[Python-checkins] cpython: Return +-Py_HUGE_VAL for tgamma(+-0) instead of risking FP exceptions by

[mark.dickinson]

http://hg.python.org/cpython/rev/7482d0e3476a
changeset:   72467:7482d0e3476a
user:        Mark Dickinson <mdickinson at enthought.com>
date:        Sun Sep 25 15:26:43 2011 +0100
summary:
  Return +-Py_HUGE_VAL for tgamma(+-0) instead of risking FP exceptions by computing 1.0 / 0.0.

files:
  Modules/mathmodule.c |  3 ++-
  1 files changed, 2 insertions(+), 1 deletions(-)


diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
--- a/Modules/mathmodule.c
+++ b/Modules/mathmodule.c
@@ -239,7 +239,8 @@
     }
     if (x == 0.0) {
         errno = EDOM;
-        return 1.0/x; /* tgamma(+-0.0) = +-inf, divide-by-zero */
+        /* tgamma(+-0.0) = +-inf, divide-by-zero */
+        return copysign(Py_HUGE_VAL, x);
     }
 
     /* integer arguments */

-- 
Repository URL: http://hg.python.org/cpython