Check whether TARGET_OS_* defines are defined before checking their
value to fix build failure of software that uses tidy on Mac OS X 10.6
(which doesn't define these) when using clang 11 or later (which
MacPorts now does) and remove incorrect use of TARGET_OS_MAC.
https://github.com/htacg/tidy-html5/issues/1030
--- include/tidyplatform.h.orig	2021-07-10 15:53:56.000000000 -0500
+++ include/tidyplatform.h	2022-03-23 03:03:02.000000000 -0500
@@ -115,16 +115,18 @@
 #  define MAC_OS_X
 #  ifndef PLATFORM_NAME
 #    include "TargetConditionals.h"
-#    if TARGET_OS_IOS
-#      define PLATFORM_NAME "Apple iOS"
-#    elif TARGET_OS_MAC
-#      define PLATFORM_NAME "Apple macOS"
-#    elif TARGET_OS_TV
-#      define PLATFORM_NAME "Apple tvOS"
-#    elif TARGET_OS_WATCH
-#      define PLATFORM_NAME "Apple watchOS"
+#    if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
+#      if defined(TARGET_OS_MACCATALYST) && TARGET_OS_MACCATALYST
+#        define PLATFORM_NAME "Apple macOS"
+#      elif defined(TARGET_OS_TV) && TARGET_OS_TV
+#        define PLATFORM_NAME "Apple tvOS"
+#      elif defined(TARGET_OS_WATCH) && TARGET_OS_WATCH
+#        define PLATFORM_NAME "Apple watchOS"
+#      else
+#        define PLATFORM_NAME "Apple iOS"
+#      endif
 #    else
-#      define PLATFORM_NAME "Apple Unknown OS"
+#      define PLATFORM_NAME "Apple macOS"
 #    endif
 #  endif
 #endif