Issue #2801: fix bug in float.is_integer where ValueError

mark.dickinson · mark.dickinson · commit 28b94b413dac · 2008-05-09T16:14:15.000Z
could be incorrectly raised. This is a backport of the Py3k fix in r62939. (Should really have been fixed in the trunk first and svnmerged into py3k.) git-svn-id: http://svn.python.org/projects/python/trunk@62943 6015fed2-1504-0410-9fe1-9d1591cc4771
diff --git a/Misc/NEWS b/Misc/NEWS
@@ -12,6 +12,9 @@ What's New in Python 2.6 beta 1?
 Core and Builtins
 -----------------
 
+- Issue #2801: fix bug in the float.is_integer method where a ValueError
+  was sometimes incorrectly raised.
+
 - Issue #2790: sys.flags was not properly exposing its bytes_warning attribute.
 
 Extension Modules
diff --git a/Objects/floatobject.c b/Objects/floatobject.c
@@ -1031,6 +1031,7 @@ float_is_integer(PyObject *v)
 		return NULL;
 	if (!Py_IS_FINITE(x))
 		Py_RETURN_FALSE;
+	errno = 0;
 	PyFPE_START_PROTECT("is_integer", return NULL)
 	o = (floor(x) == x) ? Py_True : Py_False;
 	PyFPE_END_PROTECT(x)
