c++: Fix ICE diagnosing incomplete type of overloaded function set [PR98356]

In the linked PR the result of 'get_first_fn' is a USING_DECL against
the template parameter, to be filled in on instantiation. But we don't
actually need to get the first set of the member functions: it's enough
to know that we have a (possibly overloaded) member function at all.

	PR c++/98356

gcc/cp/ChangeLog:

	* typeck2.cc (cxx_incomplete_type_diagnostic): Don't assume
	'member' will be a FUNCTION_DECL (or something like it).

gcc/testsuite/ChangeLog:

	* g++.dg/pr98356.C: New test.

Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>

diff --git a/gcc/cp/typeck2.cc b/gcc/cp/typeck2.cc
index 9608bdccd8b272caf7e2b2f9ed4802f839d4cc3c..31198b2f9f584bde4d2d85e5cc2f19a24e119b46 100644 (file)
--- a/gcc/cp/typeck2.cc
+++ b/gcc/cp/typeck2.cc
@@ -350,16 +350,15 @@ cxx_incomplete_type_diagnostic (location_t loc, const_tree value,
     bad_member:
       {
        tree member = TREE_OPERAND (value, 1);
-       if (is_overloaded_fn (member))
-         member = get_first_fn (member);
-
-       if (DECL_FUNCTION_MEMBER_P (member)
-           && ! flag_ms_extensions)
+       if (is_overloaded_fn (member) && !flag_ms_extensions)
          {
            gcc_rich_location richloc (loc);
            /* If "member" has no arguments (other than "this"), then
               add a fix-it hint.  */
-           if (type_num_arguments (TREE_TYPE (member)) == 1)
+           member = MAYBE_BASELINK_FUNCTIONS (member);
+           if (TREE_CODE (member) == FUNCTION_DECL
+               && DECL_OBJECT_MEMBER_FUNCTION_P (member)
+               && type_num_arguments (TREE_TYPE (member)) == 1)
              richloc.add_fixit_insert_after ("()");
            complained = emit_diagnostic (diag_kind, &richloc, 0,
                             "invalid use of member function %qD "

diff --git a/gcc/testsuite/g++.dg/pr98356.C b/gcc/testsuite/g++.dg/pr98356.C
new file mode 100644 (file)
index 0000000..acea238
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr98356.C
@@ -0,0 +1,9 @@
+// PR c++/98356
+// { dg-do compile { target c++11 } }
+
+template <template <typename> class T> struct S {
+  using A = T<int>;
+  using A::foo;
+  void foo ();
+  void bar () {foo.}  // { dg-error "invalid use of member function" }
+};