patch 8.2.0910: Vim is not reproducibly buildable
Problem: Vim is not reproducibly buildable.
Solution: Use the $SOURCE_DATE_EPOCH environment variable in configure.
(James McCoy, closes #513) Give a warning about using it.
diff --git a/src/config.h.in b/src/config.h.in
index 5c8c7e5..7055b6f 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -30,6 +30,9 @@
/* Define when __DATE__ " " __TIME__ can be used */
#undef HAVE_DATE_TIME
+/* Defined from $SOURCE_DATE_EPOCH, used as the build date */
+#undef BUILD_DATE
+
/* Define when __attribute__((unused)) can be used */
#undef HAVE_ATTRIBUTE_UNUSED