Merged revisions 67707 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r67707 | mark.dickinson | 2008-12-11 19:28:08 +0000 (Thu, 11 Dec 2008) | 5 lines

  Issues #3167, #3682: tests for math.log and math.log10 were failing on
  Solaris and OpenBSD.  Fix this by handling special values and domain
  errors directly in mathmodule.c, passing only positive nonspecial floats
  to the system log/log10.
........

diff --git a/Misc/NEWS b/Misc/NEWS
index 5f3347910e7b24bc2177b345d955c0328bb2c657..10a074599066af2d0b2f13d783c02cc4177f483a 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -87,6 +87,11 @@ Library
   support unusual filenames (such as those containing semi-colons) in
   Content-Disposition headers.
 
+Extension Modules
+-----------------
+
+- Issues #3167, #3682: Fix test_math failures for log, log10 on Solaris,
+  OpenBSD.
 
 Build
 -----

diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
index d23d2ffcb5df59ceb79f1ac3e180bbcb357f2cf2..1eb0c2be72073ae8754c715a8319f3aeb83ae114 100644 (file)
--- a/Modules/mathmodule.c
+++ b/Modules/mathmodule.c
@@ -136,6 +136,58 @@ m_atan2(double y, double x)
        return atan2(y, x);
 }
 
+/*
+    Various platforms (Solaris, OpenBSD) do nonstandard things for log(0),
+    log(-ve), log(NaN).  Here are wrappers for log and log10 that deal with
+    special values directly, passing positive non-special values through to
+    the system log/log10.
+ */
+
+static double
+m_log(double x)
+{
+       if (Py_IS_FINITE(x)) {
+               if (x > 0.0)
+                       return log(x);
+               errno = EDOM;
+               if (x == 0.0)
+                       return -Py_HUGE_VAL; /* log(0) = -inf */
+               else
+                       return Py_NAN; /* log(-ve) = nan */
+       }
+       else if (Py_IS_NAN(x))
+               return x; /* log(nan) = nan */
+       else if (x > 0.0)
+               return x; /* log(inf) = inf */
+       else {
+               errno = EDOM;
+               return Py_NAN; /* log(-inf) = nan */
+       }
+}
+
+static double
+m_log10(double x)
+{
+       if (Py_IS_FINITE(x)) {
+               if (x > 0.0)
+                       return log10(x);
+               errno = EDOM;
+               if (x == 0.0)
+                       return -Py_HUGE_VAL; /* log10(0) = -inf */
+               else
+                       return Py_NAN; /* log10(-ve) = nan */
+       }
+       else if (Py_IS_NAN(x))
+               return x; /* log10(nan) = nan */
+       else if (x > 0.0)
+               return x; /* log10(inf) = inf */
+       else {
+               errno = EDOM;
+               return Py_NAN; /* log10(-inf) = nan */
+       }
+}
+
+
 /*
    math_1 is used to wrap a libm function f that takes a double
    arguments and returns a double.
@@ -831,11 +883,11 @@ math_log(PyObject *self, PyObject *args)
        if (!PyArg_UnpackTuple(args, "log", 1, 2, &arg, &base))
                return NULL;
 
-       num = loghelper(arg, log, "log");
+       num = loghelper(arg, m_log, "log");
        if (num == NULL || base == NULL)
                return num;
 
-       den = loghelper(base, log, "log");
+       den = loghelper(base, m_log, "log");
        if (den == NULL) {
                Py_DECREF(num);
                return NULL;
@@ -854,7 +906,7 @@ If the base not specified, returns the natural logarithm (base e) of x.");
 static PyObject *
 math_log10(PyObject *self, PyObject *arg)
 {
-       return loghelper(arg, log10, "log10");
+       return loghelper(arg, m_log10, "log10");
 }
 
 PyDoc_STRVAR(math_log10_doc,