[C++ PATCH] Fix ICE in cxx_incomplete_type_diagnostic (PR c++/51429)

[Jakub Jelinek]

Hi!

This testcase regressed recently when Paolo added the user friendlier
invalid use of member function vs. invalid use of member distinction,
when TREE_OPERAND (value, 1) is BASELINK, DECL_FUNCTION_MEMBER_P on it
dies with a checking ICE.
The following patch calls get_first_fn if it is overloaded_fn.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2011-12-07  Jakub Jelinek  <ja...@redhat.com>

        PR c++/51429
        * typeck2.c (cxx_incomplete_type_diagnostic): Don't
        ICE if TREE_OPERAND (value, 1) is overloaded.

        * g++.dg/parse/error45.C: New test.

--- gcc/cp/typeck2.c.jj 2011-11-07 12:40:45.000000000 +0100
+++ gcc/cp/typeck2.c    2011-12-07 15:31:30.506795286 +0100
@@ -428,15 +428,20 @@ cxx_incomplete_type_diagnostic (const_tr
 
     case OFFSET_TYPE:
     bad_member:
-      if (DECL_FUNCTION_MEMBER_P (TREE_OPERAND (value, 1))
-         && ! flag_ms_extensions)
-       emit_diagnostic (diag_kind, input_location, 0,
-                        "invalid use of member function "
-                        "(did you forget the %<()%> ?)");
-      else
-       emit_diagnostic (diag_kind, input_location, 0,
-                        "invalid use of member "
-                        "(did you forget the %<&%> ?)");
+      {
+       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)
+         emit_diagnostic (diag_kind, input_location, 0,
+                          "invalid use of member function "
+                          "(did you forget the %<()%> ?)");
+       else
+         emit_diagnostic (diag_kind, input_location, 0,
+                          "invalid use of member "
+                          "(did you forget the %<&%> ?)");
+      }
       break;
 
     case TEMPLATE_TYPE_PARM:
--- gcc/testsuite/g++.dg/parse/error45.C.jj     2011-12-07 15:45:28.732286838 
+0100
+++ gcc/testsuite/g++.dg/parse/error45.C        2011-12-07 15:44:20.000000000 
+0100
@@ -0,0 +1,9 @@
+// PR c++/51429
+// { dg-do compile }
+
+struct A
+{
+  void foo (double);
+  void foo (int);
+  A () { foo = 0; }    // { dg-error "invalid use of member function" }
+};

        Jakub