* bpo-39421: Fix posible crash in heapq with custom comparison operators
* fixup! bpo-39421: Fix posible crash in heapq with custom comparison operators
* fixup! fixup! bpo-39421: Fix posible crash in heapq with custom comparison operators
Replaces the PyList_GET_ITEM and PyList_SET_ITEM macros with normal array
accesses. Replace the siftup unpredicatable branch with arithmetic.
Replace the rc == -1 tests with rc < 0. Gives nicer looking assembly
with both Clang and GCC-4.9. Also gives a small performance both for both.
Clean-up names of static functions.
Use Py_RETURN_NONE macro.
Expose private functions needed to support merge().
Move C imports to the bottom of the Python file.
Consolidates the logic for nlargest() into a single function so that
decoration tuples (elem,order) or (key, order, elem) only need to
be formed when a new element is added to the heap. Formerly, a tuple
was created for every element regardless of whether it was added to
the heap.
The change reduces the number of tuples created, the number of ordering
integers created, and total number of tuple comparisons.
