diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -10,7 +10,9 @@
 include(CheckProblematicConfigurations)
 include(HandleLLVMStdlib)
 include(CheckCCompilerFlag)
+include(CheckCSourceCompiles)
 include(CheckCXXCompilerFlag)
+include(CheckCXXSourceCompiles)
 include(CheckSymbolExists)
 include(CMakeDependentOption)
 include(LLVMProcessSources)