Can't build numpy cross package for armv7 due to failure compiling gfortran needed in lapack and blas dependencies

[satshabad-cr]

Describe the bug
I'd like to build the python numpy package on an x86 machine for the armv7 architecture.

numpy requires liblapack and blas, which require gfortran

I already fixed one issue which is that liblapack couldn't find the gfortran compiler (see the overlay below)

I'm trying to use the 20.03 release, latest commit.

Here's what I'm running exactly:

let overlay = self: super: {
      liblapack = super.liblapacklapack.overrideAttrs (oldAttrs: {
        cmakeFlags = oldAttrs.cmakeFlags ++
                     [
                       "-DCMAKE_Fortran_COMPILER=${self.buildPackages.gfortran}/bin/armv7l-unknown-linux-gnueabihf-gfortran"
                     ];
      }
      );
    };
    pinnedPkgs = import (builtins.fetchGit {
      name = "nixos-stable-20.03";
      url = "https://github.com/nixos/nixpkgs-channels/";
      ref = "refs/heads/nixos-20.03";
      rev = "82b5f87fcc710a99c47c5ffe441589807a8202af";
    });
    pkgs = (pinnedPkgs { overlays = [ overlay ]; }).pkgsCross.armv7l-hf-multiplatform;
in
#pkgs.lapack
pkgs.blas
#pkgs.python38.pkgs.numpy
#pkgs.python38.withPackages(ps: [ps.numpy])

To Reproduce
Steps to reproduce the behavior:

1. nix-build that_file.nix

here's the error I get

libtool: link: armv7l-unknown-linux-gnueabihf-gcc -O2 -g -I/nix/store/5nhxmvjs137aym9dpiwgl3jgmmdz6q9i-glibc-2.30-armv7l-unknown-linux-gnueabihf-dev/include -B/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib/ -idirafter /nix/store/5nhxmvjs137aym9dpiwgl3jgmmdz6q9i-glibc-2.30-armv7l-unknown-linux-gnueabihf-dev/include -idirafter /nix/store/4n9fi2r61i3q3qp09qcdfj9hvlq763jx-armv7l-unknown-linux-gnueabihf-stage-final-gcc-debug-9.2.0/lib/gcc/armv7l-unknown-linux-gnueabihf/9.2.0/include-fixed -Wl,-rpath,/nix/store/ymknlm466j74dvlsvfs8qsqmyawv9pw5-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf-lib/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-rpath -Wl,/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib    -shared  -fPIC -DPIC  .libs/alloc.o .libs/atomic.o .libs/barrier.o .libs/critical.o .libs/env.o .libs/error.o .libs/icv.o .libs/icv-device.o .libs/iter.o .libs/iter_ull.o .libs/loop.o .libs/loop_ull.o .libs/ordered.o .libs/parallel.o .libs/sections.o .libs/single.o .libs/task.o .libs/team.o .libs/work.o .libs/lock.o .libs/mutex.o .libs/proc.o .libs/sem.o .libs/bar.o .libs/ptrlock.o .libs/time.o .libs/fortran.o .libs/affinity.o .libs/target.o .libs/splay-tree.o .libs/libgomp-plugin.o .libs/oacc-parallel.o .libs/oacc-host.o .libs/oacc-init.o .libs/oacc-mem.o .libs/oacc-async.o .libs/oacc-plugin.o .libs/oacc-cuda.o .libs/priority_queue.o .libs/affinity-fmt.o .libs/teams.o   -ldl  -Wl,-rpath -Wl,/nix/store/ymknlm466j74dvlsvfs8qsqmyawv9pw5-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf-lib/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-rpath -Wl,/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -pthread -Wl,-rpath -Wl,/nix/store/ymknlm466j74dvlsvfs8qsqmyawv9pw5-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf-lib/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-rpath -Wl,/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-O1 -Wl,-rpath -Wl,/nix/store/ymknlm466j74dvlsvfs8qsqmyawv9pw5-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf-lib/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-rpath -Wl,/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,-L/nix/store/lc4nci84vnna9lqa8390669f1zyy1ghc-glibc-2.30-armv7l-unknown-linux-gnueabihf/lib -Wl,--version-script -Wl,libgomp.ver   -Wl,-soname -Wl,libgomp.so.1 -o .libs/libgomp.so.1.0.0
libtool: link: (cd ".libs" && rm -f "libgomp.so.1" && ln -s "libgomp.so.1.0.0" "libgomp.so.1")
libtool: link: (cd ".libs" && rm -f "libgomp.so" && ln -s "libgomp.so.1.0.0" "libgomp.so")
libtool: link: ar rc .libs/libgomp.a  alloc.o atomic.o barrier.o critical.o env.o error.o icv.o icv-device.o iter.o iter_ull.o loop.o loop_ull.o ordered.o parallel.o sections.o single.o task.o team.o work.o lock.o mutex.o proc.o sem.o bar.o ptrlock.o time.o fortran.o affinity.o target.o splay-tree.o libgomp-plugin.o oacc-parallel.o oacc-host.o oacc-init.o oacc-mem.o oacc-async.o oacc-plugin.o oacc-cuda.o priority_queue.o affinity-fmt.o teams.o
libtool: link: ranlib .libs/libgomp.a
libtool: link: ( cd ".libs" && rm -f "libgomp.la" && ln -s "../libgomp.la" "libgomp.la" )
make[4]: Leaving directory '/build/build/armv7l-unknown-linux-gnueabihf/libgomp'
make[3]: Leaving directory '/build/build/armv7l-unknown-linux-gnueabihf/libgomp'
make[2]: Leaving directory '/build/build/armv7l-unknown-linux-gnueabihf/libgomp'
make[1]: Leaving directory '/build/build'
make: *** [Makefile:935: all] Error 2
note: keeping build directory '/tmp/nix-build-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf.drv-0'
builder for '/nix/store/3v45xj9mpzxi04jgk03qcc31jdg56i97-gfortran-debug-9.2.0-armv7l-unknown-linux-gnueabihf.drv' failed with exit code 2
cannot build derivation '/nix/store/0pa528hxi7zpyq7a0x4zdgrjisqhnw0l-gfortran-debug-wrapper-9.2.0.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/hpshxgrpjpvkc95v0rbc94vzcinz2war-blas-3.8.0-armv7l-unknown-linux-gnueabihf.drv': 1 dependencies couldn't be built
error: build of '/nix/store/hpshxgrpjpvkc95v0rbc94vzcinz2war-blas-3.8.0-armv7l-unknown-linux-gnueabihf.drv' failed

