diff --git a/src/eval.c b/src/eval.c
index 018956135..30acedd9e 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1027,7 +1027,7 @@ int ldbDelBreakpoint(int line) {
     for (j = 0; j < ldb.bpcount; j++) {
         if (ldb.bp[j] == line) {
             ldb.bpcount--;
-            memmove(ldb.bp+j,ldb.bp+j+1,ldb.bpcount-j);
+            memmove(ldb.bp+j,ldb.bp+j+1,(ldb.bpcount-j) * sizeof(int));
             return 1;
         }
     }