gcc -mips2 support on indy

[Chris Plummer <darwin.plummer@sun.com>]

I'm just installed Debian 3.0 on my Indy R4600 and am having a problem
with -mips2:

  indy-01$ cc test.c -mips2
  indy-01$ ./a.out
    bash: ./a.out: No such file or directory

  indy-01$ objdump -f a.out
    a.out:     file format elf32-tradbigmips
    architecture: mips:6000, flags 0x00000112:
    EXEC_P, HAS_SYMS, D_PAGED
    start address 0x004004d0

  indy-01$ cc test.c
  indy-01$ ./a.out
    hello

  indy-01$ objdump -f a.out
    a.out:     file format elf32-tradbigmips
    architecture: mips:3000, flags 0x00000112:
    EXEC_P, HAS_SYMS, D_PAGED
    start address 0x004004d0

It appears that the Indy ld refuses to load R6000 (mips II) architecture
modules. However, I don't have this problem with Debian 3.0 on my Cobalt
Qube 2. I can compile and run using -mips2.

The reason I'm using -mips2 is because there is a bug in gcc that causes
it to fail to compile a very large (>32k) function I have. It produces
forward branches to targets that are out of range. Using -mips2 fixes
this problem.

On a related note, how come -mips3 objects can't be linked against the
-mips1 libraries:

  indy-01$ cc test.c -mips3
    /usr/bin/ld: /tmp/ccyFDthq.o: ISA mismatch (-mips3) with previous
modules (-mips1)
    Bad value: failed to merge target specific data of file /tmp/ccyFDthq.o
    collect2: ld returned 1 exit status

I found an SGI Indy FAQ that says for IRIX -mips3 implies n32 calling
conventions. I'm not sure if this is also true with Debian Linux, so I
tried explicitly compiling with -o32, but that didn't help any.

Chris