File reproducible.patch of Package armagetron

From bfdf023b82aafa258580251f4869784eb86f5f6e Mon Sep 17 00:00:00 2001
From: "Bernhard M. Wiedemann" <bwiedemann@suse.de>
Date: Sat, 20 Apr 2024 08:00:54 +0200
Subject: [PATCH] Allow to override build date with SOURCE_DATE_EPOCH

to make release 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.

The previous code was added in commit b940783d0a38246fbf7326e9ccf625fd185c062f
by Manuel Moos (@zmanuel)
but only helped when running bootstrap.sh with a .git dir.
However, release tarballs don't have a .git dir.

This patch was done while working on reproducible builds for openSUSE.

diff --git a/configure.ac b/configure.ac
index acf8568e4..70e53c6c6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -47,7 +47,7 @@ version=$VERSION
 AC_SUBST(version)
 
 source_date_epoch=SOURCE_DATE_EPOCH
-test ${source_date_epoch} = SOURCE_DATE_EPOCH && source_date_epoch=`date +%s`
+test ${source_date_epoch} = SOURCE_DATE_EPOCH && source_date_epoch=${SOURCE_DATE_EPOCH:-`date +%s`}
 AC_SUBST(source_date_epoch)
 
 # determine date, following the epoch time if we can