SF bug 115831 and Ping's SF patch 101751, 0.0**-2.0 returns inf rather than
raise ValueError. Checked in the patch as far as it went, but also changed
all of ints, longs and floats to raise ZeroDivisionError instead when raising
0 to a negative number. This is what 754-inspired stds require, as the "true
result" is an infinity obtained from finite operands, i.e. it's a singularity.
Also changed float pow to not be so timid about using its square-and-multiply
algorithm. Note that what math.pow does is unrelated to what builtin pow
does, and will still vary by platform.
diff --git a/Objects/longobject.c b/Objects/longobject.c
index 65dcaa0..bfb431f 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -1244,8 +1244,12 @@
size_b = b->ob_size;
if (size_b < 0) {
- PyErr_SetString(PyExc_ValueError,
- "long integer to the negative power");
+ if (a->ob_size)
+ PyErr_SetString(PyExc_ValueError,
+ "long integer to a negative power");
+ else
+ PyErr_SetString(PyExc_ZeroDivisionError,
+ "zero to a negative power");
return NULL;
}
z = (PyLongObject *)PyLong_FromLong(1L);