1 files changed, 17 insertions, 0 deletions
diff --git a/ruby_1_8_5/missing/isnan.c b/ruby_1_8_5/missing/isnan.c
new file mode 100644
index 0000000000..459048e936
--- /dev/null
+++ b/ruby_1_8_5/missing/isnan.c
@@ -0,0 +1,17 @@
+/* public domain rewrite of isnan(3) */
+
+static int double_ne();
+
+int
+isnan(n)
+    double n;
+{
+    return double_ne(n, n);
+}
+
+static int
+double_ne(n1, n2)
+    double n1, n2;
+{
+    return n1 != n2;
+}