[Boost-bugs] [Boost C++ Libraries] #9596: "logical ‘and’ of mutually exclusive tests is always false" error in random/linear_congruential.hpp

Subject: [Boost-bugs] [Boost C++ Libraries] #9596: "logical ‘and’ of mutually exclusive tests is always false" error in random/linear_congruential.hpp
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-01-20 14:57:00

#9596: "logical ‘and’ of mutually exclusive tests is always false" error in
random/linear_congruential.hpp
------------------------------+---------------------------
 Reporter:  a0smucig@…        |      Owner:  no-maintainer
     Type:  Patches           |     Status:  new
Milestone:  To Be Determined  |  Component:  random
  Version:  Boost 1.55.0      |   Severity:  Optimization
 Keywords:                    |
------------------------------+---------------------------
 There is a line in random/linear_congruential.hpp at line 136 which seems
 to work, but may be a bit wrong. It may definitely be my somewhat small
 knowledge of how the compiler works, but shouldn't this: if(_x <= 0 && _x
 != 0) be equal to if(_x < 0). This line throws an error with the -Werror
 flag set in gcc 4.7.2: with "logical ‘and’ of mutually exclusive tests is
 always false [-Werror=logical-op]". These are not mutually exclusive, so
 the compiler may be wrong, but the question still remains if this could be
 done better.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9596>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.