On Wed, 19 Jun 2024, Jakub Jelinek wrote:
> On Wed, Jun 19, 2024 at 08:04:55AM +0200, Richard Biener wrote:
> > >> Note a canonical type should always be unqualified (for
> > >> classical qualifiers, not address space or atomic qualification)
> > >
> > > The logic in build_qualified_type is the same as in this patch,
> > > it constructs TYPE_CANONICAL with qualifiers. Or what am I
> > > missing?
> >
> > Nothing if you chose to do TYPE_QUALS (canonical) by copy-pasting.
>
> As I mentioned earlier, I'd prefer the following version and I have
> already tested it on the testcases (note, some changes to the tests,
> e.g. using lto effective target), just haven't bootstrapped/regtested it
> fully yet.
LGTM, but I'd defer to a FE maintainer for approval.
Richard.
> gcc/c/
> * c-decl.cc (c_update_type_canonical): Assert t is main variant
> with 0 TYPE_QUALS. Simplify and don't use check_qualified_type.
> gcc/testsuite/
> * gcc.dg/pr114930.c: New test.
> * gcc.dg/pr115502.c: New test.
>
> --- gcc/c/c-decl.cc.jj 2024-06-07 12:17:09.582969919 +0200
> +++ gcc/c/c-decl.cc 2024-06-18 21:30:22.881904947 +0200
> @@ -9367,18 +9367,16 @@ is_flexible_array_member_p (bool is_last
> static void
> c_update_type_canonical (tree t)
> {
> - for (tree x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
> + gcc_checking_assert (TYPE_MAIN_VARIANT (t) == t && !TYPE_QUALS (t));
> + for (tree x = t; x; x = TYPE_NEXT_VARIANT (x))
> {
> if (x != t && TYPE_STRUCTURAL_EQUALITY_P (x))
> {
> - if (TYPE_QUALS (x) == TYPE_QUALS (t))
> + if (!TYPE_QUALS (x))
> TYPE_CANONICAL (x) = TYPE_CANONICAL (t);
> - else if (TYPE_CANONICAL (t) != t
> - || check_qualified_type (x, t, TYPE_QUALS (x)))
> + else
> TYPE_CANONICAL (x)
> = build_qualified_type (TYPE_CANONICAL (t), TYPE_QUALS (x));
> - else
> - TYPE_CANONICAL (x) = x;
> }
> else if (x != t)
> continue;
> --- gcc/testsuite/gcc.dg/pr114930.c.jj 2024-06-18 21:27:53.782729543
> +0200
> +++ gcc/testsuite/gcc.dg/pr114930.c 2024-06-18 21:27:53.782729543 +0200
> @@ -0,0 +1,9 @@
> +/* PR c/114930 */
> +/* { dg-do compile { target lto } } */
> +/* { dg-options "-std=c23 -flto" } */
> +
> +typedef struct WebPPicture WebPPicture;
> +typedef int (*WebPProgressHook)(const WebPPicture *);
> +WebPProgressHook progress_hook;
> +struct WebPPicture {
> +} WebPGetColorPalette(const struct WebPPicture *);
> --- gcc/testsuite/gcc.dg/pr115502.c.jj 2024-06-18 21:27:53.793729408
> +0200
> +++ gcc/testsuite/gcc.dg/pr115502.c 2024-06-18 21:27:53.793729408 +0200
> @@ -0,0 +1,9 @@
> +/* PR c/115502 */
> +/* { dg-do compile { target lto } } */
> +/* { dg-options "-std=c23 -flto" } */
> +
> +typedef struct _OSet OSet;
> +typedef OSet AvlTree;
> +void vgPlain_OSetGen_Lookup(const OSet *);
> +struct _OSet {};
> +void vgPlain_OSetGen_Lookup(const AvlTree *);
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
