Re: storage error: stack overflow

[hreba <f_hreba@yahoo.com.br>]

On 08/12/2015 07:57 AM, Simon Wright wrote:
> hreba <f_hreba@yahoo.com.br> writes:
>
>> I am developing a program on 3 computers in parallel (depending on
>> where I am). On 2 of them the executable works as expected, on one I
>> get:
>>
>> raised PROGRAM_ERROR ; adjust/finalize raised STORAGE_ERROR: stack
>> overflow (or erroneous memory access)
>
>> How can I find out what is wrong?
>
> Use the debugger and 'catch exception storage_error'?
>
> I'd think it's more likely an erroneous memory access than a stack
> overflow. As I remember, GNAT catches a SIGSEGV and does its best to
> work out what the problem was, but at that level it can be hard to tell.
>

The name of my program is "sos". Calling it with gdb:

-----------------------------------------------------
~/Projects/SOS/Exec $ gdb sos
<some infos about gdb>
Reading symbols from sos...done
(gdb) catch exception storage_error
Unable to insert catchpoint. Try to start the program first.
(gdb) run
Starting program: /home/frank/Projects/SOS/Exec/sos
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1"

(process:2365): Gtk-WARNING **: Locale not supported by C library.
         Using the fallback 'C' locale

Program received signal SIGSEGV, segmentation fault.
0x00007ffff627a1a0 in ada.strings.unbounded.reference () from 
/usr/lib/x86_64-linux-gnu/libgnat-4.6.so.1
(gdb) catch exception storage_error
Your Ada runtime appears to be missing some debug information.
Cannot insert Ada exception catchpoint in this configuration.
---------------------------------------------------------

I compiled my program for debugging, but the debug information perhaps 
is missing in libgnat. Anyway, the problem has to do with 
Ada.Strings.Unbounded. For more, see my answer to Emmanuel Briot.

-- 
Frank Hrebabetzky		+55 / 48 / 3235 1106
Florianopolis, Brazil