chore(build): remove CheckLuaObjlen, it is easier to check the Lua version

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/CMakeLists.txt

@@ -127,9 +127,6 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I ${LUA_INCLUDE_DIR}")
 if ("${HAS_LUA_NEWSTATE}$" MATCHES "TRUE")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D LEAN_USE_LUA_NEWSTATE")
 endif()
-if ("${HAS_LUA_OBJLEN}$" MATCHES "TRUE")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D LEAN_USE_LUA_OBJLEN")
-endif()
 
 include_directories(${LEAN_SOURCE_DIR})
 

src/cmake/Modules/CheckLuaObjlen.cc

@@ -1,20 +0,0 @@
-/*
-Copyright (c) 2013 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-
-Author: Leonardo de Moura
-*/
-#include <iostream>
-#include <memory>
-#include <lua.hpp>
-
-// Little program for checking whether lua_objlen is available
-int main() {
-    lua_State * L;
-    L = luaL_newstate();
-    lua_newtable(L);
-    if (lua_objlen(L, -1) == 0)
-        return 0;
-    else
-        return 1;
-}

src/cmake/Modules/FindLua.cmake

@@ -133,18 +133,5 @@ if (LUA_FOUND)
     else()
       message(STATUS "lua_newstate is not supported by your Lua engine, Lean will not be able to track memory consumed by the Lua engine")
     endif()
-
-    try_run(LUA_CHECK2 LUA_CHECK_BUILD2
-      ${LEAN_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp
-      ${LEAN_SOURCE_DIR}/cmake/Modules/CheckLuaObjlen.cc
-      CMAKE_FLAGS -DINCLUDE_DIRECTORIES=${LUA_INCLUDE_DIR}
-      -DLINK_LIBRARIES=${LUA_LIBRARIES}
-      RUN_OUTPUT_VARIABLE LUA_TRY_OUT)
-    if ("${LUA_CHECK2}" MATCHES "0" AND "${LUA_CHECK_BUILD2}$" MATCHES "TRUE")
-      message(STATUS "lua_objlen found")
-      set(HAS_LUA_OBJLEN TRUE)
-    else()
-      message(STATUS "lua_objlen is not available, using lua_rawlen instead")
-    endif()
   endif()
 endif ()