File buildtime.patch of Package rpm-config-SUSE

diff --git a/suse/macros b/suse/macros
index 9c5f7a9..624d996 100644
--- a/suse/macros
+++ b/suse/macros
@@ -230,6 +230,12 @@
 %cflags_profile_generate -fprofile-update=atomic -fprofile-generate
 %cflags_profile_feedback -fprofile-use
 
+# Reproducible builds
+%build_mtime_policy clamp_to_buildtime
+# alternatively rpm --eval '%{lua:print(os.getenv("XXX") or os.time())}'
+%_buildtime %{getenv:SOURCE_DATE_EPOCH_MTIME}
+%_buildhost reproducible
+
 %suse_install_update_message() \
     install -D -m 644 %1 %buildroot/var/adm/update-messages/%{name}-%{version}-%{release}-%(basename %1).txt \
 %nil