[Bug c++/49759] New: std::streampos == int should be ambiguous

[mathieu.malaterre at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49759

           Summary: std::streampos == int should be ambiguous
           Product: gcc
           Version: 4.4.5
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: mathieu.malate...@gmail.com


I believe the following code should not compile:

#include <fstream>

int main()
{
  std::ofstream f( "bla.txt" );
  std::ifstream is( "bla.txt" );
  if( is.tellg() == 0 ) {}
  return 0;
}

the overload for 'operator==' is ambiguous and should be reported. Eg:


 line 7: error: more than one operator "==" matches these operands:
            built-in operator "arithmetic == arithmetic"
            function "std::operator==(const std::fpos<mbstate_t> &, const
                      std::fpos<mbstate_t> &)"
            operand types are: std::streampos == int
    if( is.tellg() == 0 ) {}
                   ^

or

error: ambiguous overload for 'operator==' in
'((std::istream*)is)->std::basic_istream<_CharT, _Traits>::tellg [with _CharT =
char, _Traits = std::char_traits<char>]() == 0'
note: candidates are: operator==(std::streamoff, int) <built-in>
/Developer/SDKs/MacOSX10.5.sdk/usr/include/c++/4.0.0/bits/postypes.h:138: note:
                bool std::fpos<_StateT>::operator==(const std::fpos<_StateT>&)
const [with _StateT = __mbstate_t]