From 0f1cd0eba99ea6d383e75b9ae488d00ad541c210 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 13 Jul 2020 13:37:01 -0300
Subject: [PATCH] Added test for fix 127e7a6c894

---
 testes/gengc.lua | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/testes/gengc.lua b/testes/gengc.lua
index b02f471b..4e80dd7e 100644
--- a/testes/gengc.lua
+++ b/testes/gengc.lua
@@ -37,6 +37,33 @@ do
 end
 
 
+do   -- bug in 5.4.0
+-- When an object aged OLD1 is finalized, it is moved from the list
+-- 'finobj' to the *beginning* of the list 'allgc', but that part of the
+-- list was not being visited by 'markold'.
+  local A = {}
+  A[1] = false     -- old anchor for object
+
+  -- obj finalizer
+  local function gcf (obj)
+    A[1] = obj     -- anchor object
+    assert(not T or T.gcage(obj) == "old1")
+    obj = nil      -- remove it from the stack
+    collectgarbage("step", 0)   -- do a young collection
+    print(getmetatable(A[1]).x)   -- metatable was collected
+  end
+
+  collectgarbage()   -- make A old
+  local obj = {}     -- create a new object
+  collectgarbage("step", 0)   -- make it a survival
+  assert(not T or T.gcage(obj) == "survival")
+  setmetatable(obj, {__gc = gcf, x = "ok"})   -- create its metatable
+  assert(not T or T.gcage(getmetatable(obj)) == "new")
+  obj = nil   -- clear object
+  collectgarbage("step", 0)   -- will call obj's finalizer
+end
+
+
 if T == nil then
   (Message or print)('\n >>> testC not active: \z
                              skipping some generational tests <<<\n')
@@ -72,6 +99,9 @@ do
   assert(debug.getuservalue(U).x[1] == 234)
 end
 
+-- just to make sure
+assert(collectgarbage'isrunning')
+
 
 
 -- just to make sure