[Xcb] xcb/libxcb git commit 46413cd85

Josh Triplett josh at freedesktop.org
Fri Dec 14 15:03:55 PST 2007

Barton C Massey wrote:
> > In message <475ED27B.7000701 at hummingbird.com> you wrote:
>> >> Eamon Walsh wrote:
>>> >>> +        <doc> * The returned value must be freed by the caller using free().</doc>
>> >> That should read xcb_free(), not free().
>> >>
>> >> Oh. I see we don't have an xcb_free() function. That can be considered a
>> >> bug. Some systems (*cough* Windows *cough*) frequently run into problems
>> >> when a shared library is linked to a different libc (and therefore a
>> >> different malloc/realloc/free) than the executable.
>> >>
>> >> Xlib has XFree(). XCB needs its own free() for all the same reasons.
>> >>
>> >> If you like, I can create a patch to add this function.
> > 
> > While I understand what you're saying, I have to
> > respectfully disagree here.  Unlike with Xlib, we worked
> > hard in the API design of XCB to ensure that it always uses
> > system malloc(), and therefore can always use system free().
> > If someone's boxes are sufficiently borked that they can't
> > call free() on pointers created by malloc() calls in their
> > library, in my opinion we can't let this be XCB's problem.
> > 
> > Splitting the interface imposes an extra software
> > engineering burden of making sure that some distant routine
> > knows whether the data structure it is freeing came from XCB
> > or elsewhere---I am loathe to impose this burden, especially
> > since bugs of this type will rarely be exercised and
> > therefore casual mistakes will be made and propagated.  In
> > addition, splitting the interface encourages the design of
> > magic memory allocators and deallocators for XCB, which I am
> > also happy to discourage.

This perfectly describes my opinion on xcb_free as well.

- Josh Triplett

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 252 bytes
Desc: OpenPGP digital signature
Url : http://lists.freedesktop.org/archives/xcb/attachments/20071214/03f945bf/attachment.pgp 

More information about the Xcb mailing list