Hi, Sergey,

<snipped>

thanks for the patch! LGTM with a minor:

probably line 10 needs more whitespaces:

 >      do local a,b,c,d,e,f,g,h,i,j,k,l,m,n end -- Ensure bigger frame 
size.

Fixed thanks!
See the iterative patch below.

===================================================================
diff --git a/test/LuaJIT-tests/lang/gc_stack.lua b/test/LuaJIT-tests/lang/gc_stack.lua
index 8aee57e3..d05d4402 100644
--- a/test/LuaJIT-tests/lang/gc_stack.lua
+++ b/test/LuaJIT-tests/lang/gc_stack.lua
@@ -7,7 +7,10 @@ do --- Marking sparse stack.
     else
       return t[k] -- Leaves holes in each frame.
     end
-    do local a,b,c,d,e,f,g,h,i,j,k,l,m,n end -- Ensure bigger frame size.
+    do
+      -- Ensure bigger frame size.
+      local a, b, c, d, e, f, g, h, i, j, k, l, m, n
+    end
   end})
   local x = t[50]
 end
===================================================================