Bug: stack overflow with nesting of coroutine.close

testes/cstack.lua

@@ -84,6 +84,32 @@ do   -- bug in 5.4.0
 end
 
 
+do    -- bug since 5.4.0
+  local count = 0
+  print("chain of 'coroutine.close'")
+  -- create N coroutines forming a list so that each one, when closed,
+  -- closes the previous one. (With a large enough N, previous Lua
+  -- versions crash in this test.)
+  local coro = false
+  for i = 1, 1000 do
+    local previous = coro
+    coro = coroutine.create(function()
+      local cc <close> = setmetatable({}, {__close=function()
+        count = count + 1
+        if previous then
+          assert(coroutine.close(previous))
+        end
+      end})
+      coroutine.yield()   -- leaves 'cc' pending to be closed
+    end)
+    assert(coroutine.resume(coro))  -- start it and run until it yields
+  end
+  local st, msg = coroutine.close(coro)
+  assert(not st and string.find(msg, "C stack overflow"))
+  print("final count: ", count)
+end
+
+
 do
   print("nesting of resuming yielded coroutines")
   local count = 0