build: add --enable-werror
This allows enabling -Werror in a consistent way. Note that this is
different from just specifiying it in CFLAGS, since that would either
break configure tests (if done on ./configure), or would override
configure's CFLAGS (if done on make).
Using --enable-werror instead provides a new WERROR variable that is
additionally used during make with a consistent set of warning flags.
The tests/ directory is exempt. (Rationale being, better to have more
tests than pedantically complain about them.)
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/zebra/Makefile.am b/zebra/Makefile.am
index 4808791..7dcbd66 100644
--- a/zebra/Makefile.am
+++ b/zebra/Makefile.am
@@ -20,7 +20,7 @@
othersrc = zebra_fpm_netlink.c
endif
-AM_CFLAGS = $(PICFLAGS)
+AM_CFLAGS = $(PICFLAGS) $(WERROR)
AM_LDFLAGS = $(PILDFLAGS)
sbin_PROGRAMS = zebra