diff --git a/CMakeLists.txt b/CMakeLists.txt
index c43507b2..d952ac16 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -42,7 +42,7 @@ include(CheckCSourceRuns)
 include(CMakeDependentOption)
 
 check_include_files(ifaddrs.h ZMQ_HAVE_IFADDRS)
-check_include_files(windows.h HAVE_WINDOWS_H)
+check_include_files(windows.h ZMQ_HAVE_WINDOWS)
 check_include_files(sys/uio.h ZMQ_HAVE_UIO)
 check_include_files(sys/eventfd.h ZMQ_HAVE_EVENTFD)
 
diff --git a/builds/cmake/platform.hpp.in b/builds/cmake/platform.hpp.in
index 5f5eb2e0..4a8ae6f0 100644
--- a/builds/cmake/platform.hpp.in
+++ b/builds/cmake/platform.hpp.in
@@ -82,10 +82,7 @@
   #define ZMQ_HAVE_SOLARIS
 #endif
 
-#if defined(WIN32) || defined(_WIN32)
-  #define ZMQ_HAVE_WINDOWS
-#endif
-
+#cmakedefine ZMQ_HAVE_WINDOWS
 
 
 #endif