autogen.sh: CFLAGS: Add -Werror=implicit-function-declaration

This is not just a style issue.  This should be a hard error, and never
compile.  ISO C89 already had this feature as deprecated.  ISO C99
removed this deprecated feature, for good reasons.  If we compile
ignoring this warning, shadow is not going to behave well.

Cc: Sam James <sam@gentoo.org>
Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

diff --git a/autogen.sh b/autogen.sh
index 881e9770cc387afc94bcde6fcc47f25e88e28eea..eb30a9a166a4b2d0c90b9889329c035877f16e5c 100755 (executable)
--- a/autogen.sh
+++ b/autogen.sh
@@ -3,7 +3,7 @@
 autoreconf -v -f --install "$(dirname "$0")" || exit 1
 
 "$(dirname "$0")"/configure \
-       CFLAGS="-O2 -Wall" \
+       CFLAGS="-O2 -Wall -Werror=implicit-function-declaration" \
        --enable-lastlog \
        --enable-man \
        --enable-maintainer-mode \