Question about GCC

[Bo Najdrovsky <bn%okcforum.org@localhost>]

Just a curiosity question... Why is it that GCC will sometimes choke on
me when I try to compile code for the 68040?  The kernel is one of the 
most notable examples of this... when I modified the default -m68020 to
-m68040, the build process chokes about 2/3 ways through the build, 
because the assembler doesn't understand the assembly.  I have gotten
around this by either doing -m68020-40 or by using -m68040 -Wa,-m68030.
I find this second option even more interesting, that telling the assembler
the code is for the 030 it will take the 040 code. Why is this?

Also, I removed -msoft-float from the default compiler flags.  Is there 
a reason why I should leave this option in there since I have a hardware
floating point unit inside the 040?  What I'm trying to do here is 
squeeze out every possible inch of performance from this A3000, so I'm
trying to generate the fastest possible kernel. Can anyone suggest some
other things I could to to make things faster than the default ditribution?

regards,
  Bo Najdrovsky