Re: [Boost-users] Building andtesting smart pointers using HP-UX/G++

From: John Maddock (john_at_[hidden])
Date: 2005-12-07 06:06:03

> If you use -DBOOST_SP_USE_PTHREADS then the IA64-specific code I wrote
> for manipulating use counts will not be used. This worked on a
> dual-Itanium system under Linux, but I have not tested it on either
> the Itanium 2 or HP-UX. (Nor am I easily able to.) If you could use
> gdb to find exactly where the segmentation fault or bus error occurs,
> that might help me to track down the bug. You'll need to use the -g
> option to g++ in order for gdb to produce useful information.

Some more information: the problem does *not* occur on Red Hat Linux/IA64 or 
FreeBSD/IA64. The HP-UX problem you can reproduce/test for yourself by 
signing up for a HP-testdrive account and logging on to 
td176.testdrive.hp.com (see http://www.testdrive.hp.com/current.shtml).

But you'll see:

td176> g++ -I../../../ -g smart*.cpp
td176> gdb a.out
HP gdb 5.2 for HP Itanium (32 or 64 bit) and target HP-UX 11.2x.
Copyright 1986 - 2001 Free Software Foundation, Inc.
Hewlett-Packard Wildebeest 5.2 (based on GDB) is covered by the
GNU General Public License. Type "show copying" to see the conditions to
change it and/or distribute copies. Type "show warranty" for 
warranty/support.
..
(gdb) run
Starting program: /house/maddock/libs/smart_ptr/test/a.out
UDT with value 999888777 being destroyed
UDT with value 111222333 being destroyed

Program received signal SIGSEGV, Segmentation fault
  si_code: 1 - SEGV_MAPERR - Address not mapped to object.
0x400f021 in boost::detail::atomic_increment (pw=0x40012b94)
    at sp_counted_base_gcc_ia64.hpp:38
warning: Compilation directory is not absolute; could result in incorrect 
behavi
or.  Please report to HP.
38               "r"(pw));
(gdb) bt
#0  0x400f021 in boost::detail::atomic_increment (pw=0x40012b94)
    at sp_counted_base_gcc_ia64.hpp:38
#1  0x400f4e0 in boost::detail::sp_counted_base::add_ref_copy 
(this=0x40012b90)
    at sp_counted_base_gcc_ia64.hpp:117
#2  0x400f950 in boost::detail::shared_count::shared_count (this=0x7ffff44c,
    r=@0x7ffff444) at shared_count.hpp:216
#3  0x4010d50 in boost::shared_ptr<int>::boost::shared_ptr<int> (
    this=0x7ffff448) at shared_ptr.hpp:116
#4  0x400ad20:0 in test () at smart_ptr_test.cpp:165
#5  0x400ec30:0 in main () at smart_ptr_test.cpp:308

HTH, John.