1 files changed, 3 insertions, 2 deletions

diff --git a/src/lj_obj.h b/src/lj_obj.h
index f243a75b..a6637954 100644
--- a/src/lj_obj.h
+++ b/src/lj_obj.h
@@ -429,7 +429,7 @@ typedef struct GCfuncC {
 
 typedef struct GCfuncL {
   GCfuncHeader;
-  GCRef pt;             /* Link to prototype this function is based on. */
+  MRef pc;              /* Start PC (and GCproto reference). */
   GCRef uvptr[1];       /* Array of _pointers_ to upvalue objects (GCupval). */
 } GCfuncL;
 
@@ -443,7 +443,8 @@ typedef union GCfunc {
 #define isluafunc(fn)   ((fn)->c.ffid == FF_LUA)
 #define iscfunc(fn)     ((fn)->c.ffid == FF_C)
 #define isffunc(fn)     ((fn)->c.ffid > FF_C)
-#define funcproto(fn)   check_exp(isluafunc(fn), &gcref((fn)->l.pt)->pt)
+#define funcproto(fn) \
+  check_exp(isluafunc(fn), (GCproto *)(mref((fn)->l.pc, char)-sizeof(GCproto)))
 #define sizeCfunc(n)    (sizeof(GCfuncC)-sizeof(TValue)+sizeof(TValue)*(n))
 #define sizeLfunc(n)    (sizeof(GCfuncL)-sizeof(GCRef)+sizeof(GCRef)*(n))