References: <20161216163218.25449-1-jm@...1926...>
From: Julien Muchembled <jm@...1926...>
Message-ID: <34dd18d1-a2fb-7e89-7a19-43603f0491ba@...1926...>
Date: Fri, 16 Dec 2016 17:42:30 +0100
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In-Reply-To: <20161216163218.25449-1-jm@...1926...>
Subject: [Openvpn-devel] What about adding -Werror=implicit -Werror=format
 -Werror=format-security ?
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To: openvpn-devel@lists.sourceforge.net
Cc: kirr@...1926...

To avoid issues like https://community.openvpn.net/openvpn/ticket/792 to happen again, I wanted to also submit a patch that adds a few -Werror= flags. However, I wonder what would be your preferred way to only add flags that are supported by the compiler.

One solution is with
  https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
which means:
- copy ax_check_compile_flag.m4 from the autoconf archive to the openvpn repository
- include it in configure.ac
- and for example:

AX_CHECK_COMPILE_FLAG([ -Werror=implicit ], [
    CFLAGS_EXTRA="$CFLAGS_EXTRA -Werror=implicit"
])

Julien