diff --git a/CMakeLists.txt b/CMakeLists.txt
index 40c4b8d..bd4798d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,10 @@ execute_process(
   WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/tools/antlr
 )
 
+SET(WITH_LIBCXX OFF CACHE BOOL "")
+add_subdirectory(${CMAKE_SOURCE_DIR}/tools/antlr/antlr4/runtime/Cpp/ EXCLUDE_FROM_ALL)
+include_directories(${CMAKE_SOURCE_DIR}/tools/antlr/antlr4/runtime/Cpp/runtime/src)
+
 # Function
 #   ANTLR(<file.g4>)
 #
@@ -78,16 +82,6 @@ function(target_set_common target)
   endif()
 endfunction()
 
-# Build the ANTLR runtime.
-set(CMAKE_CXX_STANDARD 17)
-add_subdirectory(
-  ${CMAKE_SOURCE_DIR}/tools/antlr/cpp_runtime/
-  ${CMAKE_CURRENT_BINARY_DIR}/antlr
-  EXCLUDE_FROM_ALL
-)
-set_property(TARGET antlr4_static PROPERTY CXX_STANDARD 17)
-include_directories(${CMAKE_SOURCE_DIR}/tools/antlr/cpp_runtime/runtime/src)
-
 #-------------------------------------------------------------------------------
 
 add_subdirectory(src)
diff --git a/tools/antlr/CMakeLists.txt.patch b/tools/antlr/CMakeLists.txt.patch
deleted file mode 100644
index a8c772f..0000000
--- a/tools/antlr/CMakeLists.txt.patch
+++ /dev/null
@@ -1,28 +0,0 @@
-97,123d96
-< # Compiler-specific C++11 activation.
-< if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU" OR "${CMAKE_CXX_COMPILER_ID}" MATCHES "Intel")
-<     execute_process(
-<         COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION)
-<     # Just g++-5.0 and greater contain <codecvt> header. (test in ubuntu)
-<     if (NOT (GCC_VERSION VERSION_GREATER 5.0 OR GCC_VERSION VERSION_EQUAL 5.0))
-<         message(FATAL_ERROR "${PROJECT_NAME} requires g++ 5.0 or greater.")
-<     endif ()
-< elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND APPLE)
-<     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-< elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND CMAKE_SYSTEM_NAME MATCHES "Linux")
-<     execute_process(
-<         COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE CLANG_VERSION)
-<     if (NOT (CLANG_VERSION VERSION_GREATER 4.2.1 OR CLANG_VERSION VERSION_EQUAL 4.2.1))
-<         message(FATAL_ERROR "${PROJECT_NAME} requires clang 4.2.1 or greater.")
-<     endif ()
-<     # You can use libc++ to compile this project when g++ is NOT greater than or equal to 5.0.
-<     if (WITH_LIBCXX)
-<         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-<     endif()
-< elseif ( MSVC_VERSION GREATER 1800 OR MSVC_VERSION EQUAL 1800 )
-<   # Visual Studio 2012+ supports c++11 features 
-< else ()
-<     message(FATAL_ERROR "Your C++ compiler does not support C++11.")
-< endif ()
-< 
-< 
diff --git a/tools/antlr/download_and_patch.sh b/tools/antlr/download_and_patch.sh
index a46a9ef..ae96b24 100755
--- a/tools/antlr/download_and_patch.sh
+++ b/tools/antlr/download_and_patch.sh
@@ -6,15 +6,10 @@ then
   exit
 fi
 
-mkdir cpp_runtime
+mkdir -p cpp_runtime
 
-## Download ANTLR and the CPP runtime
-curl http://www.antlr.org/download/antlr-4.7.1-complete.jar -Lo antlr.jar
-curl http://www.antlr.org/download/antlr4-cpp-runtime-4.7.1-source.zip -Lo cpp_runtime/archive.zip
+## Download the ANTLR executable.
+curl http://www.antlr.org/download/antlr-4.8-complete.jar -L -o antlr.jar
 
-## Unzip cpp runtime
-cd cpp_runtime
-unzip *.zip
-
-## Patch the cpp runtime CMakeLists.txt.
-patch CMakeLists.txt < ../CMakeLists.txt.patch
+## Download the C++ runtime.
+git clone --depth 1 https://github.com/antlr/antlr4 -b 4.8