[Bug c++/46117] New: [4.6 Regression] ICE: SIGSEGV in add_function_candidate (call.c:1630) on invalid typename usage

["zsojka at seznam dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46117

           Summary: [4.6 Regression] ICE: SIGSEGV in
                    add_function_candidate (call.c:1630) on invalid
                    typename usage
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz


Created attachment 22106
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22106
reduced testcase

Compiler output:
$ gcc pr46117.C 
pr46117.C:3:15: error: expected nested-name-specifier before 'int'
pr46117.C:3:15: error: two or more data types in declaration of 'parameter'
pr46117.C:8:3: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.


valgrind output:
testcase.C:3:13: error: expected nested-name-specifier before 'int'
testcase.C:3:13: error: two or more data types in declaration of 'parameter'
==24080== Invalid read of size 2
==24080==    at 0x4A8823: add_function_candidate (call.c:1630)
==24080==    by 0x4A58B3: add_candidates (call.c:4254)
==24080==    by 0x4AB8A3: build_new_method_call (call.c:6528)
==24080==    by 0x5BBB24: locate_fn_flags (method.c:826)
==24080==    by 0x5BEEB5: synthesized_method_walk (method.c:1183)
==24080==    by 0x5BF839: implicitly_declare_fn (method.c:1433)
==24080==    by 0x5C0ACA: lazily_declare_fn (method.c:1634)
==24080==    by 0x5C5354: lookup_fnfields_1 (search.c:1360)
==24080==    by 0x5C8653: lookup_field_r (search.c:1032)
==24080==    by 0x5C5918: dfs_walk_all (search.c:1542)
==24080==    by 0x5C5A97: lookup_member (search.c:1206)
==24080==    by 0x5C5CCA: lookup_fnfields (search.c:1288)
==24080==  Address 0x0 is not stack'd, malloc'd or (recently) free'd
==24080== 
testcase.C:8:3: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Full backtrace is quite long, so I am posting just this reduced one

Tested revisions:
r165768 - crash
r163636 - crash
r161659 - OK