Cross comp. & callCabalProjectToNix/callStackToNix

[hamishmack]

This fixes an issue where the these IFD functions fail because they try
to build and run a cross compiled nix-tools on the build system.

It may also help if there are cross compilation issues with
setup-depends (they also access the buildPackages).

[hamishmack]

This is based on #134

[angerman]

building '/nix/store/wijjmaa1398a62rg9a62r4pbcvg3rdk8-dot-cabal-at-2019-04-30T000000Z.drv'...
--
  | Downloading the latest package list from cached
  | building '/nix/store/sbkxx3sx744phvhkbmvg7ma3izd0qk0f-plan.drv'...
  | Warning: The package list for 'cached' is 18089 days old.
  | Run 'cabal update' to get the latest list of available packages.
  | Resolving dependencies...
  | Build profile: -w ghc-8.6.4 -O1
  | In order, the following would be built (use -v for more details):
  | - base-compat-0.10.5 (lib) (requires download & build)
  | - clock-0.7.2 (lib) (requires download & build)
  | - colour-2.3.4 (lib) (requires download & build)
  | - dlist-0.8.0.6 (lib) (requires download & build)
  | - hashable-1.2.7.0 (lib) (requires download & build)
  | - integer-logarithms-1.0.3 (lib) (requires download & build)
  | - primitive-0.6.4.0 (lib) (requires download & build)
  | - random-1.1 (lib) (requires download & build)
  | - safe-0.3.17 (lib) (requires download & build)
  | - semigroups-0.18.5 (lib) (requires download & build)
  | - tagged-0.8.6 (lib) (requires download & build)
  | - th-abstraction-0.3.1.0 (lib) (requires download & build)
  | - time-locale-compat-0.1.1.5 (lib) (requires download & build)
  | - transformers-compat-0.6.4 (lib) (requires download & build)
  | - ansi-terminal-0.9 (lib) (requires download & build)
  | - unordered-containers-0.2.10.0 (lib) (requires download & build)
  | - vector-0.12.0.2 (lib) (requires download & build)
  | - scientific-0.3.6.2 (lib) (requires download & build)
  | - uuid-types-1.0.3 (lib) (requires download & build)
  | - extra-1.6.15 (lib) (requires download & build)
  | - ansi-wl-pprint-0.6.8.2 (lib) (requires download & build)
  | - attoparsec-0.13.2.2 (lib) (requires download & build)
  | - optparse-applicative-0.14.3.0 (lib) (requires download & build)
  | - aeson-1.4.3.0 (lib) (requires download & build)
  | - cabal-simple-0.1.0.0 (lib) (first run)
  | - cabal-simple-0.1.0.0 (exe:cabal-simple) (first run)
  | building '/nix/store/k28ipb6xgqrdkkwzvn14qy6j2j8splnj-plan-and-src.drv'...
  | copying path '/nix/store/xf82nnr3v80bnh8s8w630h5wv52kgm3l-stdenv-linux' from 'https://cache.nixos.org'...
  | building '/nix/store/a6bsafzwnfkvddwkcs4j8y4vsnr7vcg4-pkgs-nix.drv'...
  | unpacking sources
  | unpacking source archive /nix/store/xp9idc8igpn2b2a4nnl3rh96xy2mi0h8-callStackToNix
  | source root is callStackToNix
  | patching sources
  | configuring
  | no configure script, doing nothing
  | building
  | no Makefile, doing nothing
  | installing
  | post-installation fixup
  | shrinking RPATHs of ELF executables and libraries in /nix/store/42yn3m066nsy37bspdpmv2g0dwfv58dh-pkgs-nix
  | strip is /nix/store/0y7jmqnj48ikjh37n3dl9kqw9hnn68nq-binutils-2.31.1/bin/strip
  | patching script interpreter paths in /nix/store/42yn3m066nsy37bspdpmv2g0dwfv58dh-pkgs-nix
  | checking for references to /build/ in /nix/store/42yn3m066nsy37bspdpmv2g0dwfv58dh-pkgs-nix...
  | error: access to path '/nix/store/xp9idc8igpn2b2a4nnl3rh96xy2mi0h8-callStackToNix' is forbidden in restricted mode

so we somehow use callStackToNix, but it's missing from our inputs?

[angerman]

So you can replicate this, and I'll leave this here, because (of course I didn't know this...)

$ nix-build  -I . \
   release.nix \
   -A native.tests.callStackToNix.x86_64-darwin \ 
   --option restrict-eval true \
   --option allowed-uris "https://github.com/NixOS https://github.com/input-output-hk" \
   --show-trace

specifically note the two --option values, and the -I .. The option values are required to put this into restricted mode, and allow the necessary urls for tarballs we are fetching. The -I . is required to actually be able to load the release.nix.

[angerman]

And we are green!