configuration changes for DYNIX/ptx

[Janis Johnson]

Please consider adding my patch for configuration changes for DYNIX/ptx
(for Sequent computers), submitted on January 16, to gcc 3.0.  The patch
is several hundred lines, but most of that is to remove macro definitions
from config/ptx4.h that are now used from elfos.h and dbxelf.h.  It's been
tested again with bootstraps of snapshot 20010122 on DYNIX/ptx 4.4.7,
4.5.2, and 4.6.0.  I've run the test suite on all of these; there are some
failures, but I don't believe they are due to these changes, since without
these changes it isn't possible to build at all on DYNIX/ptx.

None of the changes in this patch affect operating systems other than
DYNIX/ptx.

> This patch fixes several problems that prevented a bootstrap of 20010115
> on DYNIX/ptx v4.6.  There are remaining problems in the resulting
> compilers, but this fix will let other people get closer to finding and
> fixing those problems, and to building on DYNIX/ptx 4.4 and 4.6.
> 
> The problems fixed here:
> 
>   - Prevents use of bcopy(), which before DYNIX/ptx 4.6 did not handle
>     overlapping memory.
> 
>   - Avoids a bug in the native linker involving alignments for common
>     data.
> 
>   - Passes command line options to native assembler but not to gas.
> 
>   - Removes duplicate macro definitions that were in ptx4.h as well as
>     in elfos.h, and instead includes elfos.h.
> 
> This has been tested with a bootstrap of 20010115 on i386-sequent-sys4
> for DYNIX/ptx 4.6.0, using the native assembler and linker.  Earlier
> versions were tried on DYNIX/ptx 4.4.7 and 4.5.2 using the GNU assembler
> and linker.
> 
> 2001-01-16  Janis Johnson <janis@us.ibm.com>
> 
>         * config.gcc (i[34567]86-sequent-ptx4* | i[34567]86-sequent-sysv4*)):
>         Use new header file if building to use gnu assembler.
>         * config/ptx4.h: Several fixes to build on DYNIX/ptx v4.[456], and
>         to remove macro definitions that are duplicated from elfos.h.
>         * config/i386/ptx4-gas.h: New file.