Index: configure.ac
==================================================================
--- configure.ac
+++ configure.ac
@@ -1488,10 +1488,11 @@
 	])
 	AC_CHECK_HEADER(netinet/tcp.h, [
 		AC_DEFINE(OF_HAVE_NETINET_TCP_H, 1,
 			[Whether we have netinet/tcp.h])
 	])
+	AC_CHECK_HEADERS(linux/mptcp.h)
 	AC_CHECK_HEADER(netinet/sctp.h, [
 		AC_DEFINE(OF_HAVE_SCTP, 1, [Whether we have SCTP])
 		AC_DEFINE(OF_HAVE_NETINET_SCTP_H, 1,
 			[Whether we have netinet/sctp.h])
 		AC_SUBST(USE_SRCS_SCTP, '${SRCS_SCTP}')

Index: src/OFTCPSocket.m
==================================================================
--- src/OFTCPSocket.m
+++ src/OFTCPSocket.m
@@ -51,11 +51,11 @@
 #import "OFGetOptionFailedException.h"
 #import "OFNotImplementedException.h"
 #import "OFNotOpenException.h"
 #import "OFSetOptionFailedException.h"
 
-#ifdef OF_LINUX
+#ifdef HAVE_LINUX_MPTCP_H
 # include <linux/mptcp.h>
 #endif
 
 #if defined(OF_MACOS) || defined(OF_IOS)
 # ifndef AF_MULTIPATH