Upon freeing libxslt's context, every document which is not the *main*
document will be freed by libxslt. If a node of a document which is not
the main document gets returned to userland, we'd free the node twice:
- first by the cleanup of the xslt context
- and then by our own refcounting mechanism.
This was reported in bug 49634, and was fixed by always copying the
node (and later re-fixed in bug 70078).
The original fix is not entirely correct unfortunately because of the
following two main reasons:
- modifications to the node will only modify the copy, and not the original
- accesses to the parent, path, ... will not work
This patch fixes it properly by only copying the node if it origins from
a document other than the main document.
Co-authored-by: juha.ikavalko@agentit.fi
Closes GH-10318.
1925855c0f