result of package "shadow" not reproducible

[olafhering]

A rebuild of unchanged sources results in different binaries in the shadow package.

It looks like this is the culprit:
src/shadow/gen/gen.ml:15: let files = Sys.readdir dir |> Array.to_list in

The result of readdir() is not stable. I think the list must be sorted prior further processing.

[greedy]

I ran into this problem too and filed #8 without checking for an existing issue first. Anyway, I've actually encountered build failures relating to this when using nix and getting cached binaries built from different hosts as detailed in #8.

[ghost]

Looks like we are missing a List.sort

[ghost]

I pushed a fix to master. If you can confirm that it fully fixes the issue you are observing we'll submit a new release to the opam repo.

[olafhering]

I came up with this patch a few months ago, which fixed it for me:

--- a/src/shadow/gen/gen.ml
+++ b/src/shadow/gen/gen.ml
@@ -12,7 +12,7 @@ let () =
       failwith "bad command line arguments"
   in
 
-  let files = Sys.readdir dir |> Array.to_list in
+  let files = Sys.readdir dir |> Array.to_list |> List.sort ~cmp:String.compare in
 
   let all_exposed_modules =
     List.filter files ~f:(fun fn -> Filename.check_suffix fn ".cmi")

So yes, thanks for doing commit 5d2f886.

[ghost]

Alright, new release submitted: ocaml/opam-repository#19314