--- src/shrpx_config.cc~	2017-07-02 10:46:31.000000000 +0200
+++ src/shrpx_config.cc	2017-07-09 22:29:41.000000000 +0200
@@ -43,6 +43,21 @@
 #endif // HAVE_UNISTD_H
 #include <dirent.h>
 
+#ifdef __APPLE__                                                // this block only for Macs
+# ifndef __MAC_OS_X_VERSION_MIN_REQUIRED                        // are AvailabilityMacros.h or Availability.h not yet included?
+#  if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1050     // then for Leopard and later…
+#   include <Availability.h>                                    // …either include this…
+#  else
+#   include <AvailabilityMacros.h>                              // …or include that
+#  endif
+# endif
+# if __MAC_OS_X_VERSION_MIN_REQUIRED < 1060                     // and for some OS versions do this…
+#  ifndef AI_NUMERICSERV
+#   define AI_NUMERICSERV 0
+#  endif
+# endif                                                         // finish OS version discrimination
+#endif                                                          // finish Apple case
+
 #include <cstring>
 #include <cerrno>
 #include <limits>