Avoid 64-bit Solaris/SPARC -gstabs link failures (PR ld/12152)

[David Miller]

From: Eric Botcazou <ebotcazou@adacore.com>
Date: Fri, 2 Mar 2012 19:22:50 +0100

>> I'd like to know why it's OK to just let the relocation overflow in
>> these cases, doesn't it make the debugging information unusable and
>> incorrect?
> 
> Yes, STABS aren't (generally) usable with 64-bit architectures.

Then this would suggest GCC shouldn't emit them in the first place.

Isn't Solaris using dwarf2 by now?  What blocks us from emitting
dwarf2 by default at least for 64-bit sparc under Solaris?