https://buildd.debian.org/status/package.php?p=haskell-pipes&suite=sid

...
src/Pipes.hs:141:9: error:
    • Couldn't match type: Proxy x'0 x0 a'0 a m0 a'0
                     with: forall x' x. Proxy x' x () a m ()
      Expected: a -> Producer' a m ()
        Actual: a -> Proxy x'0 x0 a'0 a m0 a'0
    • In the expression: respond
      In an equation for ‘yield’: yield = respond
    • Relevant bindings include
        yield :: a -> Producer' a m () (bound at src/Pipes.hs:141:1)
    |
141 | yield = respond
    |         ^^^^^^^

src/Pipes.hs:186:36: error:
    • Couldn't match type: forall x'2 x2. Proxy x'2 x2 () c m2 ()
                     with: Proxy x' x c' c m c'
      Expected: c -> Proxy x' x c' c m c'
        Actual: c -> Producer' c m2 ()
    • In the second argument of ‘for’, namely ‘yield’
      In the expression: for p yield
      When checking the rewrite rule "for p yield"
    • Relevant bindings include
        p :: Proxy x' x c' c m a' (bound at src/Pipes.hs:186:26)
    |
186 |   ; "for p yield" forall p . for p yield = p
    |                                    ^^^^^

src/Pipes.hs:640:8: error:
    • Couldn't match type: Proxy x'1 x1 () a m1 ()
                     with: forall x' x. Proxy x' x () a m ()
      Expected: f a -> Producer' a m ()
        Actual: f a -> Proxy x'1 x1 () a m1 ()
    • In the expression: foldr (\ a p -> yield a >> p) (return ())
      In an equation for ‘each’:
          each = foldr (\ a p -> yield a >> p) (return ())
    • Relevant bindings include
        each :: f a -> Producer' a m () (bound at src/Pipes.hs:640:1)
    |
640 | each = F.foldr (\a p -> yield a >> p) (return ())
    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 at /usr/share/perl5/Debian/Debhelper/Buildsystem/Haskell/Recipes.pm line 107.
	Debian::Debhelper::Buildsystem::Haskell::Recipes::run_quiet("debian/hlibrary.setup", "haddock", "--builddir=dist-ghc", "--with-haddock=/usr/bin/haddock", "--with-ghc=ghc", "--verbose=2", "--html", "--hoogle", ...) called at /usr/share/perl5/Debian/Debhelper/Buildsystem/Haskell/Recipes.pm line 131
	Debian::Debhelper::Buildsystem::Haskell::Recipes::run("debian/hlibrary.setup", "haddock", "--builddir=dist-ghc", "--with-haddock=/usr/bin/haddock", "--with-ghc=ghc", "--verbose=2", "--html", "--hoogle", ...) called at /usr/share/perl5/Debian/Debhelper/Buildsystem/Haskell/Recipes.pm line 707
	Debian::Debhelper::Buildsystem::Haskell::Recipes::haddock_recipe() called at -e line 1
make: *** [/usr/share/cdbs/1/class/hlibrary.mk:153: build-ghc-stamp] Error 25

We believe that the bug you reported is fixed in the latest version of
haskell-pipes, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1014000@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Ilias Tsitsimpis <iliastsi@debian.org> (supplier of updated haskell-pipes package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Sun, 03 Jul 2022 13:27:44 +0300
Source: haskell-pipes
Architecture: source
Version: 4.3.16-1
Distribution: unstable
Urgency: medium
Maintainer: Debian Haskell Group <pkg-haskell-maintainers@lists.alioth.debian.org>
Changed-By: Ilias Tsitsimpis <iliastsi@debian.org>
Closes: 1014000
Changes:
 haskell-pipes (4.3.16-1) unstable; urgency=medium
 .
   * New upstream release (Closes: #1014000)
   * Declare compliance with Debian policy 4.6.1
Checksums-Sha1:
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 a159414532ddd247340d2dcf12128de839debc57 3736 haskell-pipes_4.3.16-1.debian.tar.xz
 d2d087d8dc689e927c6d67fbe1c1af5f599e9659 8599 haskell-pipes_4.3.16-1_amd64.buildinfo
Checksums-Sha256:
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Files:
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