[Bug libstdc++/58938] New: [4.7/4.8/4.9 Regression] std::exception_ptr is missing on architectures with incomplete atomic int support

[rafal at rawicki dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58938

            Bug ID: 58938
           Summary: [4.7/4.8/4.9 Regression] std::exception_ptr is missing
                    on architectures with incomplete atomic int support
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rafal at rawicki dot org

In file ./libstdc++-v3/libsupc++/exception (also in trunk) bits/exception_ptr.h
is included conditionally:

#if (__cplusplus >= 201103L) && (ATOMIC_INT_LOCK_FREE > 1)
#include <bits/exception_ptr.h>
#include <bits/nested_exception.h>
#endif

On ARM architecture ATOMIC_INT_LOCK_FREE is set to 1. That leads to losing some
functionality of standard library for no good reason.