setup hook of gobject-introspection in nativeBuildInputs does not run with strictDeps

[emmanuelrosa]

Issue description

virt-manager fails to load and instead produces the error "Namespace LibvirtGLib not available"

Traceback (most recent call last):
  File "/nix/store/b8na689bifds8z2xg1bragbw54mznppa-virt-manager-2.1.0/share/virt-manager/virt-manager", line 17, in <module>                                                                   
    gi.require_version('LibvirtGLib', '1.0')
  File "/nix/store/kiw47xswi1041sbvbgrlfy0xs0zlwyvk-python3.7-pygobject-3.30.4/lib/python3.7/site-packages/gi/__init__.py", line 129, in require_version                                        
    raise ValueError('Namespace %s not available' % namespace)
ValueError: Namespace LibvirtGLib not available

I'm aware of #33754 and #34000. I have the changes in the merged commit. Yet, I receive the error.

Steps to reproduce

1. Install virt-manager
2. Open a terminal and run virt-manager

Technical details

• system: "x86_64-linux"
• host os: Linux 4.14.104, NixOS, 19.09.git.27cb066 (Loris)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.2
• channels(root): "nixos-19.09pre171582.26d8a8c0eb2"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

NOTE: My nixpkgs is not as shown above but rather a clone of this repo at commit 27cb066

[jtojnar]

I think this is another issue caused strictDeps being enabled for Python packages (#54182); I also noticed it in #56783 (comment).

strictDeps probably prevents the setup hook in nativeBuildInputs from running; though, I would expect hostOffset to work:

nixpkgs/pkgs/development/libraries/gobject-introspection/setup-hook.sh

Line 13 in 51174e7

addEnvHooks "$hostOffset" make_gobject_introspection_find_gir_files

We will need to fix the setup hook? cc @Ericson2314 @hedning

[Ericson2314]

gobject-introspection is a terrible thing that makes cross compilation impossible. Try adding it as both as a buildInput and nativeBuildInput to get native builds working.

CC @eternaleye

[jtojnar]

Is there nothing else we can do to make addEnvHooks "$hostOffset" work with the setup hook?

[jtojnar]

It is even more serious

with import <nixpkgs> {};
stdenv.mkDerivation {
  name = "setup-hook-test";
  unpackPhase = ":";
  dontBuild = true;
  nativeBuildInputs = [ wrapGAppsHook ];
  installPhase = ''
    runHook preInstall
    mkdir -p $out/bin
    touch $out/bin/test
    chmod +x $out/bin/test
    runHook postInstall
  '';
}

does not even pick up the librsvg dependency

nixpkgs/pkgs/top-level/all-packages.nix

Lines 394 to 396 in 4a48f6a

	wrapGAppsHook = makeSetupHook {
	deps = lib.optional (!stdenv.isDarwin) gnome3.dconf.lib ++ [ gtk3 librsvg makeWrapper ];
	} ../build-support/setup-hooks/wrap-gapps-hook.sh;

for GDK_PIXBUF_MODULE_FILE. Curiously, it detects dconf; and multiple times at that:

#! /nix/store/cinw572b38aln37glr0zb8lxwrgaffl4-bash-4.4-p23/bin/bash -e
export GIO_EXTRA_MODULES='/nix/store/h9wqk3nx4h020xrvha2si7y01alk337w-dconf-0.30.1-lib/lib/gio/modules'${GIO_EXTRA_MODULES:+':'}$GIO_EXTRA_MODULES
export GIO_EXTRA_MODULES='/nix/store/h9wqk3nx4h020xrvha2si7y01alk337w-dconf-0.30.1-lib/lib/gio/modules'${GIO_EXTRA_MODULES:+':'}$GIO_EXTRA_MODULES
exec -a "$0" "/nix/store/16khixg577v3f2bdfs30mhj6n8l6hsq2-setup-hook-test/bin/.test-wrapped"  "${extraFlagsArray[@]}" "$@"

are setup hooks not propagated any more? If I add gdk-pixbuf, librsvg will suddenly be picked up:

with import <nixpkgs> {};
stdenv.mkDerivation {
  name = "setup-hook-test";
  unpackPhase = ":";
  dontBuild = true;
  buildInputs = [ ];
  nativeBuildInputs = [ wrapGAppsHook gdk_pixbuf ];
  installPhase = ''
    runHook preInstall
    mkdir -p $out/bin
    touch $out/bin/test
    chmod +x $out/bin/test
    runHook postInstall
  '';
}

