system_error.hpp doesn't compile without exceptions

[ruslan-b <RusBaratov@…>]

Compiling with gcc flag -fno-exceptions failed:

..\boost_1_51_0\boost\system\system_error.hpp:70: error: exception handling disabled, use -fexceptions to enable

code:

    inline const char * system_error::what() const throw()
    // see http://www.boost.org/more/error_handling.html for lazy build rationale
    {
      if ( m_what.empty() )
      {
        try
        {
          m_what = this->std::runtime_error::what();
          if ( !m_what.empty() ) m_what += ": ";
          m_what += m_error_code.message();
        }
        catch (...) { return std::runtime_error::what(); }
      }
      return m_what.c_str();
    }

[viboes]

#7149 system failed to compile with BOOST_NO_EXCEPTIONS defined when -fno-exceptions is NOT used