diff --git a/dlls/winhttp/session.c b/dlls/winhttp/session.c
index f2ed72bc1ae..56e776da8be 100644
--- a/dlls/winhttp/session.c
+++ b/dlls/winhttp/session.c
@@ -1297,7 +1297,7 @@ static WCHAR *build_wpad_url( const char *hostname, const struct addrinfo *ai )
 
 static BOOL get_system_proxy_autoconfig_url( char *buf, DWORD buflen )
 {
-#ifdef HAVE_CORESERVICES_CORESERVICES_H
+#if defined(MAC_OS_X_VERSION_10_6) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
     CFDictionaryRef settings = CFNetworkCopySystemProxySettings();
     const void *ref;
     BOOL ret = FALSE;