views:

71

answers:

1

Trying to run a C++ program, I get segmentation faults which appear to be specific to NetBSD. Bert Hubert wrote the simple test program (at the end of this message) and, indeed, it crashes only on NetBSD.

% uname -a
NetBSD golgoth 5.0.1 NetBSD 5.0.1 (GENERIC) #0: Thu Oct  1 15:46:16 CEST 2009
+stephane@golgoth:/usr/obj/sys/arch/i386/compile/GENERIC i386

% g++ --version
g++ (GCC) 4.1.3 20080704 prerelease (NetBSD nb2 20081120)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

% gdb thread-local-storage-powerdns
GNU gdb 6.5
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386--netbsdelf"...
(gdb) run
Starting program: /home/stephane/Programmation/C++/essais/thread-local-storage-powerdns

Program received signal SIGSEGV, Segmentation fault.
0x0804881b in main () at thread-local-storage-powerdns.cc:20
20        t_a = new Bogo('a');
(gdb)

On other Unix, it works fine. Is there a known issue in NetBSD with C++ thread-local storage?

#include <stdio.h>


class Bogo
{
public:

  explicit Bogo(char a)
  {
 d_a = a;
  }

  char d_a;
};

__thread Bogo* t_a;

int main()
{
  t_a = new Bogo('a');

  Bogo* b = t_a;

  printf("%c\n", b->d_a);
}
+1  A: 

NetBSD does not support thread-local storage. Most of the other BSDs do however.

Yann Ramin
Is there a clean way to detect that at compile-time or run-time, to produce a better error message? An existing autoconf rule, for instance?
bortzmeyer
Any pointer to NetBSD documentation about that? I was not able to find it with search engines.
bortzmeyer
http://www.mail-archive.com/[email protected]/msg04644.html is the best I could find.
Joe