Compilation of nocrypto fails TOPKG_CONF_DEBUGGER_SUPPORT=true

On a fresh 4.07.1 switch, TOPKG_CONF_DEBUGGER_SUPPORT=true opam install nocrypto fails as follows:

Solver failed:
  Ocamlbuild knows of no rules that apply to a target named src/nocrypto.mly. This can happen if you ask Ocamlbuild to build a target with the wrong extension (e.g. .opt instead of .native) or if the source files live in directories that have not been specified as include directories.
Backtrace:
  - Failed to build the target src/nocrypto.ml
      - Building src/nocrypto.ml:
          - Failed to build all of these:
              - Building src/nocrypto.mly
              - Building src/nocrypto.mll
pkg.ml: [ERROR] cmd ['ocamlbuild' '-use-ocamlfind' '-classic-display' '-tag' 'debug'
     '-build-dir' '_build' '-plugin-tag' 'package(ocb-stubblr)' 'opam'
     'pkg/META' 'CHANGES.md' 'LICENSE.md' 'README.md'
     'src/native/des/generic.c' 'src/native/aes/aesni.c'
     'src/native/aes/generic.c' 'src/native/hash/sha512.c'
     'src/native/hash/sha256.c' 'src/native/hash/sha1.c'
     'src/native/hash/md5.c' 'src/native/hash/stubs.c' 'src/native/misc.c'
     'src/dllnocrypto_stubs.so' 'src/libnocrypto_stubs.a' 'src/nocrypto.a'
     'src/nocrypto.cmxs' 'src/nocrypto.cmxa' 'src/nocrypto.cma'
     'src/nocrypto.ml' 'src/nocrypto.cmx' 'src/nocrypto.cmi'
     'src/nocrypto.mli' 'unix/nocrypto_unix.a' 'unix/nocrypto_unix.cmxs'
     'unix/nocrypto_unix.cmxa' 'unix/nocrypto_unix.cma'
     'unix/nocrypto_entropy_unix.ml' 'unix/nocrypto_entropy_unix.cmx'
     'unix/nocrypto_entropy_unix.cmi' 'unix/nocrypto_entropy_unix.mli'
     'lwt/nocrypto_lwt.a' 'lwt/nocrypto_lwt.cmxs' 'lwt/nocrypto_lwt.cmxa'
     'lwt/nocrypto_lwt.cma' 'lwt/nocrypto_entropy_lwt.ml'
     'lwt/nocrypto_entropy_lwt.cmx' 'lwt/nocrypto_entropy_lwt.cmi'
     'lwt/nocrypto_entropy_lwt.mli']: exited with 6

dbuenzli / topkg

Compilation of nocrypto fails TOPKG_CONF_DEBUGGER_SUPPORT=true #134