Memory leak in Python query constructor

[richard]

The python query constructor which takes a sequence of queries as an argument leaks memory, due to failing to decref python objects returned from PySequence?_GetItem. I think there are also other memory leaks in the related code. I have a small testcase which reproduces this; though not to hand at present. Making this issue as a placeholder to keep track of this issue.

(Note that valgrind doesn't seem to be able to detect the leak, but the testcase I have is very simple and clear and rapidly uses up 100s of Mbs of memory.)

[richard]

Simple test case which demonstrates the leak (if watched in top)

[richard]

Fixed in HEAD in revision [11158]

[olly]

Fixed in 1.0 branch rev [11171]