[Boost-bugs] [Boost C++ Libraries] #6118: Uuid random_generator compiles with warnings by GCC

Subject: [Boost-bugs] [Boost C++ Libraries] #6118: Uuid random_generator compiles with warnings by GCC
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-11-12 16:24:06

#6118: Uuid random_generator compiles with warnings by GCC
---------------------------------------------+------------------------------
 Reporter:  Vasily Sukhanov <basil@…>        |       Owner:  atompkins
     Type:  Bugs                             |      Status:  new      
Milestone:  To Be Determined                 |   Component:  uuid     
  Version:  Boost 1.47.0                     |    Severity:  Problem  
 Keywords:  warning                          |  
---------------------------------------------+------------------------------
 uuids::random_generator constructor emits warning when compiled with GCC:
 >g++ -O2 -Wall -Werror uuidTest.cpp[[BR]]

 On Linux x86_64, gcc 4.5.2 output is

 /home/vasily/boost_1_47_0/boost/uuid/seed_rng.hpp: In member function
 ‘void boost::uuids::detail::seed_rng::sha1_random_digest_()’:
 /home/vasily/boost_1_47_0/boost/uuid/seed_rng.hpp:152:53: error: ignoring
 return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared
 with attribute warn_unused_result

 Cross gcc 4.5.3 (Linux -> Solaris) and gcc 4.6.1 (Linux -> AIX) produce

 In file included from testBoostUuid.cpp:3:0:
 /emc/sukhav/cross/boost_1_47_0/boost/uuid/seed_rng.hpp: In constructor
 ‘boost::uuids::basic_random_generator<UniformRandomNumberGenerator>::basic_random_generator()
 [with UniformRandomNumberGenerator =
 boost::random::mersenne_twister_engine<unsigned int, 32ul, 624ul, 397ul,
 31ul, 2567483615u, 11ul, 4294967295u, 7ul, 2636928640u, 15ul, 4022730752u,
 18ul, 1812433253u>]’:
 /emc/sukhav/cross/boost_1_47_0/boost/uuid/seed_rng.hpp:243:34: error:
 ‘end.boost::uuids::detail::generator_iterator<boost::uuids::detail::seed_rng>::m_value’
 may be used uninitialized in this function [-Werror=uninitialized]

 Latter warning is regression. Compilation passes with boost 1.46.1.
 Probably, it's caused by some changes in Random library.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/6118>
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