SF patch 514641 (Naofumi Honda) - Negative ob_size of LongObjects
Due to the bizarre definition of _PyLong_Copy(), creating an instance
of a subclass of long with a negative value could cause core dumps
later on. Unfortunately it looks like the behavior of _PyLong_Copy()
is quite intentional, so the fix is more work than feels comfortable.
This fix is almost, but not quite, the code that Naofumi Honda added;
in addition, I added a test case.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index dd95dde..e667efb 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -1748,6 +1748,10 @@
verify((a + 0).__class__ is long)
verify((0 + a).__class__ is long)
+ # Check that negative clones don't segfault
+ a = longclone(-1)
+ vereq(a.__dict__, {})
+
class precfloat(float):
__slots__ = ['prec']
def __init__(self, value=0.0, prec=12):