c++: fix bogus error with xobj member function [PR125330]

In this test since r17-472 we issue a bogus "not declared in this scope"
error when parsing the requires because we failed to pushdecl.  Xobj
parameters reuse the default argument field (in _parameter_declaration)
so we also have to check this_identifier.

	PR c++/125330

gcc/cp/ChangeLog:

	* parser.cc (cp_parser_parameter_declaration_list): Also
	pushdecl when parameter->default_argument is this_identifier.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp23/explicit-obj-basic8.C: New test.

Reviewed-by: Jason Merrill <jason@redhat.com>

diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 1ab462160da8996990eaa24cd616c7049d801c33..0c78c437019fb73bf4d850e9ca9b51334b1b6e08 100644 (file)
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -28347,7 +28347,8 @@ cp_parser_parameter_declaration_list (cp_parser* parser,
          /* If we saw a default argument, we've already pushed this decl.
             (An ill-formed default argument should have been parsed to
             error_mark_node.)  */
-         else if (!parameter->default_argument)
+         else if (!parameter->default_argument
+                  || parameter->default_argument == this_identifier)
            decl = pushdecl (decl);
        }
 

diff --git a/gcc/testsuite/g++.dg/cpp23/explicit-obj-basic8.C b/gcc/testsuite/g++.dg/cpp23/explicit-obj-basic8.C
new file mode 100644 (file)
index 0000000..6824bcb
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp23/explicit-obj-basic8.C
@@ -0,0 +1,8 @@
+// PR c++/125330
+// { dg-do compile { target c++23 } }
+
+struct T {
+  template<typename Self>
+  void foo(this Self const &x) requires requires { x.bar(); }
+    { x.bar(); }
+};