Experiments in lj-881-fix-lua-concat.test.c [TMP]

https://github.com/tarantool/luajit/actions/runs/12831238829/job/35781196235

 =================================================================
==765154==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 256 byte(s) in 1 object(s) allocated from:
    #0 0x496949 in realloc (/opt/actions-runner/_work/_temp/build-12831238829/test/tarantool-c-tests/lj-881-fix-lua-concat.c_test+0x496949)
    #1 0x4da87a in lj_mem_realloc /opt/actions-runner/_work/luajit/luajit/src/lj_gc.c:869:7
    #2 0x53f2a8 in lj_ir_growtop /opt/actions-runner/_work/luajit/luajit/src/lj_ir.c:81:23
    #3 0x53f5f1 in lj_ir_nextins /opt/actions-runner/_work/luajit/luajit/src/lj_iropt.h:34:40
    #4 0x53f5f1 in lj_ir_emit /opt/actions-runner/_work/luajit/luajit/src/lj_ir.c:118:15
    #5 0x5cc2ea in lj_record_setup /opt/actions-runner/_work/luajit/luajit/src/lj_record.c:2651:3
    #6 0x5440f0 in trace_state /opt/actions-runner/_work/luajit/luajit/src/lj_trace.c:681:7
    #7 0x58c045 in lj_vm_cpcall /opt/actions-runner/_work/_temp/build-12831238829/src/lj_vm.S:1262

SUMMARY: AddressSanitizer: 256 byte(s) leaked in 1 allocation(s).

test/tarantool-c-tests/lj-881-fix-lua-concat.test.c

@@ -6,93 +6,74 @@
 #include "test.h"
 #include "utils.h"
 
-/*
- * This test demonstrates LuaJIT's incorrect behaviour when
- * calling `lua_concat()` with userdata with the __concat metamethod.
- * See https://github.com/LuaJIT/LuaJIT/issues/881 for details.
- */
-
-#define TYPE_NAME "int"
-
-#define TEST_VALUE 100
-#define TOSTR(s) #s
-#define CONCAT(A, B) A TOSTR(B)
+static int bbb(lua_State *L) {
+	luaL_dostring(L, "local function varg_func(...) end return function() return varg_func() end");
+	luaL_dostring(L, "repeat until nil > 1");
+	return 0;
+}
 
-static int __concat(lua_State *L)
-{
-	const char *s = luaL_checkstring(L, 1);
-	int *n = (int *)luaL_checkudata(L, 2, TYPE_NAME);
-	/* Do non-default concatenation. */
-	lua_pushfstring(L, "%s + %d", s, *n);
+static int aaa(lua_State *L) {
+	(void)L;
+	luaL_dostring(L, "local function varg_func(...) end return function() return varg_func() end");
+	lua_pushcfunction(L, (lua_CFunction)bbb);
+	lua_pcall(L, 0, 0, 0);
+	luaL_dostring(L, "local function varg_func(...) end return function() return varg_func() end");
 	return 1;
 }
 
-static const luaL_Reg mt[] = {
-	{ "__concat", __concat },
-	{ NULL, NULL}
-};
-
-static int lua_concat_testcase(void *test_state)
+static void jit_attach(lua_State *L, void *cb, const char *event)
 {
-	/* Setup. */
-	lua_State *L = test_state;
-	const int top = 4;
-
-	/* Create metatable and put it to the Lua registry. */
-	luaL_newmetatable(L, TYPE_NAME);
-	/* Fill metatable. */
-	luaL_register(L, 0, mt);
-	lua_pop(L, 1);
+	lua_getglobal(L, "jit");
+	lua_getfield(L, -1, "attach");
+	lua_pushcfunction(L, (lua_CFunction)cb);
+	if (event != NULL) {
+		lua_pushstring(L, event);
+	} else {
+		lua_pushnil(L);
+	}
+	lua_pcall(L, 2, 0, 0);
+}
 
-	assert_int_equal(lua_gettop(L), 0);
+static int trace_cb(lua_State *L) {
+	(void)L;
+	/* is_cb_called = 1; */
+	/* luaL_dostring(L, "repeat until nil > 1"); */
+	/* luaL_dostring(L, "local function varg_func(...) end return function() return varg_func() end"); */
+	/* luaL_dostring(L, "error()"); */
+	lua_pushcfunction(L, (lua_CFunction)aaa);
+	lua_pcall(L, 0, 0, 0);
+	return 0;
+}
 
-	lua_pushliteral(L, "C");
-	lua_pushliteral(L, "B");
-	lua_pushliteral(L, "A");
+int main(void)
+{
+	lua_State *L = luaL_newstate();
+	luaL_openlibs(L);
+	luaL_dostring(L, "jit.opt.start('hotloop=1')");
 
-	int *n = (int *)lua_newuserdata(L, sizeof(*n));
-	*n = 100;
+	jit_attach(L, (void *)trace_cb, "trace");
 
-	luaL_getmetatable(L, TYPE_NAME);
-	lua_setmetatable(L, -2);
+	/* Frame with a broken Lua code. */
+	luaL_dostring(L, "repeat until nil > 1");
+	/* luaL_dostring(L, "local function varg_func(...) end return function() return varg_func() end"); */
 
-	assert_int_equal(lua_gettop(L), top);
+	/* Frame with C function. */
+	/* lua_getfield(L, LUA_GLOBALSINDEX, "print"); */
+	/* lua_pcall(L, 0, 0, 0); */
 
-	/* Test body. */
+	/* lua_pushcfunction(L, (lua_CFunction)aaa); */
+	/* lua_pcall(L, 0, 0, 0); */
 
-	/*
-	 * void lua_concat (lua_State *L, int n);
-	 *
-	 * Concatenates the n values at the top of the stack,
-	 * pops them, and leaves the result at the top. If n is 1,
-	 * the result is the single value on the stack; if n is 0,
-	 * the result is the empty string [1].
-	 *
-	 * 1. https://www.lua.org/manual/5.1/manual.html
-	 */
+	/* lua_pushcfunction(L, (lua_CFunction)bbb); */
+	/* lua_pushcfunction(L, (lua_CFunction)aaa); */
+	/* lua_pcall(L, 0, 0, -2); */
 
-	/* Concatenate two elements on the top. */
-	lua_concat(L, 2);
+	jit_attach(L, (void *)trace_cb, NULL);
 
-	const char *str = lua_tostring(L, -1);
-	assert_int_equal(lua_gettop(L), top - 2 + 1);
-	const char expected_str[] = CONCAT("A + ", TEST_VALUE);
-	assert_str_equal(str, expected_str);
+	lua_State *LL = utils_lua_init();
+	utils_lua_close(LL);
 
 	/* Teardown. */
 	lua_settop(L, 0);
-
-	return TEST_EXIT_SUCCESS;
-}
-
-int main(void)
-{
-	lua_State *L = utils_lua_init();
-	const struct test_unit tgroup[] = {
-		test_unit_def(lua_concat_testcase),
-	};
-	const int test_result = test_run_group(tgroup, L);
-	utils_lua_close(L);
-
-	return test_result;
+	return 0;
 }