[Bug c++/50220] New: [C++0x] ICE when capturing a by-reference template function argument in a lambda

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50220

             Bug #: 50220
           Summary: [C++0x] ICE when capturing a by-reference template
                    function argument in a lambda
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: grumbel@gmail.com


Following code causes an internal compiler error. Changing the function
argument from a reference to a value, makes the error go away, using a regular
struct instead of a template doesn't trigger it either:

$ cat internalbug.cpp
template<typename Foo> struct Foobar {};

void foobar(const Foobar<void>& obj)
{
  [obj](){}();
}

/* EOF */

$ g++-svn -std=c++0x -c internalbug.cpp -o internalbug.o 
internalbug.cpp: In lambda function:
internalbug.cpp:5:10: 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.

$ g++-svn --version
g++ (GCC) 4.7.0 20110828 (experimental)
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ uname -a
Linux duo 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:05:14 UTC 2011 i686
i686 i386 GNU/Linux

$ lsb_release -a
LSB Version:   
core-2.0-ia32:core-2.0-noarch:core-3.0-ia32:core-3.0-noarch:core-3.1-ia32:core-3.1-noarch:core-3.2-ia32:core-3.2-noarch:core-4.0-ia32:core-4.0-noarch:cxx-3.0-ia32:cxx-3.0-noarch:cxx-3.1-ia32:cxx-3.1-noarch:cxx-3.2-ia32:cxx-3.2-noarch:cxx-4.0-ia32:cxx-4.0-noarch:desktop-3.1-ia32:desktop-3.1-noarch:desktop-3.2-ia32:desktop-3.2-noarch:desktop-4.0-ia32:desktop-4.0-noarch:graphics-2.0-ia32:graphics-2.0-noarch:graphics-3.0-ia32:graphics-3.0-noarch:graphics-3.1-ia32:graphics-3.1-noarch:graphics-3.2-ia32:graphics-3.2-noarch:graphics-4.0-ia32:graphics-4.0-noarch:languages-3.2-ia32:languages-3.2-noarch:languages-4.0-ia32:languages-4.0-noarch:multimedia-3.2-ia32:multimedia-3.2-noarch:multimedia-4.0-ia32:multimedia-4.0-noarch:printing-3.2-ia32:printing-3.2-noarch:printing-4.0-ia32:printing-4.0-noarch:qt4-3.1-ia32:qt4-3.1-noarch
Distributor ID:    Ubuntu
Description:    Ubuntu 11.04
Release:    11.04
Codename:    natty