diff --git a/samples/strcat.noja b/samples/strcat.noja
index a875948..657411d 100644
--- a/samples/strcat.noja
+++ b/samples/strcat.noja
@@ -11,7 +11,7 @@ fun append_esclamation_mark(A, n)
 	
 	i = 0;
 	while i < n:
-		{
+		{	
 			A = strcat(A, '!');
 			i = i + 1;
 		}
@@ -19,4 +19,4 @@ fun append_esclamation_mark(A, n)
 	return A;
 }
 
-print(append_esclamation_mark(D, 7), '\n');
\ No newline at end of file
+print(append_esclamation_mark(D, 3), '\n');
\ No newline at end of file
diff --git a/src/runtime/o_closure.c b/src/runtime/o_closure.c
index 71c1394..737fa4f 100644
--- a/src/runtime/o_closure.c
+++ b/src/runtime/o_closure.c
@@ -1,3 +1,6 @@
+// NOTE: This data structure doesn't strictly depend on
+//       the runtime, so it could be moved to src/objects.
+
 #include "../utils/defs.h"
 #include "../objects/objects.h"
 
diff --git a/src/runtime/o_nfunc.c b/src/runtime/o_nfunc.c
index cfad689..ba61964 100644
--- a/src/runtime/o_nfunc.c
+++ b/src/runtime/o_nfunc.c
@@ -73,7 +73,10 @@ static Object *call(Object *self, Object **argv, unsigned int argc, Heap *heap,
 					argv2[i] = Object_NewNone(heap, error);
 
 					if(argv2[i] == NULL)
-						return 0;
+						{
+							free(argv2);
+							return NULL;
+						}
 				}
 		}
 	else UNREACHABLE;