Applied patch #1635: Float patch for inf and nan on Windows (and other platforms).
The patch unifies float("inf") and repr(float("inf")) on all platforms.
diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index a6a29e7..c24b9c5 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -128,7 +128,7 @@
PyObject *
PyFloat_FromString(PyObject *v, char **pend)
{
- const char *s, *last, *end;
+ const char *s, *last, *end, *sp;
double x;
char buffer[256]; /* for errors */
#ifdef Py_USING_UNICODE
@@ -171,6 +171,7 @@
PyErr_SetString(PyExc_ValueError, "empty string for float()");
return NULL;
}
+ sp = s;
/* We don't care about overflow or underflow. If the platform supports
* them, infinities and signed zeroes (on underflow) are fine.
* However, strtod can return 0 for denormalized numbers, where atof
@@ -186,7 +187,26 @@
byte at the end of the string, when the input is inf(inity). */
if (end > last)
end = last;
+ /* Check for inf and nan. This is done late because it rarely happens. */
if (end == s) {
+ char *p = (char*)sp;
+ int sign = 1;
+
+ if (*p == '-') {
+ sign = -1;
+ p++;
+ }
+ if (*p == '+') {
+ p++;
+ }
+ if (PyOS_strnicmp(p, "inf", 4) == 0) {
+ return PyFloat_FromDouble(sign * Py_HUGE_VAL);
+ }
+#ifdef Py_NAN
+ if(PyOS_strnicmp(p, "nan", 4) == 0) {
+ return PyFloat_FromDouble(Py_NAN);
+ }
+#endif
PyOS_snprintf(buffer, sizeof(buffer),
"invalid literal for float(): %.200s", s);
PyErr_SetString(PyExc_ValueError, buffer);
@@ -271,6 +291,8 @@
{
register char *cp;
char format[32];
+ int i;
+
/* Subroutine for float_repr and float_print.
We want float numbers to be recognizable as such,
i.e., they should contain a decimal point or an exponent.
@@ -293,7 +315,33 @@
*cp++ = '.';
*cp++ = '0';
*cp++ = '\0';
+ return;
}
+ /* Checking the next three chars should be more than enough to
+ * detect inf or nan, even on Windows. We check for inf or nan
+ * at last because they are rare cases.
+ */
+ for (i=0; *cp != '\0' && i<3; cp++, i++) {
+ if (isdigit(Py_CHARMASK(*cp)) || *cp == '.')
+ continue;
+ /* found something that is neither a digit nor point
+ * it might be a NaN or INF
+ */
+#ifdef Py_NAN
+ if (Py_IS_NAN(v->ob_fval)) {
+ strcpy(buf, "nan");
+ }
+ else
+#endif
+ if (Py_IS_INFINITY(v->ob_fval)) {
+ cp = buf;
+ if (*cp == '-')
+ cp++;
+ strcpy(cp, "inf");
+ }
+ break;
+ }
+
}
/* XXX PyFloat_AsStringEx should not be a public API function (for one