Re: PATCH [mainline] fix -combine bug for parser, gzip of 2000 SPEC benchmark

[Fariborz Jahanian <fjahanian at apple dot com>]

On Sep 29, 2004, at 9:55 AM, Richard Henderson wrote:

> On Wed, Sep 29, 2004 at 08:51:08AM -0700, Fariborz Jahanian wrote:
> > Issued warning tells the whole story.
>
> Perhaps not the whole story.  Why does this only come up for
> multiple translation units?  If I put
>
>   extern int sentence[];
>   int sentence[3];
>   extern int sentence[];
>
> in one translation unit then things work.

Thanks for the clue. Yes, logic for saving DECL_SIZE is already there. 
But it works based on direct type
comparison; something which cannot be relied on when types are coming 
from different TUs. Following
patch offers a simple fix. Bootstrapped, dejagnu tested on 
apple-ppc-darwin.

OK?

- fariborz (fjahanian@apple.com)

ChangeLog:

2004-09-29  Fariborz Jahanian <fjahanian@apple.com>

        * c-decl.c (merge_decls): Use comptype when comparing
        types to decide on DECL_SIZE save of olddecl.


Index: c-decl.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-decl.c,v
retrieving revision 1.590
diff -c -p -r1.590 c-decl.c
*** c-decl.c    28 Sep 2004 19:35:20 -0000      1.590
--- c-decl.c    29 Sep 2004 19:40:46 -0000
*************** merge_decls (tree newdecl, tree olddecl,
*** 1549,1555 ****
      = composite_type (newtype, oldtype);

    /* Lay the type out, unless already done.  */
!   if (oldtype != TREE_TYPE (newdecl))
      {
        if (TREE_TYPE (newdecl) != error_mark_node)
        layout_type (TREE_TYPE (newdecl));
--- 1549,1555 ----
      = composite_type (newtype, oldtype);

    /* Lay the type out, unless already done.  */
!   if (!comptypes (oldtype, TREE_TYPE (newdecl)))
      {
        if (TREE_TYPE (newdecl) != error_mark_node)
        layout_type (TREE_TYPE (newdecl));

> r~