$ta0 .. $ta3 registers in O32 on MIPS

[Ralf Baechle]

The register names $ta0 .. $ta3 were added by SGI for N32 / N64 code.
Because these reference $8 .. $11 just like $t0 .. $t3 in the O32 ABI
their availability in O32 as well appears dangerous, if not a bug:

$ cat s.s 
	addu	$ta0, $ta0
$ mips-linux-as -o s.o s.s
$ file s.o
s.o: ELF 32-bit MSB relocatable, MIPS, MIPS-I version 1 (SYSV), not stripped
$

I was expecting an error message and I'm wondering, was this intentional?

  Ralf