--- ray/src/rt/source.c	1990/03/27 11:40:13	1.21
+++ ray/src/rt/source.c	1990/11/13 14:32:30	1.22
@@ -310,6 +310,8 @@ char  *p;			/* data for f */
 	double  prob, ourthresh, hwt, test2, hit2;
 	RAY  sr;
 
+	if (nsources <= 0)
+		return;
 	srccnt = (CONTRIB *)malloc(nsources*sizeof(CONTRIB));
 	cntord = (CNTPTR *)malloc(nsources*sizeof(CNTPTR));
 	if (srccnt == NULL || cntord == NULL)