#! /nix/store/cinw572b38aln37glr0zb8lxwrgaffl4-bash-4.4-p23/bin/bash -e
export GIO_EXTRA_MODULES='/nix/store/h9wqk3nx4h020xrvha2si7y01alk337w-dconf-0.30.1-lib/lib/gio/modules'${GIO_EXTRA_MODULES:+':'}$GIO_EXTRA_MODULES
export GIO_EXTRA_MODULES='/nix/store/h9wqk3nx4h020xrvha2si7y01alk337w-dconf-0.30.1-lib/lib/gio/modules'${GIO_EXTRA_MODULES:+':'}$GIO_EXTRA_MODULES
export GDK_PIXBUF_MODULE_FILE='/nix/store/w073vf5lhf08n1pg77qsinq5qqdaymqy-librsvg-2.44.12/lib/gdk-pixbuf-2.0/2.10.0/loaders.cache'
export XDG_DATA_DIRS='/nix/store/ialw7015yr8wm578d4j09fi3ay5hk96c-gtk+3-3.24.5/share/gsettings-schemas/gtk+3-3.24.5:/nix/store/ialw7015yr8wm578d4j09fi3ay5hk96c-gtk+3-3.24.5/share/gsettings-schemas/gtk+3-3.24.5:/nix/store/ialw7015yr8wm578d4j09fi3ay5hk96c-gtk+3-3.24.5/share/gsettings-schemas/gtk+3-3.24.5'${XDG_DATA_DIRS:+':'}$XDG_DATA_DIRS
exec -a "$0" "/nix/store/pfk5qj7gnhjzkmklyns7svdmqqc8afkh-setup-hook-test/bin/.test-wrapped"  "${extraFlagsArray[@]}" "$@"

But I guess since librsvg is propagated by the hook in nativeBuildInputs it will be the native version. We would need to propagate it to offset -1. All this bash magic makes my head tumble.

[FRidh]

As a last resort strictDeps could be disabled for this expression.

[jtojnar]

Still need to fix the underlying issue.

[Ericson2314]

Listing twice is not a hack in my mind. It is the proper way to indicate that a dependency is both a build and run time dependency.

[Ericson2314]

For that second issue, I don't remember setup hooks being automatically propagated ever, but a setup can propagate a dependency that it will itself pick up.

[jtojnar]

Well, in my mind, it is not a run time dependency (at least not a direct one). Most of the time, it is only used during build for the setup hook.

[jtojnar]

After discussion on IRC we have decided to move make_gobject_introspection_find_gir_files and giDiscoverSelf into a separated setup hook and to add make_gobject_introspection_find_gir_files to $targetOffset.

[Artturin]

Fixed by 71cbf3b

gobject-introspection has to in nativeBuildInputs for the hook to work properly

if a typelib from gobject-introspection is needed then gobject-introspection has to be added to buildInputs (until #189215 is in master)

$ pwd
/nix/store/j68vcd82l5xx76jqida4zqk0nw55b6cm-gobject-introspection-1.72.0/lib/girepository-1.0
$ \ls
cairo-1.0.typelib  DBusGLib-1.0.typelib    freetype2-2.0.typelib  GIRepository-2.0.typelib  GLib-2.0.typelib	GObject-2.0.typelib  Vulkan-1.0.typelib  xfixes-4.0.typelib  xlib-2.0.typelib
DBus-1.0.typelib   fontconfig-2.0.typelib  Gio-2.0.typelib	 GL-1.0.typelib	   GModule-2.0.typelib  libxml2-2.0.typelib  win32-1.0.typelib   xft-2.0.typelib     xrandr-1.3.typelib