From 02682e509389a6de23a2614da3b43abebf45a4f2 Mon Sep 17 00:00:00 2001
From: Patrick Mahoney <pat@polycrystal.org>
Date: Sat, 22 Apr 2017 13:33:09 -0500
Subject: [PATCH 1/3] ocamlPackages.ocaml_lwt: use buildOcaml

This adds the shared objects setup hook to prepare
CAML_LD_LIBRARY_PATH.
---
 pkgs/development/ocaml-modules/lwt/default.nix | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/ocaml-modules/lwt/default.nix b/pkgs/development/ocaml-modules/lwt/default.nix
index 53d5a25a39eb..d450a877517e 100644
--- a/pkgs/development/ocaml-modules/lwt/default.nix
+++ b/pkgs/development/ocaml-modules/lwt/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchzip, which, cryptopp, ocaml, findlib, ocamlbuild, camlp4
+{ stdenv, buildOcaml, fetchzip, which, cryptopp, ocaml, findlib, ocamlbuild, camlp4
 , ocaml_react, ocaml_ssl, libev, pkgconfig, ncurses, ocaml_oasis, glib
 , ppx_tools, result, cppo
 , ppxSupport ? stdenv.lib.versionAtLeast ocaml.version "4.02"
@@ -15,8 +15,8 @@ let param =
   };
 in
 
-stdenv.mkDerivation rec {
-  name = "ocaml-lwt-${version}";
+buildOcaml rec {
+  name = "lwt";
   inherit (param) version;
 
   src = fetchzip {
@@ -36,6 +36,8 @@ stdenv.mkDerivation rec {
 
   createFindlibDestdir = true;
 
+  hasSharedObjects = true;
+
   meta = with stdenv.lib; {
     homepage = http://ocsigen.org/lwt;
     description = "Lightweight thread library for Objective Caml";

From d27e250627dd2f03e1436410c69b49f6463874ca Mon Sep 17 00:00:00 2001
From: Patrick Mahoney <pat@polycrystal.org>
Date: Sat, 22 Apr 2017 13:36:23 -0500
Subject: [PATCH 2/3] ocamlPackages.lambdaTerm: use buildOcaml

This adds the shared objects setup hook to prepare
CAML_LD_LIBRARY_PATH.
---
 pkgs/development/ocaml-modules/lambda-term/default.nix | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/ocaml-modules/lambda-term/default.nix b/pkgs/development/ocaml-modules/lambda-term/default.nix
index f66773d426af..86e4ebccbae6 100644
--- a/pkgs/development/ocaml-modules/lambda-term/default.nix
+++ b/pkgs/development/ocaml-modules/lambda-term/default.nix
@@ -1,10 +1,10 @@
-{ stdenv, fetchurl, libev, ocaml, findlib, ocamlbuild, ocaml_lwt, ocaml_react, zed }:
+{ stdenv, buildOcaml, fetchurl, libev, ocaml, findlib, ocamlbuild, ocaml_lwt, ocaml_react, zed }:
 
 assert stdenv.lib.versionAtLeast (stdenv.lib.getVersion ocaml) "4.01";
 
-stdenv.mkDerivation rec {
+buildOcaml rec {
   version = "1.10";
-  name = "lambda-term-${version}";
+  name = "lambda-term";
 
   src = fetchurl {
     url = "https://github.com/diml/lambda-term/archive/${version}.tar.gz";
@@ -17,6 +17,8 @@ stdenv.mkDerivation rec {
 
   createFindlibDestdir = true;
 
+  hasSharedObjects = true;
+
   meta = { description = "Terminal manipulation library for OCaml";
     longDescription = ''
     Lambda-term is a cross-platform library for

From 1a7586ce24598c03c2ab823e74e5e2413b450cdf Mon Sep 17 00:00:00 2001
From: Patrick Mahoney <pat@polycrystal.org>
Date: Sat, 22 Apr 2017 14:01:05 -0500
Subject: [PATCH 3/3] ocamlPackages.utop: fix environment variables

In the wrapper scripts, both OCAMLPATH and CAML_LD_LIBRARY_PATH where
being created with a trailing literal $OCAMLPATH, rather than the
expanded version. Thus if, for example, ocamlPackages.core was present
in OCAMLPATH prior to running utop, the wrapper script would set the
variable to $utop_dependencies:'$OCAMLPATH', and when using utop to
open Core.Std, the following error was reported:

    findlib: [WARNING] cannot read directory $OCAMLPATH: No such file
    or directory

This patch fixes the quoting issue, and further refactors the build to
use standard wrapProgram helper, and uses an "inner derivation" to
re-use the setupHook machinery of buildOCaml and findlib instead of
manually specifying the OCAMLPATH required for utop along with
transitive dependencies.
---
 pkgs/development/tools/ocaml/utop/default.nix | 44 +++++++++++++------
 1 file changed, 31 insertions(+), 13 deletions(-)

diff --git a/pkgs/development/tools/ocaml/utop/default.nix b/pkgs/development/tools/ocaml/utop/default.nix
index 31549729cfe7..bec72939fa07 100644
--- a/pkgs/development/tools/ocaml/utop/default.nix
+++ b/pkgs/development/tools/ocaml/utop/default.nix
@@ -28,21 +28,39 @@ stdenv.mkDerivation rec {
   dontStrip = true;
 
   postFixup =
-   let p = p: "${p}/lib/ocaml/${ocaml.version}/site-lib"; in
-   ''
-   pushd $out/bin
-   for prog in *
+   let
+     path = "etc/utop/env";
+
+     # derivation of just runtime deps so env vars created by
+     # setup-hooks can be saved for use at runtime
+     runtime = stdenv.mkDerivation rec {
+       name = "utop-runtime-env-${version}";
+
+       buildInputs = [ findlib ] ++ propagatedBuildInputs;
+
+       phases = [ "installPhase" ];
+
+       installPhase = ''
+         mkdir -p "$out"/${path}
+         for e in OCAMLPATH CAML_LD_LIBRARY_PATH; do
+           printf %s "''${!e}" > "$out"/${path}/$e
+         done
+       '';
+     };
+
+     get = key: ''$(cat "${runtime}/${path}/${key}")'';
+   in ''
+   for prog in "$out"/bin/*
    do
-    mv $prog .$prog-wrapped
-    cat > $prog <<EOF
-#!/bin/sh
-export CAML_LD_LIBRARY_PATH=${p ocaml_lwt}/lwt:${p lambdaTerm}/lambda-term:'\$CAML_LD_LIBRARY_PATH'
-export OCAMLPATH=${p ocaml_lwt}:${p ocaml_react}:${p camomile}:${p zed}:${p lambdaTerm}:"$out"/lib/ocaml/${ocaml.version}/site-lib:'\$OCAMLPATH'
-${ocaml}/bin/ocamlrun $out/bin/.$prog-wrapped \$*
-EOF
-    chmod +x $prog
+    # Note: wrapProgram by default calls 'exec -a $0 ...', but this
+    # breaks utop on Linux with OCaml 4.04, and is disabled with
+    # '--argv0 ""' flag. See https://github.com/NixOS/nixpkgs/issues/24496
+    wrapProgram $prog \
+      --argv0 "" \
+      --prefix CAML_LD_LIBRARY_PATH ":" "${get "CAML_LD_LIBRARY_PATH"}" \
+      --prefix OCAMLPATH ":" "${get "OCAMLPATH"}" \
+      --prefix OCAMLPATH ":" $(unset OCAMLPATH; addOCamlPath "$out"; printf %s "$OCAMLPATH")
    done
-   popd
    '';
 
   meta = {