diff --git a/src/lj_bcread.c b/src/lj_bcread.c
index 52a22da9ed..2d84c46736 100644
--- a/src/lj_bcread.c
+++ b/src/lj_bcread.c
@@ -152,7 +152,7 @@ static uint32_t bcread_uleb128_33(LexState *ls)
 static void bcread_dbg(LexState *ls, GCproto *pt, MSize sizedbg)
 {
   uint32_t *lineinfo = (uint32_t*)proto_lineinfo(pt);
-  bcread_block(ls, (void*)proto_declname(pt), sizedbg);
+  bcread_block(ls, (void*)lineinfo, sizedbg);
   /* Swap lineinfo if the endianess differs. */
   if (bcread_swap(ls)) {
     int i;
@@ -298,9 +298,9 @@ GCproto *lj_bcread_proto(LexState *ls)
 {
   GCproto *pt;
   MSize framesize, numparams, flags, sizeuv, sizekgc, sizekn, sizebc, sizept;
-  MSize ofsk, ofsuv, ofsdbg;
+  MSize ofsk, ofsuv, ofsdbg, ofsdeclname = 0;
   MSize sizedbg = 0;
-  BCLine firstline = 0, numline = 0, ndeclname = 0;
+  BCLine firstline = 0, numline = 0;
 
   /* Read prototype header. */
   flags = bcread_byte(ls);
@@ -313,9 +313,9 @@ GCproto *lj_bcread_proto(LexState *ls)
   if (!(bcread_flags(ls) & BCDUMP_F_STRIP)) {
     sizedbg = bcread_uleb128(ls);
     if (sizedbg) {
-      ndeclname = bcread_uleb128(ls);
       firstline = bcread_uleb128(ls);
       numline = bcread_uleb128(ls);
+      ofsdeclname = bcread_uleb128(ls);
     }
   }
 
@@ -361,17 +361,16 @@ GCproto *lj_bcread_proto(LexState *ls)
   pt->numline = numline;
   if (sizedbg) {
     MSize sizeli = (sizebc-1) * sizeof(BCLine);
-    setmref(pt->declname, (char *)pt + ofsdbg);
-    setmref(pt->lineinfo, (char *)pt + ofsdbg + ndeclname);
-    setmref(pt->uvinfo, (char *)pt + ofsdbg + ndeclname + sizeli);
+    setmref(pt->lineinfo, (char *)pt + ofsdbg);
+    setmref(pt->uvinfo, (char *)pt + ofsdbg + sizeli);
+    setmref(pt->declname, (char *)pt + ofsdbg + ofsdeclname);
     bcread_dbg(ls, pt, sizedbg);
     setmref(pt->varinfo, bcread_varinfo(pt));
-    lua_assert(strlen(pt->declname)+1 == ndeclname);
   } else {
-    setmref(pt->declname, NULL);
     setmref(pt->lineinfo, NULL);
     setmref(pt->uvinfo, NULL);
     setmref(pt->varinfo, NULL);
+    setmref(pt->declname, NULL);
   }
   return pt;
 }
diff --git a/src/lj_bcwrite.c b/src/lj_bcwrite.c
index 5167c731d3..353a677cf6 100644
--- a/src/lj_bcwrite.c
+++ b/src/lj_bcwrite.c
@@ -210,7 +210,7 @@ static char *bcwrite_bytecode(BCWriteCtx *ctx, char *p, GCproto *pt)
 /* Write prototype. */
 static void bcwrite_proto(BCWriteCtx *ctx, GCproto *pt)
 {
-  MSize sizedbg = 0;
+  MSize sizedbg = 0, ofsdeclname = 0;
   char *p;
   const char *declname = pt->declname ? proto_declname(pt) : "";
 
@@ -239,13 +239,15 @@ static void bcwrite_proto(BCWriteCtx *ctx, GCproto *pt)
   p = lj_strfmt_wuleb128(p, pt->sizekn);
   p = lj_strfmt_wuleb128(p, pt->sizebc-1);
   if (!ctx->strip) {
-    if (proto_lineinfo(pt))
-      sizedbg = pt->sizept - (MSize)((char *)proto_declname(pt) - (char *)pt);
+    if (proto_lineinfo(pt)) {
+      sizedbg = pt->sizept - (MSize)((char *)proto_lineinfo(pt) - (char *)pt);
+      ofsdeclname = (MSize)((char*)proto_declname(pt) - (char *)proto_lineinfo(pt));
+    }
     p = lj_strfmt_wuleb128(p, sizedbg);
     if (sizedbg) {
-      p = lj_strfmt_wuleb128(p, strlen(declname)+1);
       p = lj_strfmt_wuleb128(p, pt->firstline);
       p = lj_strfmt_wuleb128(p, pt->numline);
+      p = lj_strfmt_wuleb128(p, ofsdeclname);
     }
   }
 
@@ -261,7 +263,7 @@ static void bcwrite_proto(BCWriteCtx *ctx, GCproto *pt)
   /* Write debug info, if not stripped. */
   if (sizedbg) {
     p = lj_buf_more(&ctx->sb, sizedbg);
-    p = lj_buf_wmem(p, declname, sizedbg);
+    p = lj_buf_wmem(p, proto_lineinfo(pt), sizedbg);
     setsbufP(&ctx->sb, p);
   }
 
diff --git a/src/lj_obj.h b/src/lj_obj.h
index 9d9349ef86..fc6022ef83 100644
--- a/src/lj_obj.h
+++ b/src/lj_obj.h
@@ -311,10 +311,10 @@ typedef struct GCproto {
   GCRef chunkname;	/* Name of the chunk this function was defined in. */
   BCLine firstline;	/* First line of the function definition. */
   BCLine numline;	/* Number of lines for the function definition. */
-  MRef declname;	/* Declared name of function (null-terminated). */
   MRef lineinfo;	/* Map from bytecode ins. to source line. */
   MRef uvinfo;		/* Upvalue names. */
   MRef varinfo;		/* Names and compressed extents of local variables. */
+  MRef declname;	/* Declared name of function (null-terminated). */
 } GCproto;
 
