diff --git a/libc/cmake/modules/LLVMLibCRules.cmake b/libc/cmake/modules/LLVMLibCRules.cmake
--- a/libc/cmake/modules/LLVMLibCRules.cmake
+++ b/libc/cmake/modules/LLVMLibCRules.cmake
@@ -220,6 +220,10 @@
 endfunction(add_entrypoint_library)
 
 function(add_libc_unittest target_name)
+  if(NOT LLVM_INCLUDE_TESTS)
+    return()
+  endif()
+
   cmake_parse_arguments(
     "LIBC_UNITTEST"
     "" # No optional arguments