Description of problem:
Consider the following C++ code:

[code]
#include <iostream>

int main(int argc, char* argv[])
{
    std::cout << "Hello World!\n"; 
}
[/code]

This fails to compile.

Version-Release number of selected component (if applicable):

$ yum info clang
Name        : clang
Arch        : x86_64
Version     : 2.8
Release     : 11.fc15
Size        : 16 M
Repo        : installed
From repo   : fedora
Summary     : A C language family front-end for LLVM
URL         : http://llvm.org/
License     : NCSA
Description : clang: noun
            :     1. A loud, resonant, metallic sound.
            :     2. The strident call of a crane or goose.
            :     3. C-language family front-end toolkit.
            : 
            : The goal of the Clang project is to create a new C, C++, Objective C
            : and Objective C++ front-end for the LLVM compiler. Its tools are built
            : as libraries and designed to be loosely-coupled and extensible.


How reproducible:
Always.

Steps to Reproduce:
1. yum groupinstall "Development Tools"
2. yum install clang
3. Create main.cpp with the above content.
4. Try to compile this file with "clang main.cpp"
  
Actual results:
The compilation fails with the following error messages:

In file included from main.cpp:1:
In file included from /usr/include/c++/4.6.0/iostream:39:
In file included from /usr/include/c++/4.6.0/ostream:39:
In file included from /usr/include/c++/4.6.0/ios:40:
In file included from /usr/include/c++/4.6.0/bits/char_traits.h:40:
/usr/include/c++/4.6.0/bits/stl_algobase.h:378:43: error: unexpected type name '_ValueTypeI': expected expression
      const bool __simple = (__is_trivial(_ValueTypeI)
                                          ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:383:40: error: non-type template argument of type 'bool const' is not an integral constant expression
      return std::__copy_move<_IsMove, __simple,
                                       ^~~~~~~~
/usr/include/c++/4.6.0/bits/stl_algobase.h:573:43: error: unexpected type name '_ValueType1': expected expression
      const bool __simple = (__is_trivial(_ValueType1)
                                          ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:578:49: error: non-type template argument of type 'bool const' is not an integral constant expression
      return std::__copy_move_backward<_IsMove, __simple,
                                                ^~~~~~~~
/usr/include/c++/4.6.0/bits/stl_algobase.h:731:32: error: expected ';' in 'for' statement specifier
      for (__decltype(__n + 0) __niter = __n;
                               ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:732:5: error: use of undeclared identifier '__niter'
           __niter > 0; --__niter, ++__first)
           ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:732:20: error: use of undeclared identifier '__niter'
           __niter > 0; --__niter, ++__first)
                          ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:732:27: error: expected ')'
           __niter > 0; --__niter, ++__first)
                                 ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:731:11: note: to match this '('
      for (__decltype(__n + 0) __niter = __n;
          ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:743:32: error: expected ';' in 'for' statement specifier
      for (__decltype(__n + 0) __niter = __n;
                               ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:744:5: error: use of undeclared identifier '__niter'
           __niter > 0; --__niter, ++__first)
           ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:744:20: error: use of undeclared identifier '__niter'
           __niter > 0; --__niter, ++__first)
                          ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:744:27: error: expected ')'
           __niter > 0; --__niter, ++__first)
                                 ^
/usr/include/c++/4.6.0/bits/stl_algobase.h:743:11: note: to match this '('
      for (__decltype(__n + 0) __niter = __n;
          ^
12 errors generated.

Expected results:
The compilation should be successful, it should not generate error messages and output a binary that prints "Hello World!" to stdout.

Additional info:
As a former Ubuntu user, I faced this very same issue before. If I understood correctly, the root cause of the problem is that GCC 4.6 ships with a standard library implementation that uses many C++0x features that clang 2.8 does not understand. In Ubuntu, there is a libstdc++4.5 package. Having that installed on that system, I was able to use clang before.