new_arena():  In error cases, reset the number of available pools to 0.
Else the pymalloc malloc will go insane the next time it's called.
diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c
index c766ccd..23bf0a9 100644
--- a/Objects/obmalloc.c
+++ b/Objects/obmalloc.c
@@ -424,6 +424,7 @@
 
 error:
 	PyMem_FREE(bp);
+	nfreepools = 0;
 	return NULL;
 }