 1 in auto-host.h, and then recompile
insn-extract.c. But it does take a large amount of VM:

phase parsing : 51.10 ( 27%) 43.64 ( 74%) 94.74 ( 38%) 1334M ( 73%)

This used to work “a while ago” but I don't know when it stopped.

The file has 9975 lines, 435KiB, but that's a bairn compared to some
of the stuff we kick out. Perhaps it's just the sheer number of
(nested) XEXP macro expansions?