From https://github.com/macports/macports-legacy-support/blob/0f1292b4734aac30188ee03561ecd1430a255062/include/netdb.h#L23

--- src/vmime/platforms/posix/posixSocket.cpp	2024-12-08 09:04:25.000000000 +0800
+++ src/vmime/platforms/posix/posixSocket.cpp	2024-12-08 09:19:54.000000000 +0800
@@ -59,6 +59,11 @@
 #endif
 
 
+#ifndef AI_NUMERICSERV
+#define AI_NUMERICSERV 0x00001000
+#endif
+
+
 // Workaround for detection of strerror_r variants
 #if VMIME_HAVE_STRERROR_R
 