Expected behavior
The derivation builds

Metadata
Please run nix-shell -p nix-info --run "nix-info -m" and paste the result.

copying path '/nix/store/9c9mjrmfdschylny0bhkxxd7y0m90piw-nix-info' from 'https://cache.nixos.org'...
 - system: `"x86_64-linux"`
 - host os: `Linux 4.15.0-99-generic, Ubuntu, 18.04.4 LTS (Bionic Beaver)`
 - multi-user?: `no`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.3.4`
 - channels(satshabad): `"nixpkgs-20.09pre226107.62e866e4fd6"`
 - nixpkgs: `/home/satshabad/.nix-defexpr/channels/nixpkgs`

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute: numpy liblapack blas

[satshabad-cr]

Maybe related to: #53450 ?

[matthewbauer]

I'm not getting this in NixOS. It looks like a sandboxing issue.

Can you try running this:

NixOS/nix#2636 (comment)

[satshabad-cr]

Thanks for responding!

I launched this build on NixOs using an AMI on EC2 and I get the same result as in the issue report, here are the system details:

 - system: `"aarch64-linux"`
 - host os: `Linux 5.4.41, NixOS, 20.03.1926.f45ccd9d20b (Markhor)`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.3.4`
 - channels(root): `"nixos-20.03.1926.f45ccd9d20b"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`

[swflint]

A similar issue exists on unstable when building for x86.

Traceback (most recent call last):
  File "nix_run_setup", line 8, in <module>
    exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\\r\\n', '\\n'), __file__, 'exec'))
  File "setup.py", line 540, in <module>
    setup_package()
  File "setup.py", line 536, in setup_package
    setup(**metadata)
  File "/nix/store/qb19waw8994w0jm43rsxn43b244i8a0v-python3.7-numpy-1.18.1/lib/python3.7/site-packages/numpy/distutils/core.py", line 137, in setup
    config = configuration()
  File "setup.py", line 435, in configuration
    raise NotFoundError(msg)
numpy.distutils.system_info.NotFoundError: No lapack/blas resources found.

Currently on:

• system: "x86_64-linux"
• host os: Linux 5.6.5, NixOS, 20.09pre222244.22a3bf9fb9e (Nightingale)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.3.4
• channels(root): "nixos-20.09pre222244.22a3bf9fb9e, nix1709-17.09.3269.14f9ee66e63, nix1803-18.03.133402.cb0e20d6db9, nix1809-18.09.2574.a7e559a5504, nix1903-19.03.173553.6420e2649fa, unstable"
• channels(swflint): "nix2003-20.03.1950.48723f48ab9, nixos-20.09pre226148.0f5ce2fac0c, nixos-unstable"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos