diff --git a/Doxyfile b/Doxyfile
index 170e18a8..2d91051d 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -1512,6 +1512,9 @@ INCLUDE_FILE_PATTERNS  =
 PREDEFINED             = HAVE_IPV6 \
                          HAVE_LIBSSL \
                          HAVE_LSTAT \
+                         HAVE_PTHREAD \
+                         HAVE_THREADED_DNS \
+                         HAVE_ICU \
                          _NO_CSOCKET_NS \
                          _MODULES