severity 211610 wishlist
reassign 211610 glibc
thanks
At Thu, 18 Sep 2003 18:17:42 -0500,
Andrés Roldán wrote:
> When trying to executing a binary with the __thread keywork, the program
> segfaults. Below is the output.
>
> [pts/0]
> [EMAIL PROTECTED]:~$ cat tls.c
> __thread int a;
>
> int
> main (void)
> {
> return a;
> }
> [pts/0]
> [EMAIL PROTECTED]:~$ gcc-3.3 -Wall -o tls tls.c
> [pts/0]
> [EMAIL PROTECTED]:~$ ./tls
> Segmentation fault (core dumped)
> [pts/0]
> [EMAIL PROTECTED]:~$ gdb tls core
> GNU gdb 5.3.90_2003-08-24-cvs-debian
> Copyright 2003 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-linux"...(no debugging symbols found)...
> Core was generated by `./tls'.
> Program terminated with signal 11, Segmentation fault.
> Reading symbols from /lib/libc.so.6...(no debugging symbols found)...done.
> Loaded symbols for /lib/libc.so.6
> Reading symbols from /lib/ld-linux.so.2...(no debugging symbols found)...done.
> Loaded symbols for /lib/ld-linux.so.2
> #0 0x08048344 in main ()
> (gdb) disas main
> Dump of assembler code for function main:
> 0x08048334 <main+0>: push %ebp
> 0x08048335 <main+1>: mov %esp,%ebp
> 0x08048337 <main+3>: sub $0x8,%esp
> 0x0804833a <main+6>: and $0xfffffff0,%esp
> 0x0804833d <main+9>: mov $0x0,%eax
> 0x08048342 <main+14>: sub %eax,%esp
> 0x08048344 <main+16>: mov %gs:0x0,%eax
This is because glibc's dl does not support tls currently on i386, so
%gs:0 does not setup correctly for this purpose.
Regards,
-- gotom
