--- ray/src/gen/genrev.c	1991/04/23 15:51:17	1.9
+++ ray/src/gen/genrev.c	1992/10/02 16:11:28	2.2
@@ -15,9 +15,10 @@ static char SCCSid[] = "$SunId$ LBL";
  */
 
 #include  <stdio.h>
+#include  <math.h>
 
-#define  ZNAME		"Z_"			/* z function name */
-#define  RNAME		"R_"			/* r function name */
+#define  ZNAME		"Z`SYS`"		/* z function name */
+#define  RNAME		"R`SYS`"		/* r function name */
 
 #define  PI		3.14159265358979323846
 
@@ -160,7 +161,6 @@ userror:
 computen(nzp, nrp, z0, r0, z1, r1)		/* compute normal */
 double  *nzp, *nrp, z0, r0, z1, r1;
 {
-	extern double  sqrt();
 	double  dr, dz, len;
 
 	dz = r0 - r1;				/* right angle vector */