On Sat, Mar 17 2018, Nguyễn Thái Ngọc Duy jotted:

Because of struct packing from now on we can only handle max depth
4095
[...]
+	if (depth >= (1 << OE_DEPTH_BITS))
+		die(_("delta chain depth %d is greater than maximum limit %d"),
+		    depth, (1 << OE_DEPTH_BITS));
+

This has a off-by-one error:

    $ git repack --depth=4096
    fatal: delta chain depth 4096 is greater than maximum limit 4096

Per the check we should be feeding `(1 << OE_DEPTH_BITS) - 1` to die().