pgsql: Patch some corner-case bugs in pl/python.

Patch some corner-case bugs in pl/python.

Dave Malcolm of Red Hat is working on a static code analysis tool for
Python-related C code. It reported a number of problems in plpython,
most of which were failures to check for NULL results from object-creation
functions, so would only be an issue in very-low-memory situations.

Patch in HEAD and 9.1. We could go further back but it's not clear that
these issues are important enough to justify the work.

Jan Urbański

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/5cd72c7a7c7bd76ab028e1dc59d90a47750acebe

Modified Files
--------------
src/pl/plpython/plpy_elog.c | 4 ++++
src/pl/plpython/plpy_main.c | 2 ++
src/pl/plpython/plpy_plpymodule.c | 18 ++++++++++++++++--
src/pl/plpython/plpy_spi.c | 3 ++-
src/pl/plpython/plpy_typeio.c | 2 ++
5 files changed, 26 insertions(+), 3 deletions(-)