Subject: re: IMPORTANT: MACHINE_ARCH WRONG ON MIPS PLATFORMS
To: Jonathan Stone <jonathan@DSG.Stanford.EDU>
From: Todd Vierling <tv@pobox.com>
List: tech-toolchain
Date: 07/23/1998 14:44:26
On Thu, 23 Jul 1998, Jonathan Stone wrote:
: The right fix is that we build bi-endian toolchains for mips, so that
: we can compile for mipsel on a mipseb with the "native" toolchain, and
: vice-versa. so we'd always configure
That "fixes" the bfd stuff. But I never said anything against it; some
platforms (m68k, sparc, i386) now build an ELF-capable toolchain.
: The reason we don't is that FSF/Cygnus codebase still thinks that
: mipsel == mips-dec-* (pmaxes are the only little-endian mips), and all
: other mips are big-endian. Once we fix that, most of the problems
: you're asking about go away.
Not quite. You forgot to address how binary pkgs are known to be useable
across a given ${MACHINE_ARCH} - or how ${MACHINE_ARCH} could be used to
uniquely identify a given binary. ``Historical precedent'' or not, it's
_actively_ used for that.
: >Regardless of the chip involved, a little endian system and a big endian
: >system are _not_ the same architecture.
:
: Huh? CPUs of the same chip type or family *are* of the same
: architecture. That's what computer ``architecture'' means!
An architecture is described by both its hardware and its software. In most
cases, programs that care about the difference are caring about the
_software_ architecture.
MACHINE_ARCH is currently used to define a software and hardware
architecture. That means the current definition of "mips" is broken.
--
-- Todd Vierling (Personal tv@pobox.com; Bus. todd_vierling@xn.xerox.com)