diff --git a/conts/posix/mm0/mm/task.c b/conts/posix/mm0/mm/task.c
index 2e877f7..df117f0 100644
--- a/conts/posix/mm0/mm/task.c
+++ b/conts/posix/mm0/mm/task.c
@@ -520,18 +520,18 @@ int task_map_stack(struct vm_file *f, struct exec_file_desc *efd,
 		   struct tcb *task, struct args_struct *args,
 		   struct args_struct *env)
 {
-	unsigned long stack_used;
-	unsigned long arg_pages = __pfn(page_align_up(stack_used));
-	char *args_on_stack;
-	void *mapped;
-
 	/*
 	 * Stack contains: args, environment, argc integer,
 	 * 2 Null integers as terminators.
 	 *
 	 * It also needs to be 8-byte aligned.
 	 */
-	stack_used = align_up(args->size + env->size + sizeof(int) * 3 + 8, 8);
+
+	unsigned long stack_used = align_up(args->size + env->size + sizeof(int) * 3 + 8, 8);
+	unsigned long arg_pages = __pfn(page_align_up(stack_used));
+	char *args_on_stack;
+	void *mapped;
+
 	task->stack_end = __pfn_to_addr(cont_mem_regions.task->end);
 	task->stack_start = __pfn_to_addr(cont_mem_regions.task->end) - DEFAULT_STACK_SIZE;
 	task->args_end = task->stack_end;