If awailable, enable -fstrict-overflow for libmpdec. Also
shut off false positive warnings (-Warray-bounds).
The later was backported from mpdecimal-4.0.0.
Allow controlling Expat >=2.6.0 reparse deferral (CVE-2023-52425) by adding five new methods:
- `xml.etree.ElementTree.XMLParser.flush`
- `xml.etree.ElementTree.XMLPullParser.flush`
- `xml.parsers.expat.xmlparser.GetReparseDeferralEnabled`
- `xml.parsers.expat.xmlparser.SetReparseDeferralEnabled`
- `xml.sax.expatreader.ExpatParser.flush`
Based on the "flush" idea from https://github.com/python/cpython/pull/115138#issuecomment-1932444270 .
### Notes
- Please treat as a security fix related to CVE-2023-52425.
Includes code suggested-by: Snild Dolkow <snild@sony.com>
and by core dev Serhiy Storchaka.
Seth Michael Larson
Jonathan Protzenko
Yuriy Chernyshov
Sergey B Kirpichev
Sebastian Pipping
Stéphane Bidoul
Seth Michael Larson