[pa_ppx.dock] Crash on empty files: Failure: hd

[Kakadu]

➜  /tmp mkcamlp5.opt   -package   camlp5.pa_o,camlp5.pr_o,camlp5.pr_dump,camlp5.extend,camlp5.quotations,pa_ppx.dock -o pp_dump                                               4.14.1+flambda
findlib: [WARNING] Interface topdirs.cmi occurs in several directories: /media/work/.opam/4.14.1+flambda/lib/ocaml, /media/work/.opam/4.14.1+flambda/lib/ocaml/compiler-libs
➜  /tmp echo "" > a.mli                                                                                                                                                       4.14.1+flambda
➜  /tmp ./pp_dump a.mli                                                                                                                                                       4.14.1+flambda
Failure: hd



➜  /tmp opam list | grep pa_ppx                                                                                                                                               4.14.1+flambda
66:pa_ppx                  0.11           PPX Rewriters for Ocaml, written using Camlp5
➜  /tmp opam list | grep camlp5                                                                                                                                               4.14.1+flambda
11:camlp5                  8.00.05        Preprocessor-pretty-printer of OCaml
12:camlp5-buildscripts     0.01           Camlp5 Build scripts (written in OCaml)

@chetmurthy, not too critical, but FYI

[chetmurthy]

Heh, I forgot that there might be empty input-files. I should do a full pass over all the PPX rewriters and make sure that any that process full implem/interf files can handle that. I found the bug btw, and fixed it. And will push to Git now.