diff --git a/libc/cmake/modules/LLVMLibCObjectRules.cmake b/libc/cmake/modules/LLVMLibCObjectRules.cmake
--- a/libc/cmake/modules/LLVMLibCObjectRules.cmake
+++ b/libc/cmake/modules/LLVMLibCObjectRules.cmake
@@ -1,7 +1,12 @@
 set(OBJECT_LIBRARY_TARGET_TYPE "OBJECT_LIBRARY")
 
 function(_get_common_compile_options output_var)
-  set(${output_var} -fpie ${LLVM_CXX_STD_default} -ffreestanding ${LIBC_COMPILE_OPTIONS_DEFAULT} ${ARGN} PARENT_SCOPE)
+  set(${output_var} ${LLVM_CXX_STD_default} ${LIBC_COMPILE_OPTIONS_DEFAULT} ${ARGN} PARENT_SCOPE)
+  if(${LIBC_TARGET_OS} STREQUAL "windows")
+    set(${output_var} /Qfreestanding PARENT_SCOPE)
+  else()
+   set(${output_var} -fpie -ffreestanding PARENT_SCOPE)
+  endif()
 endfunction()
 
 # Rule which is essentially a wrapper over add_library to compile a set of