diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -4,6 +4,10 @@
 
 set(CMAKE_BUILD_WITH_INSTALL_NAME_DIR ON)
 
+if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.20.0")
+  cmake_policy(SET CMP0116 OLD)
+endif()
+
 if(NOT DEFINED LLVM_VERSION_MAJOR)
   set(LLVM_VERSION_MAJOR 13)
 endif()