diff --git a/cmake/msvc_legacy_quirks.cmake b/cmake/msvc_legacy_quirks.cmake
index d975d2c42..25e9b56c1 100644
--- a/cmake/msvc_legacy_quirks.cmake
+++ b/cmake/msvc_legacy_quirks.cmake
@@ -57,10 +57,10 @@ endif()
 # Note we don't set WIN32 or _WINDOWS because
 # CMake provides that for us. As a sanity check make sure the option
 # is present.
-if (NOT "${CMAKE_CXX_FLAGS}" MATCHES "/D[ ]*WIN32")
+if (NOT "${CMAKE_CXX_FLAGS}" MATCHES "[-/]D[ ]*WIN32")
   message(FATAL_ERROR "\"/D WIN32\" is missing")
 endif()
-if (NOT "${CMAKE_CXX_FLAGS}" MATCHES "/D[ ]*_WINDOWS")
+if (NOT "${CMAKE_CXX_FLAGS}" MATCHES "[-/]D[ ]*_WINDOWS")
   message(FATAL_ERROR "\"/D _WINDOWS\" is missing")
 endif()