Subject: Re: MACHINE_ARCH on mips
To: Eduardo E. Horvath <email@example.com>
From: Todd Vierling <firstname.lastname@example.org>
Date: 07/25/1998 15:21:43
On Sat, 25 Jul 1998, Eduardo E. Horvath wrote:
: AFIK the current model of MACHINE and MACHINE_ARCH doesn't work very well
: where one architecture is a superset of another atchitecture. A mips64
: machine should be able to run mips32 binaries, but not the other way
: around. So what happens? Does MACHINE_ARCH become `mips' and `mips64'
: and the two are wholely incompatible? Does a mips64 machine use a mips32
That depends on what the userland is, as this is where the ambiguity comes
into question. Kernel builds can specify a different compiler/toolchain
option for an output target, but userland has a lot more than just the
NetBSD source tree to deal with.
If, for example, the sparc64 port had a fully 64-bit ELF userland, I'd say
it should have its own MACHINE_ARCH as well. Though it could run sparc
architecture binaries, its native toolchain and binary format would not be
compatible with the baseline MACHINE_ARCH "sparc."
-- Todd Vierling (Personal email@example.com; Bus. firstname.lastname@example.org)