+#elif HAVE_LOG10L
+
+# include <float.h>
+
+long double
+log10l (long double x)
+# undef log10l
+{
+ /* Work around the OSF/1 5.1 bug. */
+ if (x == 0.0L)
+ /* Return -Infinity. */
+ return -1.0L / 0.0L;
+ {
+ long double y = log10l (x);
+# ifdef __sgi
+ /* Normalize the +Infinity value. */
+ if (y > LDBL_MAX)
+ y = 1.0L / 0.0L;
+# endif
+ return y;
+ }
+}
+