[Bug libstdc++/13831] New: Unused variable in basic_filebuf::underflow

[bangerth at dealii dot org]

In bits/fstream.tcc, we have this function: 
----------------------- 
  template<typename _CharT, typename _Traits> 
    typename basic_filebuf<_CharT, _Traits>::int_type  
    basic_filebuf<_CharT, _Traits>:: 
    underflow() 
    { 
      int_type __ret = traits_type::eof(); 
      const bool __testin = this->_M_mode & ios_base::in; 
      const bool __testout = this->_M_mode & ios_base::out; 
      if (__testin && !_M_writing) 
 
..... 
-------------------- 
The problem is that __testout is not used anywhere in this function. 
I don't know whether that's a bug, but it's a nuisance when reducing 
testcases: when one strips off all #line markers in preprocessed 
sources and compiles with warnings on, then one also gets to see 
warnings for this. 
 
W.

-- 
           Summary: Unused variable in basic_filebuf::underflow
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bangerth at dealii dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13831