Fix concat_ws() to not insert a separator after leading NULL argument(s).
Per bug #6181 from Itagaki Takahiro. Also do some marginal code cleanup
and improve error handling.
Branch
------
REL9_1_STABLE
Details
-------
http://git.postgresql.org/pg/commitdiff/579577320ef449442f804043a67ce5c13d679679
Modified Files
--------------
src/backend/utils/adt/varlena.c | 34 +++++++++++++++++++++++-----------
1 files changed, 23 insertions(+), 11 deletions(-)