Re: Issue with Latest GDB on AIX with GCC-6.12

[Nitish Kumar Mishra <mishra.nitish.88@gmail.com>]

Hi all,
While sending the previous mail the statements got broken.
I am not sure if it is understandable. So, trying again :)

1. GDB with GCC-4.8.5, 32 bit mode, with or without static
    options : NOT WORKING.
2. GDB with GCC-4.8.5, 64 bit mode, with or without static
    options : WORKING FINE
3. GDB with GCC-6.1, 64 bit mode, with static options : NOT WORKING
4. GDB with GCC-6.1, 64 bit mode, without static options : COMPILATION ERROR.

P.S.: Static options means: -static-libstdc++ -static-libgcc
----------------

Thanks,
Nitish

On Thu, Feb 9, 2017 at 5:35 PM, Nitish Kumar Mishra
<mishra.nitish.88@gmail.com> wrote:
> Hi All !
> Here is my findings about GCC- 4.8.5 and 6.1:
>
>
> GCC-4.8.5 : 32 bit :::: (a) static linking to libstdc++
> -----------------> [process getting terminated (not working)]
>                                 (b) dynamic linking
> ------------------------------>  [process getting terminated (not
> working)]
>                   64 bit :::: (a) static linking to libstdc++
> -----------------> [working fine]
>                                 (b) dynamic linking
> -------------------------------> [working fine]
>
> GCC-6.1: 64 bit :::: (a) static linking to libstdc++
> ---------------------> [process getting terminated (not working)]
>                              (b) dynamic linking
> ----------------------------------> [Unable to compile (compilation
> error)]
>
>
> Above, static linking meant WITH option -static-libstdc++
> -static-libgcc and dynamic meant WITHOUT those options.
>
> --------------------------------------------
>
> Thanks,
> Nitish
>
>
> On Thu, Feb 9, 2017 at 10:21 AM, Nitish Kumar Mishra
> <mishra.nitish.88@gmail.com> wrote:
>> Hi David !
>>
>>>>GDB is linked with static libstdc++ and libgcc.
>>>>-static-libstdc++ -static-libgcc
>>>>Is your small test using those options?
>>
>> Yes, I used those static options. I am using readline library in my
>> test program and compiling it with gcc-6.1
>> like this:
>> g++ -g test.c -o test -static-libstdc++ -static-libgcc
>> -I/opt/freeware/include -lreadline
>> and the binary is working fine means I am able to catch the exceptions.
>>
>>>>Can you try linking GDB and testing GDB *without* those options?
>> ----Today I will be working on this---
>>
>> Thanks,
>> Nitish
>>
>>
>> On Wed, Feb 8, 2017 at 7:02 PM, David Edelsohn <dje.gcc@gmail.com> wrote:
>>> On Wed, Feb 8, 2017 at 7:06 AM, Pedro Alves <palves@redhat.com> wrote:
>>>> On 02/08/2017 06:16 AM, Nitish Kumar Mishra wrote:
>>>>
>>>>> I tried adding try/catch block earlier in throw_it and
>>>>> throw_exception_cxx functions
>>>>> but got no significant results.
>>>>> I had tried adding try catch block in these functions:
>>>>> kill_command
>>>>> command_handler
>>>>> command_line_handler
>>>>> execute_command
>>>>> throw_it
>>>>> throw_exception_cxx,
>>>>> but no progress. Output is exactly same as we got earlier (Other than
>>>>> extra frames for new
>>>>> try catch functions). None of the print statements in catch blocks for
>>>>> above functions worked.
>>>>
>>>> Eh, it sounds like _no_ exception catching works then?  I just
>>>> confirmed now that at least on GNU/Linux, GDB does not throw any
>>>> exception internally during startup.  This backtrace in question may
>>>> well not be special at all, and may be that _all_ exception catching
>>>> is broken.  I'd try experimenting with simple things like:
>>>>
>>>> try
>>>> {
>>>>   throw 1;
>>>> }
>>>> catch (...)
>>>> {
>>>>    printf (....);
>>>> }
>>>>
>>>> right at the start of gdb's main().  Not in a separately
>>>> compiled test program, but really inside gdb, to avoid
>>>> differences in how gdb vs the test program is built.
>>>>
>>>> It could also be that this is only triggered due to
>>>> GDB's binary size, hence not triggered in a small program -- I
>>>> recall that there was some trouble with the size of some sessions
>>>> and the linker in the AIX 7.1 box couldn't link gdb, or something
>>>> like that?  Maybe that's not fully/correctly sorted out.
>>>
>>> Nitish,
>>>
>>> GDB is linked with static libstdc++ and libgcc.
>>>
>>> -static-libstdc++ -static-libgcc
>>>
>>> Is your small test using those options?
>>>
>>> Can you try linking GDB and testing GDB *without* those options?
>>>
>>> Thanks, David