From 349be05ee5cbfd680955d19a9ec2df72966399b4 Mon Sep 17 00:00:00 2001
From: "Bernhard M. Wiedemann" <bwiedemann@suse.de>
Date: Fri, 21 Jul 2017 15:18:40 +0200
Subject: Allow to override build date

in order to make builds reproducible.
See https://reproducible-builds.org/ for why this is good
and https://reproducible-builds.org/specs/source-date-epoch/
for the definition of this variable.

This date call is designed to work with both GNU date and BSD date.

diff --git a/configure.ac b/configure.ac
index 4f7d3d3..010c2e0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -424,9 +424,13 @@ AC_SEARCH_LIBS(
 # Lastly, take care of crosstool-NG internal values
 #--------------------------------------------------------------------
 # Hey! We need the date! :-)
-AC_SUBST(
-    [DATE],
-    [$(date +%Y%m%d)])
+DATE_FMT="%Y%m%d"
+if test "x$SOURCE_DATE_EPOCH" = "x"; then
+    DATE=$(date "+$DATE_FMT")
+else
+    DATE="$(date -u -d "@$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || date -u -r "$SOURCE_DATE_EPOCH" "+$DATE_FMT" 2>/dev/null || date -u "+$DATE_FMT")"
+fi
+AC_SUBST([DATE])
 
 # Decorate the version string if needed
 AS_IF(
-- 
cgit v0.10.2-6-g49f6