Index: configure.ac
==================================================================
--- configure.ac
+++ configure.ac
@@ -126,11 +126,10 @@
 	AC_DEFINE(OF_THREADS, 1, [Whether we have threads])
 	AC_SUBST(OFTHREAD_M, "OFThread.m")
 	AC_SUBST(THREADING_H, "threading.h")
 
 	AC_CHECK_FUNC(objc_sync_enter,, [
-		AC_SUBST(OBJC_SYNC, "objc_sync")
 		AC_SUBST(OBJC_SYNC_M, "objc_sync.m")
 		AC_DEFINE(NEED_OBJC_SYNC_INIT, 1,
 			[Whether objc_sync_init needs to be called])])
 fi
 

Index: extra.mk.in
==================================================================
--- extra.mk.in
+++ extra.mk.in
@@ -1,10 +1,9 @@
 ASPRINTF_M = @ASPRINTF_M@
-OBJC_SYNC = @OBJC_SYNC@
 OBJC_SYNC_M = @OBJC_SYNC_M@
 OFPLUGIN_M = @OFPLUGIN_M@
 OFTHREAD_M = @OFTHREAD_M@
 TESTPLUGIN = @TESTPLUGIN@
 WS2_LIBS = @WS2_LIBS@
 TESTS = @TESTS@
 TEST_LAUNCHER = @TEST_LAUNCHER@
 THREADING_H = @THREADING_H@