Re: Support bits/syscall.h build for triarch systems

[Roland McGrath <roland at hack dot frob dot com>]

There's nothing really wrong with having such a conditional in case some
sysdeps/.../Makefile turns out to really need it.  But I'm more inclined to
see if we can generalize the common rule so that there's a way to support
all the variants without each port repeating a variant of the same hairy
command sequence.

It seems like it should be doable.  What I have in mind is something like a
standard variable that lists the flavor names (32 and 64 for the common
bi-arch case).  Then variables with names derived from that can contain the
predefines needing -U treatment.  Another variable can list the headers
used to distinguish, or probably better a command sequence to emit the
preamble (what's now "echo '#include <bits/wordsize.h>'; echo '';").  It
will be some fiddly work today to get the rule to work right for the
uniarch, biarch, and triarch examples we have at hand.  But thereafter, any
changes will be in the common place, and new ports won't have to cargo-cult
the big hairy rule across.


Thanks,
Roland