--- ray/src/gen/genbranch.c	1989/09/10 16:45:13	1.2
+++ ray/src/gen/genbranch.c	1993/06/04 14:30:48	2.3
@@ -12,6 +12,8 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  <stdio.h>
 
+#include  <math.h>
+
 #include  "random.h"
 
 #define  errf()		(var*(0.5-frandom()))
@@ -35,7 +37,6 @@ main(argc, argv)
 int  argc;
 char  *argv[];
 {
-	double  atof();
 	int  i, j;
 
 	for (i = 1; i < argc && argv[i][0] == '-'; i++)