[RFC/RFA] fix cygwin GDB "long long" return value error

[Pierre Muller <muller@cerbere.u-strasbg.fr>]

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  This RFC/RFA is the followup of the thread about
that I started with the folliwng subject:

  [RFC] cygwin GDB "long long" return value error

At 21:07 04/10/01 , Mark Kettenis a écrit:
>Pierre Muller <pierre@idefix.wisa.be> writes:
>
> >   This macro has a correct implementation in config/i386/tm-i386.h
> > where 64bit integers are taken from the edx:eax pair.
>
>Nowadays it's a function in i386-tdep.c.
>
> >   But config/i386/tm-i386v.h overwrites this macro
> > by using memcpy on the register buffer, which then leads to
> > using ecx:eax as return value.
>
>Yep.  I don't know what the origional System V compiler did, but it's
>unlikely that it did return 64-bit quantities in ecx:eax, if it
>supported 64-bit quantities at all.  I have a patch that removes most
>of the presumably unecessary junk from tm-i386v.h.  I might as well
>post it.
>
> >   As cygwin version relies on tm-i386v.h,
> > the 64bit integers are wrong.
>
>IMHO cygwin shouldn't include tm-i386v.h.  tm-i386.h already the
>necessary stuff, and really does a better job at it.  Cygwin
>defenitely isn't derived from System V.

Yes, but I tried to change tm-i386v.h into tm-i386.h
it comiples OK and fixes trhe long klong errors that I reported first;
but I have no idea if it does make other good or bad changes.
It is probably necessary to run the testsuite before and after applying 
this patch, but
I can't do that on my machine.

ChangeLog:

2001-10-05 Pierre Muller <muller@ics.u-strasbg.fr>

         * config/i386/tm-cygwin.h: include tm-i386.h instead of tm-i386v.h.
              This fixes errors in "long long" handling for 'finish' and 
'return' commands.

Index: config/i386/tm-cygwin.h
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/tm-cygwin.h,v
retrieving revision 1.8
diff -r1.8 tm-cygwin.h
26c26
< #include "i386/tm-i386v.h"
---
 > #include "i386/tm-i386.h"

> >   Anyhow STORE_RETURN_VALUE in config/i386/tm-i386.h
> > suffers from the same error, the "long long" value will be copied
> > into ecx:eax instead of edx:eax
>
>Fixed in the current sources (both mainline and the 5.1 branch) :-).

   Yes, I saw it now and it does indeed work OK for go32v2 target.
(My latest go32v2 build was older ..)

Could someone, (Christopher ?) explains us why
tm-cygwin.h includes tm-i386v.h when as Mark Kettenis said,
Cygwin is not derived from System V ?



Pierre Muller
Institut Charles Sadron
6,rue Boussingault
F 67083 STRASBOURG CEDEX (France)
mailto:muller@ics.u-strasbg.fr
Phone : (33)-3-88-41-40-07  Fax : (33)-3-88-41-40-99