Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk?
-- >8 --
I noticed that in a couple of places we sometimes treat any TYPE_DECL of
lambda type as defining a lambda, which isn't always true since C++20:
in `using T = decltype([]{})`, T is not a lambda-declaration.
PR c++/106221
PR c++/110680
gcc/cp/ChangeLog:
* pt.cc (check_default_tmpl_args): Check this is actually a
lambda declaration and not just a typedef.
(push_template_decl): Likewise.
gcc/testsuite/ChangeLog:
* g++.dg/cpp2a/lambda-uneval19.C: New test.
Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
---
gcc/cp/pt.cc | 8 ++++----
gcc/testsuite/g++.dg/cpp2a/lambda-uneval19.C | 20 ++++++++++++++++++++
2 files changed, 24 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp2a/lambda-uneval19.C
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 7fa286698ef..0ffa0b53e26 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -5637,8 +5637,7 @@ check_default_tmpl_args (tree decl, tree parms, bool
is_primary,
local scope. */
return true;
- if ((TREE_CODE (decl) == TYPE_DECL
- && TREE_TYPE (decl)
+ if ((DECL_IMPLICIT_TYPEDEF_P (decl)
&& LAMBDA_TYPE_P (TREE_TYPE (decl)))
|| (TREE_CODE (decl) == FUNCTION_DECL
&& LAMBDA_FUNCTION_P (decl)))
@@ -5924,7 +5923,7 @@ push_template_decl (tree decl, bool is_friend)
template <typename T> friend void A<T>::f();
is not primary. */
;
- else if (TREE_CODE (decl) == TYPE_DECL && LAMBDA_TYPE_P (TREE_TYPE (decl)))
+ else if (DECL_IMPLICIT_TYPEDEF_P (decl) && LAMBDA_TYPE_P (TREE_TYPE (decl)))
/* Lambdas are not primary. */
;
else
@@ -6077,7 +6076,8 @@ push_template_decl (tree decl, bool is_friend)
else if (!ctx
|| TREE_CODE (ctx) == FUNCTION_DECL
|| (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
- || (TREE_CODE (decl) == TYPE_DECL && LAMBDA_TYPE_P (TREE_TYPE
(decl)))
+ || (DECL_IMPLICIT_TYPEDEF_P (decl)
+ && LAMBDA_TYPE_P (TREE_TYPE (decl)))
|| (is_friend && !(DECL_LANG_SPECIFIC (decl)
&& DECL_TEMPLATE_INFO (decl))))
{
diff --git a/gcc/testsuite/g++.dg/cpp2a/lambda-uneval19.C
b/gcc/testsuite/g++.dg/cpp2a/lambda-uneval19.C
new file mode 100644
index 00000000000..a9682cce6e6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/lambda-uneval19.C
@@ -0,0 +1,20 @@
+// { dg-do compile { target c++20 } }
+
+// PR c++/106221
+using T = decltype([](){});
+
+template<typename Opts>
+using foo = T;
+
+using bar = foo<int>;
+
+// PR c++/110680
+template <auto X = []{}>
+struct S {
+ auto f() { return X; }
+};
+
+template <class T>
+using C = decltype(S().f());
+
+using D = C<int>;
--
2.47.0
