diff options
| author | Patrick Palka <ppalka@redhat.com> | 2025-04-05 22:39:15 -0400 |
|---|---|---|
| committer | Patrick Palka <ppalka@redhat.com> | 2025-04-05 22:39:15 -0400 |
| commit | 7a91400c142899ea0aeb8b62577496cf24c68156 (patch) | |
| tree | 4b050c8ae9fca711abfd314eb31229ef097f4822 | |
| parent | 58c5055162b698dab6a493b1f90c18af1a34ac65 (diff) | |
| download | gcc-7a91400c142899ea0aeb8b62577496cf24c68156.zip gcc-7a91400c142899ea0aeb8b62577496cf24c68156.tar.gz gcc-7a91400c142899ea0aeb8b62577496cf24c68156.tar.bz2 | |
c++: maybe_dependent_member_ref and typenames [PR118626]
Here during maybe_dependent_member_ref for accepted_type<_Up>, we
correctly don't strip the typedef because it's a complex one (its
defaulted template parameter isn't used in its definition) and so
we recurse to consider its corresponding TYPE_DECL.
We then incorrectly decide to not rewrite this use because of the
TYPENAME_TYPE shortcut. But I don't think this shortcut should apply to
a typedef TYPE_DECL.
PR c++/118626
gcc/cp/ChangeLog:
* pt.cc (maybe_dependent_member_ref): Restrict TYPENAME_TYPE
shortcut to non-typedef TYPE_DECL.
gcc/testsuite/ChangeLog:
* g++.dg/cpp2a/class-deduction-alias25a.C: New test.
Reviewed-by: Jason Merrill <jason@redhat.com>
| -rw-r--r-- | gcc/cp/pt.cc | 3 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp2a/class-deduction-alias25a.C | 19 |
2 files changed, 21 insertions, 1 deletions
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index 23e41a0..95b89f12 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -17789,7 +17789,8 @@ maybe_dependent_member_ref (tree t, tree args, tsubst_flags_t complain, if (TREE_CODE (t) == TYPE_DECL) { - if (TREE_CODE (TREE_TYPE (t)) == TYPENAME_TYPE + if (!is_typedef_decl (t) + && TREE_CODE (TREE_TYPE (t)) == TYPENAME_TYPE && TYPE_NAME (TREE_TYPE (t)) == t) /* The TYPE_DECL for a typename has DECL_CONTEXT of the typename scope, but it doesn't need to be rewritten again. */ diff --git a/gcc/testsuite/g++.dg/cpp2a/class-deduction-alias25a.C b/gcc/testsuite/g++.dg/cpp2a/class-deduction-alias25a.C new file mode 100644 index 0000000..74ef1e4 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/class-deduction-alias25a.C @@ -0,0 +1,19 @@ +// PR c++/118626 +// { dg-do compile { target c++20 } } + +template<long> struct _Nth_type { using type = _Nth_type; }; + +template<class _Up> +struct variant { + template<class _Tp> static constexpr long __accepted_index = 0; + template<long _Np> using __to_type = typename _Nth_type<_Np>::type; + template<class _Tp, int = sizeof(_Tp)> using __accepted_type = __to_type<__accepted_index<_Tp>>; + template<class = __accepted_type<_Up>> variant(_Up); +}; + +template<class _Tp> +struct Node { Node(_Tp); }; + +template<class R> using Tree = variant<Node<R>>; +using type = decltype(Tree{Node{42}}); +using type = Tree<int>; |