[Bug libstdc++/56011] New: [C++11] std::atomic<bool> and std::atomic_bool miss volatile assignment operator overload

["daniel.kruegler at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56011

             Bug #: 56011
           Summary: [C++11] std::atomic<bool> and std::atomic_bool miss
                    volatile assignment operator overload
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: daniel.kruegler@googlemail.com


Using gcc 4.8.0 trunk the following program - compiled with the flags

-pedantic-errors -std=c++11 -Wall

is rejected:

//----------------------------------
#include <atomic>

int main() {
  volatile std::atomic<bool> ab1;
  ab1 = true;
  volatile std::atomic_bool ab2;
  ab2 = true;
}
//----------------------------------

"main.cpp||In function 'int main()':|
main.cpp|5|error: ambiguous overload for 'operator=' (operand types are
'volatile std::atomic<bool>' and 'bool')|
main.cpp|5|note: candidates are:|
[..]gcc\include\c++\4.8.0\atomic|485|note: std::atomic<bool>&
std::atomic<bool>::operator=(const std::atomic<bool>&) volatile <deleted>|
[..]gcc\include\c++\4.8.0\atomic|64|note: std::atomic_bool&
std::atomic_bool::operator=(const std::atomic_bool&) volatile <deleted>|
main.cpp|7|error: use of deleted function 'std::atomic_bool&
std::atomic_bool::operator=(const std::atomic_bool&) volatile'|
[..]gcc\include\c++\4.8.0\atomic|64|error: declared here|
"

The problem is due to the missing overload (part of the specification):

bool operator=(bool __i) volatile noexcept;