Re: [Devel] broken binary compatibility

[Owen Taylor]

"Pavel Kankovsky" <address@hidden> writes:

> On 29 Jun 2002, Arkadiusz Miskiewicz wrote:
> 
> >  2002-02-24  David Turner  <address@hidden>
> >        * Renaming stream functions to the FT_<Subject>_<Action> scheme:     
> >   
> > 
> >  That is very, very bad thing because SO name of library was not changed
> >  while that renaming thing broke binary compatibility of library.
> 
> I do not see how those changes affected the binary interface. As far
> as I know the functions whose names changed are *private* functions
> that are *not* a part of FT2 public interface. Like everything else
> in include/freetype/internal/*.h.

Probably the reason that the problem is being noticed is Pango;
Pango uses these functions because it contains a large chunk
of code lifted from FreeType1; it would be cleaner (if not
more efficient) to simply get the tables as a single chunk
and parse them with Pango-specific code rather than of using 
the stream interfaces.

But I've never had the time to implement this.

The real problem here is that there is no way to express 
multiple sets of interfaces exported by a single library
with the Unix soname scheme.

It would be nice to encode the information:

  Pango depends on freetype.so.6, and freetype-internals version 
  version 532.

[ It may well be possible to encode something like this
  with symbol versioning; but symbol versioning isn't 
  very portable ]

Regards,
                                        Owen