diff --git a/src/triangulate.c b/src/triangulate.c
index 9d4b2a881766891a956e4e9056633674c43a311a..2d6c83155fb6c4c2ff8b556db96aec023820d2a8 100755
--- a/src/triangulate.c
+++ b/src/triangulate.c
@@ -816,7 +816,7 @@ int generate_random_ordering(int n) {
 
 /* Return the next segment in the generated random ordering of all the */
 /* segments in S */
-int choose_segment() {
+int choose_segment(void) {
 #ifdef DEBUG
   Rprintf("choose_segment: %d\n", permute[choose_idx]);
 #endif