build: drop official support for Ubuntu 18.04 and macOS 10.15
Increase the minimum required version of clang on linux to 7.0 because
older versions fail to compile libstdc++'s implementation of std::variant
Change-Id: Id17d95c2869634622fc8775e085b74801a486e90
diff --git a/.jenkins b/.jenkins
index 0f40e00..92b9dae 100755
--- a/.jenkins
+++ b/.jenkins
@@ -32,6 +32,9 @@
export DISABLE_HEADERS_CHECK=yes
fi
+# https://reproducible-builds.org/docs/source-date-epoch/
+export SOURCE_DATE_EPOCH=$(git log -1 --format=%ct)
+
for file in .jenkins.d/*; do
[[ -f $file && -x $file ]] || continue