diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index 0f8ddd87e02c..895f9ab7189d 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -145,6 +145,9 @@ if (LLVM_ENABLE_PROJECTS_USED OR NOT LLVM_ENABLE_PROJECTS STREQUAL "")
         message(FATAL_ERROR "LLVM_ENABLE_PROJECTS requests ${proj} but directory not found: ${PROJ_DIR}")
       endif()
       set(LLVM_EXTERNAL_${upper_proj}_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../${proj}" CACHE STRING "")
+    elseif ("${proj}" IN_LIST LLVM_EXTERNAL_PROJECTS)
+      message(STATUS "${proj} project is enabled")
+      set(SHOULD_ENABLE_PROJECT TRUE)
     else()
       message(STATUS "${proj} project is disabled")
       set(SHOULD_ENABLE_PROJECT FALSE)