From 2a67682dfae9262a23ece54c1aba8826eea8406a Mon Sep 17 00:00:00 2001
From: Francis Dupont <fdupont@isc.org>
Date: Fri, 16 Sep 2016 23:52:02 +0200
Subject: [PATCH] explained the (hard) way it is done

---
 configure    | 5 +++++
 configure.ac | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/configure b/configure
index 8f58b1f5..a710dd1c 100755
--- a/configure
+++ b/configure
@@ -4475,8 +4475,13 @@ BINDCONFIG=
 if test "$cross_compiling" = "yes"; then
 	BINDCONFIG="--host=$host"
 fi
+# Pass CFLAGS and co. $ac_configure_args looks like "'arg1' 'arg2' ..."
+# and as there can be a space inside an argument some magic is required.
+# This sets $1 ... $N to my_configure_args, arg1 ... argN
 eval "set my_configure_args $ac_configure_args"
+# remove my_configure_args, i.e., the guard against empty $ac_configure_args
 shift
+# iterate on arguments and copying 'arg' when it begins by an upper case
 for a
 do
 	case $a in
diff --git a/configure.ac b/configure.ac
index ca460802..ce8de1be 100644
--- a/configure.ac
+++ b/configure.ac
@@ -37,8 +37,13 @@ BINDCONFIG=
 if test "$cross_compiling" = "yes"; then
 	BINDCONFIG="--host=$host"
 fi
+# Pass CFLAGS and co. $ac_configure_args looks like "'arg1' 'arg2' ..."
+# and as there can be a space inside an argument some magic is required.
+# This sets $1 ... $N to my_configure_args, arg1 ... argN
 eval "set my_configure_args $ac_configure_args"
+# remove my_configure_args, i.e., the guard against empty $ac_configure_args
 shift
+# iterate on arguments and copying 'arg' when it begins by an upper case
 for a
 do
 	case $a in