[PATCH/RFC] PIC and flat shared library support for m68k

[Richard Sandiford]

David McCullough <david_mccullough at au.securecomputing.com> writes:
> Jivin Richard Sandiford lays it down ...
>> This patch adds m68k support for flat shared libraries and uClinux-style
>> PIC.  The reason I've stuck "RFC" in the subject line is that the shared
>> library side of things is rather different from the uClinux-dist version,
>> and this might make the patch a little controversial.  However, the new
>> approach should still be compatible with the old one, as explained below.
>> 
>> Stepping back a bit, the traditional method for building flat shared
>> libraries does not allow either the libraries or the executable to have
>> constructors and destructors:
>> 
>>   http://www.ucdot.org/article.pl?sid=03/11/25/1126257&mode=thread
>
> Could you run over how the constructots/destructors are broken in the
> current arrangement used by the uClinux-dist.  Myself and a couple
> of others are fairly certain that they were working when we were doing
> m68k on a daily basis.
>
> I won't argue that the uClibc support for flat shared libs needs some
> work though :-)

What link lines do you use?  If you use the ones above, then both
executables and shared libraries are compiled with -nostartfiles,
so you don't get crti.o, crtbegin.o, crtend.o and crtn.o linked in.
That means no _init, _fini, register_frame_info, etc.  If it works
for you, then I imagine you're using something slightly different
to what's given in the uCdot article.  Either that or I'm missing
something ;)

Do you support constructors and destructors in shared libraries as
well as executables?  I couldn't see how that was supposed to work
with the uClinux-dist setup.  Can you also throw exceptions within
shared libraries, and from shared libraries to executables?

Richard