diff --git a/libm/src/s_logb.c b/libm/src/s_logb.c
index 30edb8749..57f91c44d 100644
--- a/libm/src/s_logb.c
+++ b/libm/src/s_logb.c
@@ -36,9 +36,9 @@ logb(double x)
 	if(ix>=0x7ff00000) return x*x;
 	if(ix<0x00100000) {
 		x *= two54;		 /* convert subnormal x to normal */
-		GET_FLOAT_WORD(ix,x);
+		GET_HIGH_WORD(ix,x);
 		ix &= 0x7fffffff;
-		return (float) ((ix>>20)-1023-54);
+		return (double) ((ix>>20)-1023-54);
 	} else
 		return (double) ((ix>>20)-1023);
 }