Defend against null error message reported by libxml2.
While this isn't really supposed to happen, it can occur in OOM
situations and perhaps others. Instead of crashing, substitute
"(no message provided)".
I didn't worry about localizing this text, since we aren't
localizing anything else here; besides, if we're on the edge of
OOM, it's unlikely gettext() would work.
Report and fix by Sergio Conde Gómez in bug #15624.
Discussion: https://postgr.es/m/15624-4dea54091a2864e6@postgresql.org
Branch
------
REL9_6_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/ef922faea703aff4996eab17520cb5201a793701
Modified Files
--------------
src/backend/utils/adt/xml.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
