[Python-checkins] cpython: Issue #22117: Try to fix rounding in conversion from Python double to _PyTime_t

Mon Mar 30 10:22:23 CEST 2015

https://hg.python.org/cpython/rev/e00b581a65ec
changeset: 95286:e00b581a65ec
user: Victor Stinner <victor.stinner at gmail.com>
date: Mon Mar 30 10:22:16 2015 +0200
summary:
 Issue #22117: Try to fix rounding in conversion from Python double to _PyTime_t
using the C volatile keyword.
files:
 Python/pytime.c | 3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/Python/pytime.c b/Python/pytime.c
--- a/Python/pytime.c
+++ b/Python/pytime.c
@@ -207,7 +207,8 @@
 _PyTime_FromSecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
 {
 if (PyFloat_Check(obj)) {
- double d, err;
+ /* volatile avoids unsafe optimization on float enabled by gcc -O3 */
+ volatile double d, err;
 
 /* convert to a number of nanoseconds */
 d = PyFloat_AsDouble(obj);
-- 
Repository URL: https://hg.python.org/cpython
