Fix double free

lisp/kernel.gl

@@ -1,4 +1,4 @@
 ;; -*- mode: lisp-data -*-
 
 (print (funcall (let ((te 'a))
-                    (lambda (b &optional (a te)) a)) 2))
+                    (lambda (b &optional (a te ap)) a)) 2 3))

src/stack.c

@@ -193,7 +193,8 @@ void compact_stack_frame(struct StackFrame *restrict frame) {
     for (size_t i = 1; i < refs->num_blocks; ++i) {
         lisp_free(refs->blocks[i]);
     }
-    lisp_realloc(refs->blocks, sizeof(struct LocalReferencesBlock *));
+    refs->blocks =
+        lisp_realloc(refs->blocks, sizeof(struct LocalReferencesBlock *));
     refs->num_blocks = 1;
 }