On Wed, Dec 13, 2023 at 08:48:49PM -0500, Jason Merrill wrote:
> On 11/27/23 10:58, Patrick Palka wrote:
> > gcc/cp/ChangeLog:
> >
> > * cp-tree.h (type_targs_deducible_from): Adjust return type.
> > * pt.cc (alias_ctad_tweaks): Handle C++23 inherited CTAD.
> > (inherited_ctad_tweaks): Define.
> > (type_targs_deducible_from): Return the deduced arguments or
> > NULL_TREE instead of a bool. Handle 'tmpl' being a TREE_LIST
> > representing a synthetic alias template.
> > (ctor_deduction_guides_for): Do inherited_ctad_tweaks for each
> > USING_DECL in C++23 mode.
> > (deduction_guides_for): Add FIXME for stale cache entries in
> > light of inherited CTAD.
>
> check_GNU_style.py notices a few too-long lines in comments:
>
> > === ERROR type #2: lines should not exceed 80 characters (3 error(s)) ===
> > gcc/cp/pt.cc:30076:80: /* FIXME this should mean they
> > don't compare as equivalent. */
> > gcc/cp/pt.cc:30138:80: class template TMPL; adjust the base's guides be
> > deduction guides for TMPL. */
> > gcc/cp/pt.cc:30190:80: /* If tmpl is a class template, this is
> > trivial: it's deducible if TYPE is a
>
> OK with those fixed.
> > index 4624794c4b7..74f92325d7a 100644
> > --- a/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
> > +++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
> > @@ -1,5 +1,4 @@
> > -// Deduction from inherited constructors isn't supported yet, but we
> > shouldn't
> > -// crash. It may well be supported in C++23.
> > +// Deduction from inherited constructors isn't supported before C++23.
> > //{ dg-do compile { target c++17 } }
> > @@ -17,5 +16,5 @@ int main()
> > {
> > B b = 42; // { dg-line init }
> > // { dg-prune-output "no matching function" }
> > - // { dg-error "class template argument deduction" "" { target *-*-* }
> > init }
> > + // { dg-error "class template argument deduction" "" { target c++23_down
> > } init }
> > }
I checked in this patch:
-- >8 --
The test says that CTAD from inherited constructors doesn't work
before C++23 so we should use c++20_down for the error.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1z/class-deduction67.C: Correct dg-error target.
---
gcc/testsuite/g++.dg/cpp1z/class-deduction67.C | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
b/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
index 74f92325d7a..fa1523d99d5 100644
--- a/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction67.C
@@ -16,5 +16,5 @@ int main()
{
B b = 42; // { dg-line init }
// { dg-prune-output "no matching function" }
- // { dg-error "class template argument deduction" "" { target c++23_down }
init }
+ // { dg-error "class template argument deduction" "" { target c++20_down }
init }
}
base-commit: e5e1999aa664333f766f3e6cc6996f769d50ae7a
--
2.43.0
