diff --git a/ripngd/Makefile.am b/ripngd/Makefile.am
index 9bd14ba..0487459 100644
--- a/ripngd/Makefile.am
+++ b/ripngd/Makefile.am
@@ -4,7 +4,7 @@
 DEFS = @DEFS@ -DSYSCONFDIR=\"$(sysconfdir)/\"
 INSTALL_SDATA=@INSTALL@ -m 600
 
-AM_CFLAGS = $(PICFLAGS)
+AM_CFLAGS = $(PICFLAGS) $(WERROR)
 AM_LDFLAGS = $(PILDFLAGS)
 
 noinst_LIBRARIES = libripng.a