diff --git a/Utilities/cmcurl/CMakeLists.txt b/Utilities/cmcurl/CMakeLists.txt
index 08bdff57e..32e45615b 100644
--- a/Utilities/cmcurl/CMakeLists.txt
+++ b/Utilities/cmcurl/CMakeLists.txt
@@ -524,12 +524,18 @@ check_include_file("features.h"       HAVE_FEATURES_H)
 if(NOT UNIX)
   check_include_file_concat("ws2tcpip.h"     HAVE_WS2TCPIP_H)
   check_include_file_concat("winsock2.h"     HAVE_WINSOCK2_H)
-endif(NOT UNIX)
+else()
+  set(HAVE_WS2TCPIP_H 0)
+  set(HAVE_WINSOCK2_H 0)
+endif()
 check_include_file_concat("stdio.h"          HAVE_STDIO_H)
 if(NOT UNIX)
   check_include_file_concat("windows.h"      HAVE_WINDOWS_H)
   check_include_file_concat("winsock.h"      HAVE_WINSOCK_H)
-endif(NOT UNIX)
+else()
+  set(HAVE_WINDOWS_H 0)
+  set(HAVE_WINSOCK_H 0)
+endif()
 
 check_include_file_concat("inttypes.h"       HAVE_INTTYPES_H)
 check_include_file_concat("sys/filio.h"      HAVE_SYS_FILIO_H)