Building a Haskell project with GitHub workflows fails with libffi error only on ghc-9.2

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#1

I have a GitHub action that looks like this:

name: build and test on ubuntu
on: [push]
jobs:
  build:
    runs-on: ubuntu-24.04
    strategy:
      matrix:
        ghc: ['9.6', '9.4', '9.2']
    steps:
      - uses: actions/checkout@v4
      - uses: haskell-actions/setup@v2
        with:
          ghc-version: ${{ matrix.ghc }}
          cabal-version: '3.0.0.0' # Exact version of Cabal      - 
      - name: install hdf5
        run: sudo apt-get install -y libhdf5-dev
      - name: build and test with cabal
        run: cabal test

This works for ghc-9.6 and ghc-9.4. With ghc-9.2, however, it fails with:

dist-newstyle/build/x86_64-linux/ghc-9.2.8/hdf5-1.8.11/t/hdf5-test/build/hdf5-test/hdf5-test: error while loading shared libraries: libffi.so.7: cannot open shared object file: No such file or directory

Is there a way to solve this? And can anyone explain the error?

#2

Hey! Can you share the link to the repo?

#3

GHCup uses the following bindist:

It appears ubuntu 24 doesn’t provide libffi7 anymore: Ubuntu – Package Search Results -- libffi

I don’t see any other official bindist that is built with libffi8 for GHC 9.2.8.

That means I’d have to build it myself. Also see: Build fresh versions of old bindists · Issue #903 · haskell/ghcup-hs · GitHub

The main issues with building GHC stuff downstream at the moment is:

  • there’s no github CI to build GHC yet (my private runners are on GH, for various reasons)
  • the test suite is not run, because
    • it’s incredibly flaky
    • the test bindist is constantly broken (running the test suite in the same env that GHC was built is wrong, but that’s what GHC is currently doing on gitlab)
#4

It might be fixed.

#5

It is fixed. Thank you very much!

#6

Can you also fix it for ghc-9.0? One of my collaborators is using Debian stable, which ships with this ghc version.

#8

I think the correct fix might actually be to remove pkgconfig-depends: libffi: hs-hdf5/hdf5.cabal at 18be07afb6ea1c84fae22b98882974266559900d · picca/hs-hdf5 · GitHub

That makes it pass for me. Apparently you end up with double linkage to libffi if you specify it explicitly:

root@2ca973777cb2:~/hs-hdf5# ldd /root/hs-hdf5/dist-newstyle/build/x86_64-linux/ghc-9.2.8/hdf5-1.8.11/t/hdf5-test/build/hdf5-test/hdf5-test
	linux-vdso.so.1 (0x00007ffe12701000)
	libhdf5_serial.so.103 => /lib/x86_64-linux-gnu/libhdf5_serial.so.103 (0x00007f68e9e30000)
	libffi.so.7 => not found
	libgmp.so.10 => /lib/x86_64-linux-gnu/libgmp.so.10 (0x00007f68e9daf000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f68e9bce000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f68e9aef000)
	libcrypto.so.3 => /lib/x86_64-linux-gnu/libcrypto.so.3 (0x00007f68e966a000)
	libcurl.so.4 => /lib/x86_64-linux-gnu/libcurl.so.4 (0x00007f68e95bb000)
	libsz.so.2 => /lib/x86_64-linux-gnu/libsz.so.2 (0x00007f68e95b6000)
	libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f68e9597000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f68ea1e8000)
	[...]
	libffi.so.8 => /lib/x86_64-linux-gnu/libffi.so.8 (0x00007f68e8b4b000)

I’m not sure exactly what is going on there.

#9

Indeed! Thanks for the hint!

#10

pkgconfig-depends says “uses pkgconfig to look up the libs here, then link them.” perhaps that helps explain the issue?

#11

Why does it find the internal libffi that’s shipped with GHC and links to it although it’s not in LD_LIBRARY_PATH or anything else?

#12

ghc automatically bundles libffi and links it. see the comprehensive discussion in this haddock documentation: