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SF bug #444510: int() should guarantee truncation.

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It's guaranteed now, assuming the platform modf() works correctly.
This commit is contained in:
Tim Peters 2001-07-26 20:02:17 +00:00
parent 7cf92fa1c8
commit 7321ec437b
3 changed files with 27 additions and 10 deletions
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20
Objects/floatobject.c
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@ -606,13 +606,19 @@ static PyObject *
float_int(PyObject *v)
{
double x = PyFloat_AsDouble(v);
if (x < 0 ? (x = ceil(x)) < (double)LONG_MIN
: (x = floor(x)) > (double)LONG_MAX) {
PyErr_SetString(PyExc_OverflowError,
"float too large to convert");
return NULL;
}
return PyInt_FromLong((long)x);
double wholepart; /* integral portion of x, rounded toward 0 */
long aslong; /* (long)wholepart */
(void)modf(x, &wholepart);
/* doubles may have more bits than longs, or vice versa; and casting
to long may yield gibberish in either case. What really matters
is whether converting back to double again reproduces what we
started with. */
aslong = (long)wholepart;
if ((double)aslong == wholepart)
return PyInt_FromLong(aslong);
PyErr_SetString(PyExc_OverflowError, "float too large to convert");
return NULL;
}
static PyObject *