Re: [Tinycc-devel] [PATCH] TCC arm64 back end

[Michael Matz]

Hi,

On Mon, 13 Apr 2015, Thomas Preud'homme wrote:

> > exporting _all_ global symbols from an executable always, only symbols
> > actually undefined in shared libs and provided by the executable are
> > exported (included as defined in .dynsym).  That's the purpose of
> > bind_libs_dynsyms.
> 
> It doesn't have to be undefined. I just did a test with ld and it 
> exports symbol form the program if it's present in a dynsym of any 
> library.

Ah right, that's actually what makes more sense than just doing it for 
undef symbols.

> > > That should only be necessary for tcc_run but that require changing
> > > bind_libs_dynsyms (which requires changing anyway because of the bug
> > > above).
> > 
> > I don't see that.  Also undefined references from shared libs should only
> > be satisfied by the executable if they are mentioned directly on the
> > command line I think.
> 
> Nope. Try it for yourself:

Huh, indeed.  IMHO that's inconsistent with the symbol resolution 
behaviour of GNU ld (only looking in level0 libs for symbols, not in those 
DT_NEEDED by them, unless --copy-dt-needed-entries is active), but so be 
it.

> Thanks for teaching me, I really appreciate. It seems that despite what 
> you told, you understand tcc's linker at least as well as me. Anyway, if 
> you don't mind I'd still like to be the one to improve its organisation. 
> I'll appreciate any review of my changes though.

Sure, no problem.


Ciao,
Michael.