From 99d770f3a43ce44659d6dd81caf93040721cc628 Mon Sep 17 00:00:00 2001
From: Michael Forney <mforney@mforney.org>
Date: Sun, 22 Apr 2018 23:46:33 -0700
Subject: [PATCH] configure: Use awk to implement unique()

Otherwise, if printf is not a builtin it runs very very slowly.
---
 configure | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/configure b/configure
index dee507cb6a..9b7ddfee24 100755
--- a/configure
+++ b/configure
@@ -838,10 +838,7 @@ prepend(){
 
 unique(){
     var=$1
-    uniq_list=""
-    for tok in $(eval echo \$$var); do
-        uniq_list="$(filter_out $tok $uniq_list) $tok"
-    done
+    uniq_list=$(eval "printf '%s\n' \$$var" | awk '!($0 in seen) { seen[$0] = 1; printf "%s ", $0 }')
     eval "$var=\"${uniq_list}\""
 }
 
-- 
2.17.0