diff --git a/hw/xquartz/pbproxy/Makefile.am b/hw/xquartz/pbproxy/Makefile.am
index 188664259..7b8685d7a 100644
--- a/hw/xquartz/pbproxy/Makefile.am
+++ b/hw/xquartz/pbproxy/Makefile.am
@@ -2,6 +2,7 @@ AM_CPPFLAGS=-F/System/Library/Frameworks/ApplicationServices.framework/Framework
 	-DLAUNCHD_ID_PREFIX=\"$(LAUNCHD_ID_PREFIX)\"
 
 AM_CFLAGS=$(XPBPROXY_CFLAGS) 
+AM_OBJCFLAGS=$(XPBPROXY_CFLAGS)
 
 noinst_LTLIBRARIES = libxpbproxy.la
 libxpbproxy_la_SOURCES = \