DATA_ALIGNMENT vs. DECL_USER_ALIGNMENT

[Ulrich Weigand]

Richard Henderson wrote:

>On Thu, Apr 10, 2003 at 06:35:54PM -0400, Richard Kenner wrote:
>>     I definitely think there's a bug in that the Ada front end sets
>>     DECL_USER_ALIGN for these objects and the C front end (in response to
>>     the auto-generated files) does not.  That mis-match should be
>>     addressed in some way -- either by not setting DECL_USER_ALIGN in Ada
>> 
>> But it *isn't* set in Ada! 
>
>Ulrich's experience clearly belies this.

You probably missed one of the forks of this thread; to clear 
up possible confusion, what happens is that the Ada frontend
does in fact not set DECL_USER_ALIGN, only TYPE_USER_ALIGN.

It is the middle-end (stor-layout.c), that copies TYPE_USER_ALIGN
to DECL_USER_ALIGN.  And in fact, this is done only as a result
of a patch by Jason Merrill as of last week:

http://gcc.gnu.org/ml/gcc-patches/2003-04/msg00209.html

As this patch is a bit complex, I'm not sure if the change in
behaviour (for Ada) was intended or not, but this patch is
definitely the immediate cause of the s390x / Ada problems ...

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  weigand@informatik.uni-erlangen.de