diff --git a/src/lj_meta.c b/src/lj_meta.c
index c72673cbee..69071454b2 100644
--- a/src/lj_meta.c
+++ b/src/lj_meta.c
@@ -246,14 +246,14 @@ TValue *lj_meta_cat(lua_State *L, TValue *top, int left)
   if (left < 0) { left = -left; fromc = 1; }
 #if LJ_HASFFI && defined(LJMAD_RANGE_SYNTAX)               /* LD: 2016.05.14 */
   if (tvisnumber(top) && tvisnumber(top-1) &&
-      (left == 2 || (left == 3 && tvisnumber(top-2)))) {
+      (left == 1 || (left == 2 && tvisnumber(top-2)))) {
     /* Convert 2-3 concatenated numbers into a range, see also rec_cat. */
     if (!ljmad_range_id) {
         GCstr *name = lj_str_newlit(L, "range");
         CTState *cts = ctype_cts(L);
         CType *ct;
         CTypeID id = lj_ctype_getname(cts, &ct, name, 1u<<CT_STRUCT);
-        if (!id) lj_err_optype(L, top-(left-1), LJ_ERR_OPCAT);
+        if (!id) lj_err_optype(L, top-left, LJ_ERR_OPCAT);
         lua_assert(ctype_isstruct(ct->info));
         // fprintf(stderr, "**** id=%d, ctinfo=0x%x, is_struct=%d, name=%s\n",id,
         // ct->info, ctype_isstruct(ct->info), strdata(gcrefp(cts->tab[id].name,GCstr)));
@@ -262,10 +262,10 @@ TValue *lj_meta_cat(lua_State *L, TValue *top, int left)
     /* Allocate cdata struct range. */
     GCcdata *cd = lj_cdata_new(ctype_cts(L), ljmad_range_id, 3*sizeof(double));
     /* Copy start, stop[, step], default step is 1. */
-    top -= left-1;
+    top -= left;
     ((double *)cdataptr(cd))[0] = numV(top);
     ((double *)cdataptr(cd))[1] = numV(top+1);
-    ((double *)cdataptr(cd))[2] = left == 2 ? 1 : numV(top+2);
+    ((double *)cdataptr(cd))[2] = left == 1 ? 1 : numV(top+2);
     setcdataV(L, top, cd);
   } else
 #endif