Re: Autoconf & gnat Help Needed

["Alex R. Mosteo" <alejandro@mosteo.invalid>]

Warren wrote:

> Stephen Leake expounded in news:82fx2lm74h.fsf@stephe-leake.org:
> 
>> Warren <ve3wwg@gmail.com> writes:
>> 
>>> Vadim Godunko expounded in news:5867de55-7ca2-4c64-a72f-d2343153eef0
>>> @k36g2000yqn.googlegroups.com:
>>>
>>>> On Apr 23, 5:44 pm, Warren <ve3...@gmail.com> wrote:
>>>>>
>>>>> For a basic interpreter, making use of ncurses, libgmp, libgsl,
>>>>> and PostgreSQL etc., it is unavoidable. :)  I tried to avoid C++
>>>>> like the plague, but ncurses requires a C++ main, if GNAT exceptions
>>>>> are to work correctly. I'm not sure of the details why, but a GNAT
>>>>> exception + ncurses and a C or gnat main leads to an abort.
>>>>> Switching to a C++ main program has corrected that.
>>>>>
>>>> Did you try to pass -shared to gnatbind?
>>>
>>> No, but is that really relevant?
>>>
>>> The problem was not library linkage, but the fact that
>>> if an exception was raised in the Ada modules, the
>>> exception handler would not work -- the whole unit
>>> would abort.
>> 
>> Lots of things are relevant in exception handling.
>> 
>> First is the exception handling mechanism; set-jump/long-jump vs zero
>> cost. GNAT supports both, with zero cost the default; Windows dlls
>> require sj/lj.
>> 
>> It may be that using a C++ main also implies the sj/lj mechanism.
> 
> Ok, but how is that connected with "-shared"?

Stab in the dark here; I've read in the past when looking for fully 
statically linked programs that shared runtimes are/were needed for c++ 
exception mechanisms to work; or at least to keep all corner cases covered.

So I wouldn't be surprised if -shared did indeed affect some exception 
related stuff.

What I read was something similar to this, but it was a long time ago:

http://www.trilithium.com/johan/2005/06/static-libstdc/