diff -up ClanLib-2.3.7/configure.ac~ ClanLib-2.3.7/configure.ac
--- ClanLib-2.3.7/configure.ac~	2012-04-11 08:55:49.000000000 +0200
+++ ClanLib-2.3.7/configure.ac	2017-02-21 11:57:23.482504683 +0100
@@ -119,7 +119,6 @@ case $target in
 	*)
 		X11="yes"
 		WIN32="no"
-		CXXFLAGS="$CXXFLAGS -std=c++0x"
 		;;
 esac
 
@@ -259,7 +258,7 @@ if test "$use_sse2" != "no"; then
 fi
 
 if test "$WIN32" = "no"; then
-	extra_CFLAGS_clanCore="$extra_CFLAGS_clanCore -pthread -std=c++0x"
+	extra_CFLAGS_clanCore="$extra_CFLAGS_clanCore -pthread"
 else
 	extra_CFLAGS_clanCore="$extra_CFLAGS_clanCore -mthreads -std=c++0x"
 fi