diff --git a/Doxyfile b/Doxyfile
--- a/Doxyfile
+++ b/Doxyfile
@@ -195,7 +195,7 @@ EXPAND_ONLY_PREDEF     = YES
 SEARCH_INCLUDES        = YES
 INCLUDE_PATH           =
 INCLUDE_FILE_PATTERNS  =
-PREDEFINED             = ENABLE_NETWORK ENABLE_AI WITH_ZLIB WITH_LZO WITH_PNG WITH_FONTCONFIG WITH_FREETYPE WITH_ICU UNICODE _UNICODE
+PREDEFINED             = ENABLE_NETWORK ENABLE_AI WITH_ZLIB WITH_LZO WITH_LZMA WITH_SDL WITH_PNG WITH_FONTCONFIG WITH_FREETYPE WITH_ICU UNICODE _UNICODE _GNU_SOURCE
 EXPAND_AS_DEFINED      =
 SKIP_FUNCTION_MACROS   = YES
 #---------------------------------------------------------------------------