Remove -no-cpp-precomp flag from Darwin builds

GCC 9 no longer accepts this flag and trying to find out what it does do
leads to an article

"-no-cpp-precomp: the compiler flag that time forgot"

that also no longer on the Internet. And most other things are
PRs/commits from over ten years ago that remove the flag since it
is no longer needed.
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20190705114243.9481-1-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg18650.html

Signed-off-by: Gert Doering <gert@greenie.muc.de>
(cherry picked from commit 0740e079a1c094627a69b8b5959c6be56e15d9f6)

diff --git a/configure.ac b/configure.ac
index d116559b7704e2ff4e0944bac08ee97dbe54ebaa..10c3cc8809a8b812ab23484da7fbd58302a2a86e 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -327,8 +327,6 @@ case "$host" in
                AC_DEFINE([TARGET_DARWIN], [1], [Are we running on Mac OS X?])
                AC_DEFINE_UNQUOTED([TARGET_PREFIX], ["M"], [Target prefix])
                have_tap_header="yes"
-               dnl some Mac OS X tendering (we use vararg macros...)
-               CPPFLAGS="$CPPFLAGS -no-cpp-precomp"
                ac_cv_type_struct_in_pktinfo=no
                ;;
        *-mingw*)