[Boost-bugs] [Boost C++ Libraries] #1531: segfault in dynamic_bitset::reference assign operator

Subject: [Boost-bugs] [Boost C++ Libraries] #1531: segfault in dynamic_bitset::reference assign operator
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2007-12-20 20:37:31

#1531: segfault in dynamic_bitset::reference assign operator
-------------------------------------+--------------------------------------
 Reporter:  ben.collins_at_[hidden]      |       Owner:  jsiek         
     Type:  Bugs                     |      Status:  new           
Milestone:  Boost 1.35.0             |   Component:  dynamic_bitset
  Version:  Boost Development Trunk  |    Severity:  Problem       
 Keywords:  dynamic_bitset           |  
-------------------------------------+--------------------------------------
 I will of course take a look at this later (i.e., I've go to stop here and
 do the work I get paid to do), but for now, this will serve as a heads up
 to any one who's interested.  Perhaps I'm not initializing {{{bset}}}
 correctly, but I couldn't easily tell that from the headers or the online
 documentation.

 test code:

 {{{
 $ cat bitset.cpp
 #include <iostream>
 #include <string>
 #include <boost/dynamic_bitset.hpp>

 int main()
 {
   boost::dynamic_bitset<> bset;

   bset[0] = true;
   bset[0] = false;

   return 0;
 }

 }}}

 compile + gdb session:

 {{{
 $ g++ -I ~/local/include/boost-1_35/ -o bitset bitset.cpp
 $ ./bitset
 Segmentation fault
 $ g++ -g -I ~/local/include/boost-1_35/ -o bitset bitset.cpp
 $ gdb bitset
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 libthread_db library "/lib/libthread_db.so.1".

 (gdb) r
 Starting program: /users/bcollins/test/C++/bitset

 Program received signal SIGSEGV, Segmentation fault.
 0x08048877 in boost::dynamic_bitset<unsigned long, std::allocator<unsigned
 long> >::reference::do_set (this=0xbf856240)
     at /users/bcollins/local/include/boost-
 1_35/boost/dynamic_bitset/dynamic_bitset.hpp:115
 115             void do_set() { m_block |= m_mask; }
 (gdb) bt
 #0  0x08048877 in boost::dynamic_bitset<unsigned long,
 std::allocator<unsigned long> >::reference::do_set (this=0xbf856240)
     at /users/bcollins/local/include/boost-
 1_35/boost/dynamic_bitset/dynamic_bitset.hpp:115
 #1  0x080488a3 in boost::dynamic_bitset<unsigned long,
 std::allocator<unsigned long> >::reference::do_assign (this=0xbf856240,
 x=true)
     at /users/bcollins/local/include/boost-
 1_35/boost/dynamic_bitset/dynamic_bitset.hpp:118
 #2  0x080488d1 in boost::dynamic_bitset<unsigned long,
 std::allocator<unsigned long> >::reference::operator= (this=0xbf856240,
 x=true)
     at /users/bcollins/local/include/boost-
 1_35/boost/dynamic_bitset/dynamic_bitset.hpp:103
 #3  0x080486c9 in main () at bitset.cpp:9
 (gdb) f 0
 #0  0x08048877 in boost::dynamic_bitset<unsigned long,
 std::allocator<unsigned long> >::reference::do_set (this=0xbf856240)
     at /users/bcollins/local/include/boost-
 1_35/boost/dynamic_bitset/dynamic_bitset.hpp:115
 115             void do_set() { m_block |= m_mask; }
 (gdb) p m_block
 $1 = (long unsigned int &) @0x0: Cannot access memory at address 0x0
 (gdb)
 }}}

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/1531>
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