Re: [xml] Curious Segmentation Fault

[Daniel Veillard <veillard redhat com>]

On Mon, Apr 05, 2004 at 11:45:39AM -0400, Anthony Carrico wrote:
> On Mon, Apr 05, 2004 at 03:14:54AM -0400, Daniel Veillard wrote:
> > On Sun, Apr 04, 2004 at 11:33:05PM -0400, Anthony Carrico wrote:
> > > Why?
> >
> >   Because after element.unlinkNode(), the element still references
> > the document, and element.unlinkNode() checks it to find if the
> > strings from the element came from the document dictionary.
> > If you free the document after any element which references it you
> > don't have the problem. Allocation granularity in libxml2 is
> > at the document level.
>
> So the third example (which seems to succed) is also illegal. Correct?
> This one:
>
> > > import libxml2
> > > libxml2.debugMemory(1)
> > > doc = libxml2.newDoc("1.0")
> > > element = doc.newChild(None, "test", None)
> > > element.unlinkNode()
> > > doc.freeDoc()

  you free doc, element is linked to doc, you freed element underlying
data there.

> > > doc = libxml2.newDoc("1.0")
> > > doc.addChild(element)
> > > element.unlinkNode()

  that should crash,  element underlying node has been freed.

Again, the main unit of memory allocation in libxml2 is the document.

Daniel

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