Re: mipsisa32-unknown-elf-as: Error: too large constant specified

[Ian Lance Taylor <ian at wasabisystems dot com>]

Ian Lance Taylor <ian@wasabisystems.com> writes:

> Nigel Stephens <nigel@mips.com> writes:
> 
> > I believe that this new behaviour is broken.
> 
> cgd@broadcom.com writes:
> 
> > I'd guess this is a recent regression.
> 
> Hey, I'm easy.  Any opinions on this patch?  I haven't tried the
> testsuite yet.  In any case, clearly some new tests are called for
> here.

Just to spell it out, that patch is a hack on the current behaviour.
It would be more correct, or perhaps I should say less likely to lead
to surprises, to actually compute using 32 bit arithmetic.  But that
would require some real work on expr.c, which right happily does stuff
like:

	    else if (c == '~' || c == '"')
	      expressionP->X_add_number = ~ expressionP->X_add_number;

X_add_number has type offsetT aka bfd_signed_vma.  When targeting
MIPS, that will often be a 64-bit type, because many MIPS targets
include a 64-bit BFD target vector.

With the patch I sent out, code like this will assemble without a
warning on a 32-bit target:
	and	$2, $2, 0xffffffffe0000000
which is somewhat dubious.

Ian