[Boost-bugs] [Boost C++ Libraries] #12363: int_adapter is_signed should be const

Subject: [Boost-bugs] [Boost C++ Libraries] #12363: int_adapter is_signed should be const
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-07-29 13:28:52

#12363: int_adapter is_signed should be const
---------------------------------------------+------------------------
 Reporter:  James E. King, III <jim.king@…>  |      Owner:  az_sw_dude
     Type:  Bugs                             |     Status:  new
Milestone:  To Be Determined                 |  Component:  date_time
  Version:  Boost 1.54.0                     |   Severity:  Cosmetic
 Keywords:                                   |
---------------------------------------------+------------------------
 In int_adapter at lines 171 to 183, with coverity comments:

 {{{
 171 bool operator<(const int& rhs) const
 172  {
 173    // quiets compiler warnings
    assignment: Assigning: is_signed = true.
 174    bool is_signed = std::numeric_limits<int_type>::is_signed;
    const: At condition is_signed, the value of is_signed must be equal to
 1.
    dead_error_condition: The condition !is_signed cannot be true.
 175    if(!is_signed)
 176    {
    CID 10153 (#1 of 1): 'Constant' variable guards dead code
 (DEADCODE)dead_error_line: Execution cannot reach this statement: if
 (boost::date_time::int_a....
    Local variable is_signed is assigned only once, to a constant value,
 making it effectively constant throughout its scope. If this is not the
 intent, examine the logic to see if there is a missing assignment that
 would make is_signed not remain constant. Otherwise, declaring is_signed
 as const will suppress this defect.
 177      if(is_neg_inf(value_) && rhs == 0)
 178      {
 179        return true;
 180      }
 181    }
 182    return (compare(rhs) == -1);
 183  }
 }}}

 Coverity picks this up indicating that if is_signed was const (or perhaps
 even better in C++11 a constexpr?) it would allow the compiler to optimize
 better.

 This is in the development trunk back to at least 1.54.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12363>
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