From: Guido van Rossum <guido@python.org>
Date: Tue, 28 May 1991 21:57:39 +0000 (+0000)
Subject: Fix special cases in pow()
X-Git-Tag: v0.9.8~934
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=70d934601f743afe0f9a75fef95d6c3e65ec9bfd;p=thirdparty%2FPython%2Fcpython.git

Fix special cases in pow()
---

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index 0549990a1b16..e2095d723cb2 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -223,8 +223,20 @@ float_pow(v, w)
 	}
 	iv = v->ob_fval;
 	iw = ((floatobject *)w)->ob_fval;
+	/* Sort out special cases here instead of relying on pow() */
 	if (iw == 0.0)
 		return newfloatobject(1.0); /* x**0 is 1, even 0**0 */
+	if (iv == 0.0) {
+		if (iw < 0.0) {
+			err_setstr(RuntimeError, "0.0 to the negative power");
+			return NULL;
+		}
+		return newfloatobject(0.0);
+	}
+	if (iv < 0.0) {
+		err_setstr(RuntimeError, "negative float to float power");
+		return NULL;
+	}
 	errno = 0;
 	ix = pow(iv, iw);
 	if (errno != 0) {