Remove obsolete Tru64 UNIX V5.1B support

[Richard Henderson]

On 03/05/2012 09:14 AM, Rainer Orth wrote:
> * In the alpha backend, there are a couple of cases that might be
>   osf-specific, but I cannot tell for certain:
> 
>   macro				  osf5.h        alpha.h
> 
>   TARGET_AS_CAN_SUBTRACT_LABELS	  1		TARGET_GAS
> 
>   I cannot tell if !TARGET_GAS configurations exist, especially Alpha VMS.
>   Also, in alpha.h there are some references to mips-tfile, which is
>   gone with osf.  If there are no non-gas configrations remaining, that
>   stuff can go, too.

Given that GAS supports VMS, I suspect that all targets are now GAS.
I'll let the adacore folks answer that for certain howeverl.

>   TARGET_HAS_XFLOATING_LIBS	  1		TARGET_LONG_DOUBLE_128
> 
>   Same here: any configurations with !TARGET_LONG_DOUBLE_128?

I wouldn't think so; glibc before version 2.4, circa 1998?

>   HAVE_STAMP_H                    1
> 
>   In my understanding, this is purely a OSF thing and can go, but maybe
>   other OSes on alpha mimiced OSF here?

I've no idea what that actually is.

I'll have a look at the patch in detail later....

r~