Build fails with "Path.Local.parent called on the root"

[rnml]

After I got the most basic hello world program running from the quick start guide, I then tried to build a program that depends on Core. It failed with the error message mentioned in the issue title.

More concretely, this bash snippet

set -x
cat hello_world.ml
cat jbuild
cat jbuild-workspace
jbuilder build hello_world.exe || echo FAILED
cat _build/log

yields

+ cat hello_world.ml
open Core.Std

let command =
  let open Command.Let_syntax in
  Command.basic' ~summary:"say hello to the world"
    [%map_open
     let () = return ()
     in
     fun () ->
       print_endline "Hello, world!"
    ]
+ cat jbuild
;; -*- mode: lisp -*-

(jbuild_version 1)

(executables
 ((names (hello_world))
  (libraries (core))))
+ cat jbuild-workspace
;; -*- mode: lisp -*-
(context (
 (switch system)
 (merlin false)
))
+ jbuilder build hello_world.exe
Workspace root: /home/nathan/pill/src/hello-world
Running[0]: /usr/local/bin/opam config var root > /tmp/jbuild1cabf7.output
Running[1]: /usr/local/bin/opam config env --root /home/nathan/.opam --switch system --sexp > /tmp/jbuildb8308b.output
Running[2]: /usr/bin/ocamlc -config > /tmp/jbuild733b0a.output
Running[3]: /usr/bin/ocamlfind printconf path > /tmp/jbuildaf51b3.output
Running[4]: /usr/local/bin/opam config var lib > /tmp/jbuild796e42.output
Actual targets:
- _build/system/hello_world.exe
Internal error, please report upstream including the contents of _build/log.
Description: Path.Local.parent called on the root
Backtrace:
Raised at file "src/import.ml", line 20, characters 43-65
Called from file "src/lib_db.ml", line 19, characters 43-60
Called from file "src/lib_db.ml", line 19, characters 16-60
Called from file "src/lib_db.ml", line 19, characters 16-60
Called from file "src/lib_db.ml" (inlined), line 24, characters 14-45
Called from file "src/lib_db.ml", line 28, characters 8-42
Called from file "src/lib_db.ml", line 123, characters 43-68
Called from file "src/build_system.ml", line 201, characters 8-16
Called from file "src/build_system.ml", line 214, characters 16-24
Called from file "src/build_system.ml", line 201, characters 8-16
Called from file "src/build_system.ml", line 201, characters 8-16
Called from file "src/build_system.ml", line 231, characters 17-38
Called from file "src/build_system.ml", line 314, characters 27-53
Called from file "src/future.ml", line 93, characters 8-12
+ echo FAILED
FAILED
+ cat _build/log
# jbuilder build hello_world.exe
$ /usr/local/bin/opam config var root > /tmp/jbuild1cabf7.output
$ /usr/local/bin/opam config env --root /home/nathan/.opam --switch system --sexp > /tmp/jbuildb8308b.output
$ /usr/bin/ocamlfind printconf path > /tmp/jbuildaf51b3.output
$ /usr/local/bin/opam config var lib > /tmp/jbuild796e42.output
$ /usr/bin/ocamlc -config > /tmp/jbuild733b0a.output
# Jbuilder context:
#  ((name system)
#   (kind ((root /home/nathan/.opam) (switch system)))
#   (merlin false)
#   (for_host ())
#   (build_dir _build/system)
#   (toplevel_path (/home/nathan/.opam/system/lib/toplevel))
#   (ocaml_bin /usr/bin)
#   (ocaml /usr/bin/ocaml)
#   (ocamlc /usr/bin/ocamlc)
#   (ocamlopt (/usr/bin/ocamlopt))
#   (ocamldep /usr/bin/ocamldep)
#   (ocamllex /usr/bin/ocamllex)
#   (ocamlyacc /usr/bin/ocamlyacc)
#   (ocamlmklib /usr/bin/ocamlmklib)
#   (env
#    ((CAML_LD_LIBRARY_PATH
#      /home/nathan/.opam/system/lib/stublibs:/usr/lib/ocaml/stublibs)
#     (MANPATH :/home/nathan/.opam/system/man)
#     (OCAML_TOPLEVEL_PATH /home/nathan/.opam/system/lib/toplevel)
#     (OPAMSWITCH system)
#     (PATH
#      /home/nathan/.opam/system/bin:/home/nathan/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin)
#     (PERL5LIB /home/nathan/.opam/system/lib/perl5)))
#   (findlib_path
#    (/usr/lib/ocaml/METAS
#     /usr/lib/ocaml
#     /usr/local/lib/ocaml/4.02.3
#     /home/nathan/.opam/system/lib))
#   (arch_sixtyfour true)
#   (natdynlink_supported true)
#   (opam_vars ((lib /home/nathan/.opam/system/lib) (root /home/nathan/.opam)))
#   (ocamlc_config
#    ((architecture amd64)
#     (asm as)
#     (asm_cfi_supported true)
#     (ast_impl_magic_number Caml1999M016)
#     (ast_intf_magic_number Caml1999N015)
#     (bytecomp_c_compiler
#      "gcc -O  -D_FILE_OFFSET_BITS=64 -D_REENTRANT -O -fPIC")
#     (bytecomp_c_libraries "-lm  -ldl -lcurses -lpthread")
#     (cc_profile -pg)
#     (ccomp_type cc)
#     (cma_magic_number Caml1999A011)
#     (cmi_magic_number Caml1999I017)
#     (cmo_magic_number Caml1999O010)
#     (cmt_magic_number Caml2012T004)
#     (cmx_magic_number Caml1999Y014)
#     (cmxa_magic_number Caml1999Z013)
#     (cmxs_magic_number Caml2007D002)
#     (default_executable_name a.out)
#     (exec_magic_number Caml1999X011)
#     (ext_asm .s)
#     (ext_dll .so)
#     (ext_lib .a)
#     (ext_obj .o)
#     (host x86_64-pc-linux-gnu)
#     (model default)
#     (native_c_compiler "gcc -O  -D_FILE_OFFSET_BITS=64 -D_REENTRANT")
#     (native_c_libraries "-lm  -ldl")
#     (native_pack_linker "ld -r --hash-style=both --as-needed --build-id -o ")
#     (os_type Unix)
#     (ranlib ranlib)
#     (standard_library /usr/lib/ocaml)
#     (standard_library_default /usr/lib/ocaml)
#     (standard_runtime /usr/bin/ocamlrun)
#     (system linux)
#     (systhread_supported true)
#     (target x86_64-pc-linux-gnu)
#     (version 4.02.3)
#     (with_frame_pointers false)))
#   (which ((ocamlc (/usr/bin/ocamlc)) (ocamlfind (/usr/bin/ocamlfind)))))

[bmillwood]

Same symptoms as #15 -- are you using a jbuilder that includes the fix for that?

[ghost]

1.0+beta3 was released yesterday and includes the fix for #15 BTW

[rnml]

Sweet, this worked for me. Thank you.

[rnml]

Ok, so getting farther. How does one use ppx_jane? I couldn't seem to get that to work with a preprocess entry in my jbuild file like the manual says.

…

On Thu, Mar 16, 2017 at 03:38 Jérémie Dimino ***@***.***> wrote: 1.0+beta3 was released yesterday and includes the fix for #15 <#15> BTW — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#28 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABGYaWNGpUmekQRMU-27YiQJ3GvM0y7mks5rmObogaJpZM4MeW9H> .

[ghost]

With the development version of JS packages (stable release coming soon), (preprocess (pps (ppx_jane))) should just work. In the meantime, this should work: (preprocess (ppx (ppx_jane ppx_driver.runner)))