diff --git a/llvm/cmake/modules/CheckAtomic.cmake b/llvm/cmake/modules/CheckAtomic.cmake
index 29f3bdd57f03d..af925f5bf9ec2 100644
--- a/llvm/cmake/modules/CheckAtomic.cmake
+++ b/llvm/cmake/modules/CheckAtomic.cmake
@@ -53,6 +53,8 @@ if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
       message(FATAL_ERROR "Host compiler appears to require libatomic, but cannot find it.")
     endif()
   endif()
+elseif(MSVC)
+  set(HAVE_CXX_ATOMICS_WITHOUT_LIB True)
 endif()
 
 # Check for 64 bit atomic operations.