Re: Why kdelibs4-dev and XFree86 4.3.0 don't play nice together (was: Re: xlibs-pic)
On Wed, 2003-06-04 at 01:51, John Gay wrote:
> >> This was my understanding as well. As I understand the situation, -fPIC
> >> preferable to the non-PIC code which was there before.
> >It's not quite that simple. This is about static libraries, which policy
> >requires to be built without -fPIC. The problem arises when linking them
> >into shared objects, for which there's xlibs-pic, like other -pic
> Ah! I see, Ted. (Do you really, Dougal? Uhm, No, not really.)
> Can you tell that I only know about PIC from a course in O/S's? I'd be
> really interested in a proper explaination for this.
> I know that PIC code is 'supposed' to be better in that it can be loaded
> into memory without regard to the actual location or layout. Why should
> static libraries be built without -fPIC, and who's policy is it anyway?
Debian's. I guess the reason is that PIC code usually performs worse
than non-PIC code (at least on weird architectures like i386) and that
static libraries are usually linked directly into applications.
> And why are static lib's being linked into shared objects?
Because some shared libraries (or plugins, or whatever) use some X
extension libraries which are only available in static form. But non-PIC
code in a shared object is a bad idea, it (like so many things...) only
works on i386 (and maybe some other architectures) by coincidence. On
other architectures, this causes build or run time errors.
Earthling Michel Dänzer \ Debian (powerpc), XFree86 and DRI developer
Software libre enthusiast \ http://svcs.affero.net/rm.php?r=daenzer