 /* Flags for prototype. */
@@ -345,10 +345,10 @@ typedef struct GCproto {
 
 #define proto_chunkname(pt)	(strref((pt)->chunkname))
 #define proto_chunknamestr(pt)	(strdata(proto_chunkname((pt))))
-#define proto_declname(pt)	(mref((pt)->declname, const char))
 #define proto_lineinfo(pt)	(mref((pt)->lineinfo, const uint32_t))
 #define proto_uvinfo(pt)	(mref((pt)->uvinfo, const uint8_t))
 #define proto_varinfo(pt)	(mref((pt)->varinfo, const uint8_t))
+#define proto_declname(pt)	(mref((pt)->declname, const char))
 
 /* -- Upvalue object ------------------------------------------------------ */
 
diff --git a/src/lj_parse.c b/src/lj_parse.c
index 1e948d97ce..e9672f00d8 100644
--- a/src/lj_parse.c
+++ b/src/lj_parse.c
@@ -1366,20 +1366,13 @@ static void fs_fixup_line(FuncState *fs, GCproto *pt,
 }
 
 /* Prepare variable info for prototype. */
-static size_t fs_prep_var(LexState *ls, FuncState *fs, size_t *ofsvar, const char *declname)
+static size_t fs_prep_var(LexState *ls, FuncState *fs, size_t *ofsvar,
+                          size_t *ofsdeclname, const char *declname)
 {
   VarInfo *vs =ls->vstack, *ve;
   MSize i, n;
   BCPos lastpc;
   lj_buf_reset(&ls->sb);  /* Copy to temp. string buffer. */
-  /* Store function declaration name. */
-  {
-    char *p;
-    int len = strlen(declname) + 1;
-    p = lj_buf_more(&ls->sb, len);
-    p = lj_buf_wmem(p, declname, len);
-    setsbufP(&ls->sb, p);
-  }
   /* Store upvalue names. */
   for (i = 0, n = fs->nuv; i < n; i++) {
     GCstr *s = strref(vs[fs->uvmap[i]].name);
@@ -1412,16 +1405,24 @@ static size_t fs_prep_var(LexState *ls, FuncState *fs, size_t *ofsvar, const cha
     }
   }
   lj_buf_putb(&ls->sb, '\0');  /* Terminator for varinfo. */
+  /* Store function declaration name. */
+  *ofsdeclname = sbuflen(&ls->sb);
+  {
+    char *p;
+    int len = strlen(declname) + 1;
+    p = lj_buf_more(&ls->sb, len);
+    p = lj_buf_wmem(p, declname, len);
+    setsbufP(&ls->sb, p);
+  }
   return sbuflen(&ls->sb);
 }
 
 /* Fixup variable info for prototype. */
-static void fs_fixup_var(LexState *ls, GCproto *pt, uint8_t *p, size_t ofsvar)
+static void fs_fixup_var(LexState *ls, GCproto *pt, uint8_t *p, size_t ofsvar, size_t ofsdeclname)
 {
-  int ndeclname = strlen((char*)p)+1;
-  setmref(pt->declname, p);
-  setmref(pt->uvinfo, p + ndeclname);
+  setmref(pt->uvinfo, p);
   setmref(pt->varinfo, (char *)p + ofsvar);
+  setmref(pt->declname, (char*)p + ofsdeclname);
   memcpy(p, sbufB(&ls->sb), sbuflen(&ls->sb));  /* Copy from temp. buffer. */
 }
 
@@ -1481,7 +1482,7 @@ static GCproto *fs_finish(LexState *ls, BCLine line, char *declname)
   lua_State *L = ls->L;
   FuncState *fs = ls->fs;
   BCLine numline = line - fs->linedefined;
-  size_t sizept, ofsk, ofsuv, ofsli, ofsdbg, ofsvar;
+  size_t sizept, ofsk, ofsuv, ofsli, ofsdbg, ofsvar, ofsdeclname;
   GCproto *pt;
 
   /* Apply final fixups. */
@@ -1493,7 +1494,7 @@ static GCproto *fs_finish(LexState *ls, BCLine line, char *declname)
   ofsk = sizept; sizept += fs->nkn*sizeof(TValue);
   ofsuv = sizept; sizept += ((fs->nuv+1)&~1)*2;
   ofsli = sizept; sizept += fs_prep_line(fs, numline);
-  ofsdbg = sizept; sizept += fs_prep_var(ls, fs, &ofsvar, declname);
+  ofsdbg = sizept; sizept += fs_prep_var(ls, fs, &ofsvar, &ofsdeclname, declname);
 
   /* Allocate prototype and initialize its fields. */
   pt = (GCproto *)lj_mem_newgco(L, (MSize)sizept);
@@ -1511,7 +1512,7 @@ static GCproto *fs_finish(LexState *ls, BCLine line, char *declname)
   fs_fixup_k(fs, pt, (void *)((char *)pt + ofsk));
   fs_fixup_uv1(fs, pt, (uint16_t *)((char *)pt + ofsuv));
   fs_fixup_line(fs, pt, (void *)((char *)pt + ofsli), numline);
-  fs_fixup_var(ls, pt, (uint8_t *)((char *)pt + ofsdbg), ofsvar);
+  fs_fixup_var(ls, pt, (uint8_t *)((char *)pt + ofsdbg), ofsvar, ofsdeclname);
 
   L->top--;  /* Pop table of constants. */
   ls->vtop = fs->vbase;  /* Reset variable stack. */