id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
5187	uuid\seed_rng.hpp sha1_random_digest_state_ not random	qiaozhiqiang@…	Andy Tompkins	"boost_1_45_0\boost\uuid\seed_rng.hpp

static unsigned int * sha1_random_digest_state_()
    {
        // intentionally left uninitialized
        // ERROR 1: not uninitialized! static value always zero all.
        // ERROR 2: always return the same pointer of static value
        // should delete 'static'
        static unsigned int state[ 5 ];
        return state;
    }


unsigned int * ps = sha1_random_digest_state_();

        unsigned int state[ 5 ];

        std::memcpy( state, ps, sizeof( state ) ); // harmless data race

// ERROR 1: not uninitialized! static value always zero all.
// so state is all zero
        sha.process_bytes( (unsigned char const*)state, sizeof( state ) );
         
// ERROR 2: always return the same pointer of static value
//  so ps is same ( ps === ps)
        sha.process_bytes( (unsigned char const*)&ps, sizeof( ps ) );

namespace boost {
namespace uuids {
namespace detail {

// should this be part of Boost.Random?
class seed_rng
{
static unsigned int * sha1_random_digest_state_()
    {
        // intentionally left uninitialized
        static unsigned int state[ 5 ];
        return state;
    }

    void sha1_random_digest_()
    {
        boost::uuids::detail::sha1 sha;

        unsigned int * ps = sha1_random_digest_state_();

        unsigned int state[ 5 ];
        std::memcpy( state, ps, sizeof( state ) ); // harmless data race

        sha.process_bytes( (unsigned char const*)state, sizeof( state ) );
        sha.process_bytes( (unsigned char const*)&ps, sizeof( ps ) );"	Bugs	closed	To Be Determined	uuid	Boost 1.45.0	Problem	invalid	seed_rng