[Boost-bugs] [Boost C++ Libraries] #12360: dead code detected by coverity in mersenne_twister

Subject: [Boost-bugs] [Boost C++ Libraries] #12360: dead code detected by coverity in mersenne_twister
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-07-29 12:42:17

#12360: dead code detected by coverity in mersenne_twister
---------------------------------------------+---------------------------
 Reporter:  James E. King, III <jim.king@…>  |      Owner:  no-maintainer
     Type:  Bugs                             |     Status:  new
Milestone:  To Be Determined                 |  Component:  random
  Version:  Boost 1.54.0                     |   Severity:  Optimization
 Keywords:                                   |
---------------------------------------------+---------------------------
 This is from boost 1.54 - it would be wise to re-test this on the
 development trunk to ensure it is still there before resolving it.  This
 would be considered a trivial performance optimization by removing a
 branch.

 {{{
     {
    assignment: Assigning: j = 623UL.
    const: At condition j < 623UL, the value of j must be equal to 623.
    dead_error_condition: The condition j < 623UL cannot be true.
 430        for(std::size_t j = n-1-unroll_extra2; j < n-1; j++) {
    CID 10152 (#1 of 1): Logically dead code (DEADCODE)dead_error_begin:
 Execution cannot reach this statement: y = (this->x[j] & 0x8000000....
 431            UIntType y = (x[j] & upper_mask) | (x[j+1] & lower_mask);
 432            x[j] = x[j-(n-m)] ^ (y >> 1) ^ ((x[j+1]&1) * a);
 433        }
 434    }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12360>
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