On Mon, 22 Jan 2001, Rafal Boni wrote:

: -> It seems our gcc defines both "-mcpu=i386" and "-march=pentium" by default.
:
: Given that we expect things to run on any x86 processor down to the '386,
: maybe the defaults should be '-mcpu=pentium -march=i386' by default, in
: other words the opposite of what we do now.

You'd think so, but I've run on a Cyrix 6x86 (486 instruction set) as well
as a 486DX-33 with the precompiled system binaries, so one of the following
must be true:

 1. -mcpu=i386 pulls down -march= to i386 at codegen time;
 2. gcc 2.91 (egcs 1.1) doesn't have many (or any) instruction definitions
    for post-i386 machines;
 3. the doc is wrong;
 4. gcc does something Very Strange that makes the binaries just happen to
    work.

I personally suspect one of (1) or (2).  I recall reading something about
gcc not knowing newer instructions than i386, some time ago.

-- 
-- Todd Vierling <tv@wasabisystems.com>  *  Wasabi NetBSD:  Run with it.
-- NetBSD 1.5 now available on CD-ROM  --  http://www.wasabisystems.com/