Here we ICE with -Wmismatched-tags on something like
template <class T>
bool B<T, enable_if_t<is_class_v<class T::foo>>>;
Specifically, the "class T::foo" bit. There, class_decl_loc_t::add gets
a TYPENAME_TYPE as TYPE, rather than a class/union type, so checking
TYPE_BEING_DEFINED will crash. I think it's OK to allow a TYPENAME_TYPE to
slip into that function; we just shouldn't consider the 'class' tag redundant
(which works as a 'typename'). In fact, every other compiler *requires* it.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
PR c++/105725
gcc/cp/ChangeLog:
* parser.cc (class_decl_loc_t::add): Check CLASS_TYPE_P.
gcc/testsuite/ChangeLog:
* g++.dg/warn/Wmismatched-tags-10.C: New test.
---
gcc/cp/parser.cc | 5 +++--
gcc/testsuite/g++.dg/warn/Wmismatched-tags-10.C | 10 ++++++++++
2 files changed, 13 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/warn/Wmismatched-tags-10.C
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 4b9859543ed..9a9f859974a 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -33666,7 +33666,8 @@ class_decl_loc_t::add (cp_parser *parser, location_t
key_loc,
bool key_redundant = (!def_p && !decl_p
&& (decl == type_decl
|| TREE_CODE (decl) == TEMPLATE_DECL
- || TYPE_BEING_DEFINED (type)));
+ || (CLASS_TYPE_P (type)
+ && TYPE_BEING_DEFINED (type))));
if (key_redundant
&& class_key != class_type
@@ -33704,7 +33705,7 @@ class_decl_loc_t::add (cp_parser *parser, location_t
key_loc,
}
else
{
- /* TYPE was previously defined in some unknown precompiled hdeader.
+ /* TYPE was previously defined in some unknown precompiled header.
Simply add a record of its definition at an unknown location and
proceed below to add a reference to it at the current location.
(Declarations in precompiled headers that are not definitions
diff --git a/gcc/testsuite/g++.dg/warn/Wmismatched-tags-10.C
b/gcc/testsuite/g++.dg/warn/Wmismatched-tags-10.C
new file mode 100644
index 00000000000..d7e10743bb4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wmismatched-tags-10.C
@@ -0,0 +1,10 @@
+// PR c++/105725
+// { dg-do compile { target c++14 } }
+// { dg-options "-Wall -Wmismatched-tags" }
+
+template <bool> struct enable_if;
+template <bool Cond> using enable_if_t = typename enable_if<Cond>::type;
+template <typename> bool is_class_v;
+template <class, class> bool B;
+template <class T>
+bool B<T, enable_if_t<is_class_v<class T::foo>>>;
base-commit: de57440858591a88e8fd7ba2505ca54546c86021
--
2.36.1
