[Bug c++/53503] New: [4.7 Regression] [C++0x] unexpected AST of kind ltgt_expr

["liling at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53503

             Bug #: 53503
           Summary: [4.7 Regression] [C++0x] unexpected AST of kind
                    ltgt_expr
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: liling@gmail.com


Created attachment 27510
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27510
Preporcessed source

G++ 4.7 can't compile a one-line file with both -std=c++0x and
-fno-trapping-math:

$ cat a.cpp
#include <cmath>
$ g++ -fno-trapping-math -std=c++0x -c a.cpp
In file included from a.cpp:1:0:
/usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath: In
function âconstexpr bool std::islessgreater(float, float)â:
/usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath:764:47:
sorry, unimplemented: unexpected AST of kind ltgt_expr
/usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath:764:
confused by earlier errors, bailing out
Preprocessed source stored into /tmp/ccGqxqjD.out file, please attach this to
your bugreport.

I was using GCC 4.7.0 20120507 on Fedora 17.