[cwittich] 39586: work around missing fpclassify

Author: cwittich
Date: Fri Feb 13 11:55:03 2009
New Revision: 39586

URL: http://svn.reactos.org/svn/reactos?rev=39586&view=rev
Log:
work around missing fpclassify

Modified:
    trunk/reactos/include/crt/math.h

Modified: trunk/reactos/include/crt/math.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/include/crt/math.h?rev=395…
==============================================================================
--- trunk/reactos/include/crt/math.h [iso-8859-1] (original)
+++ trunk/reactos/include/crt/math.h [iso-8859-1] Fri Feb 13 11:55:03 2009
@@ -279,7 +279,24 @@
 #define isfinite(x) ((fpclassify(x) & FP_NAN) == 0)
 
   /* 7.12.3.3 */
-#define isinf(x) (fpclassify(x) == FP_INFINITE)
+/* #define isinf(x) (fpclassify(x) == FP_INFINITE) */
+
+  /* we don't have fpclassify */
+static int isinf (double d) {
+  int expon = 0;
+  double val = frexp (d, &expon);
+  if (expon == 1025) {
+    if (val == 0.5) {
+        return 1;
+    } else if (val == -0.5) {
+        return -1;
+    } else {
+        return 0;
+    }
+  } else {
+    return 0;
+  }
+}
 
   /* 7.12.3.4 */
   /* We don't need to worry about trucation here: