From 8d886db1db1d44cda07f07346d67b3defb5b5a83 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Wed, 12 Apr 2017 13:09:21 +0900
Subject: [PATCH] avoid variable-length field

---
 lib/gc.c     | 5 ++++-
 lib/object.h | 2 +-
 lib/proc.c   | 6 ++++--
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/gc.c b/lib/gc.c
index 133646c8..e36b9834 100644
--- a/lib/gc.c
+++ b/lib/gc.c
@@ -422,9 +422,12 @@ gc_finalize_object(pic_state *pic, struct object *obj)
     pic_fclose(pic, obj_value(pic, obj)); /* FIXME */
     break;
   }
+  case PIC_TYPE_FRAME: {
+    pic_free(pic, obj->u.frame.storage);
+    break;
+  }
 
   case PIC_TYPE_PAIR:
-  case PIC_TYPE_FRAME:
   case PIC_TYPE_ERROR:
   case PIC_TYPE_RECORD:
   case PIC_TYPE_PROC_FUNC:
diff --git a/lib/object.h b/lib/object.h
index 9f152a49..2aae3d00 100644
--- a/lib/object.h
+++ b/lib/object.h
@@ -95,7 +95,7 @@ struct frame {
   int regc;
   pic_value *regs;
   struct frame *up;
-  pic_value storage[1];
+  pic_value *storage;
 };
 
 struct proc {
diff --git a/lib/proc.c b/lib/proc.c
index 5d4e2467..8751c8a9 100644
--- a/lib/proc.c
+++ b/lib/proc.c
@@ -39,7 +39,8 @@ pic_make_proc_func(pic_state *pic, pic_func_t func, int n, pic_value *env)
 
   if (n > 0) {
     int i;
-    fp = (struct frame *)pic_obj_alloc(pic, offsetof(struct frame, storage) + sizeof(pic_value) * n, PIC_TYPE_FRAME);
+    fp = (struct frame *)pic_obj_alloc(pic, sizeof(struct frame), PIC_TYPE_FRAME);
+    fp->storage = pic_malloc(pic, sizeof(pic_value) * n);
     fp->regc = n;
     fp->regs = fp->storage;
     fp->up = NULL;
@@ -350,7 +351,8 @@ vm_push_cxt(pic_state *pic)
 {
   struct callinfo *ci = pic->ci;
 
-  ci->cxt = (struct frame *)pic_obj_alloc(pic, offsetof(struct frame, storage) + sizeof(pic_value) * ci->regc, PIC_TYPE_FRAME);
+  ci->cxt = (struct frame *)pic_obj_alloc(pic, sizeof(struct frame), PIC_TYPE_FRAME);
+  ci->cxt->storage = pic_malloc(pic, sizeof(pic_value) * ci->regc);
   ci->cxt->up = ci->up;
   ci->cxt->regc = ci->regc;
   ci->cxt->regs = ci->regs;