2.5-18.1

1 files changed, 32 insertions, 0 deletions

diff --git a/math/w_log2.c b/math/w_log2.c
new file mode 100644
index 0000000000..d56a6ee663
--- /dev/null
+++ b/math/w_log2.c
@@ -0,0 +1,32 @@
+/*
+ * wrapper log2(X)
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+double
+__log2 (double x)	/* wrapper log2 */
+{
+#ifdef _IEEE_LIBM
+  return __ieee754_log2 (x);
+#else
+  double z;
+  z = __ieee754_log2 (x);
+  if (_LIB_VERSION == _IEEE_ || __isnan (x)) return z;
+  if (x <= 0.0)
+    {
+      if (x == 0.0)
+	return __kernel_standard (x, x, 48); /* log2 (0) */
+      else
+	return __kernel_standard (x, x, 49); /* log2 (x < 0) */
+    }
+  else
+    return z;
+#endif
+}
+weak_alias (__log2, log2)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__log2, __log2l)
+weak_alias (__log2, log2l)
+#endif