GHC 8.4.1-alpha3 regression: Build error when `build-type: Custom` and `license: OtherLicense` are in the .cabal file

I got an error installing Agda upstream. I could reduce the error when build-type: Custom and license: OtherLicense are in the .cabal file:

Foo.cabal:

name:                Foo
version:             0.1.0.0
license:             OtherLicense
build-type:          Custom
cabal-version:       >=1.10

library
  exposed-modules:     Foo
  build-depends:       base
  default-language:    Haskell2010

Foo.hs:

module Foo where

foo :: Int -> Int
foo n = n

Setup.hs:

import Distribution.Simple
main = defaultMain

The error:

$ cabal install
Failed to install Foo-0.1.0.0
cabal: Error: some packages failed to install:
Foo-0.1.0.0-33ReQaKfqaD7MoDL7J5kFM failed during the final install step. The
exception was:
dieVerbatim: user error (cabal: Couldn't parse the output of 'setup register
--gen-pkg-config':NoParse
"license" 5
)

cabal-install version:

$ cabal --version
cabal-install version 2.0.0.1
compiled using version 2.0.1.0 of the Cabal library

If I change the license field or the build field, the error disappeared. I didn't get the above error using GHC 8.4.1-alpha2.

changed weight to 5

added Tbug Trac import labels

TL;DR, I don't think this a valid issue. To fix, use up-to-data cabal-install. We have to work on the error reporting though, as I mention below

---

The failure is caused by unfortunately late (it missed by a few hours alpha2) change to Cabal, which affects how ghc-pkg stores licence field. It will be stored as SPDX expression in Cabal-2.2 / GHC-8.4

% ghc-pkg-8.4.1 dump | grep license | sort -u
license: BSD-2-Clause
license: BSD-3-Clause

Side note: As e.g. Agda is currently OtherLicense, please consider bumping to cabal-version: 2.2 and using MIT AND BSD-3-Clause instead of opaque OtherLicense. That's one of motivation of using SPDX license expressions starting from cabal spec 2.2.

---

There are two things wrong with the premise:

• There aren't custom-setup & setup-depends. This causes cabal-install to apply implicit Cabal < 2 bound. Then Setup.hs is built against Cabal-1.24 which cannot know about GHC-8.4. We will fix that buy making old Cabal non-compilable against base-4.11. It's semantically incorrect (as they compile fine, they just don't know about GHC-8.4).

• It was an oversight to allow Cabal-1.24 to work with GHC-8.2. But that ship has sailed.

• Similarly, as cabal-install-2.0 uses Cabal-2.0 (as version shows), that old Cabal lib version isn't compatible with GHC-8.4

• It's on the task list to make Cabal (and thus cabal-install) to refuse to work with GHCs it doesn't know about. We cannot predict the future.

To illustrate, I try a dry build with package as reported:

% /opt/cabal/2.0/bin/cabal new-build  --dry                                  
Resolving dependencies...
In order, the following would be built (use -v for more details):
 - Foo-0.1.0.0 (lib:Foo) (first run)

% cabal-plan topo                         
Foo-0.1.0.0 lib setup
transformers-0.5.2.0
template-haskell-2.12.0.0
ghc-boot-th-8.2.2
old-time-1.1.0.3
old-locale-1.0.0.7
Cabal-1.24.2.0 <-- !!!
process-1.4.3.0
pretty-1.1.3.3
directory-1.3.0.2
unix-2.7.2.2
time-1.8.0.2
filepath-1.4.1.2
binary-0.8.5.1
containers-0.5.10.2
bytestring-0.10.8.2
deepseq-1.4.3.0
array-0.5.2.0
base-4.10.1.0
integer-gmp-1.0.1.0
ghc-prim-0.5.1.1
rts-1.0

Note: Cabal-1.24.2.0 is built!

If I actually try to build with GHC-8.4.1 alpha, I have to allow-newer

% /opt/cabal/2.0/bin/cabal new-build -w ghc-8.4.1 --allow-newer='Cabal' --dry
Resolving dependencies...
In order, the following would be built (use -v for more details):
 - old-time-1.1.0.3 (lib) (requires build)
 - Foo-0.1.0.0 (lib:Foo) (first run)

% cabal-plan topo
Foo-0.1.0.0 lib setup
template-haskell-2.13.0.0
ghc-boot-th-8.4.0.20180204
old-time-1.1.0.3
old-locale-1.0.0.7
Cabal-2.1.0.0
process-1.6.3.0
pretty-1.1.3.6
parsec-3.1.12
text-1.2.3.0
mtl-2.2.2
transformers-0.5.5.0
directory-1.3.1.5
unix-2.7.2.2
time-1.8.0.2
filepath-1.4.2
binary-0.8.5.1
containers-0.5.11.0
bytestring-0.10.8.2
deepseq-1.4.3.0
array-0.5.2.0
base-4.11.0.0
integer-gmp-1.0.1.0
ghc-prim-0.5.2.0
rts-1.0

But still, there's old Cabal in cabal-install-2.0 so build will fail, as reported. With new-build a bit differently:

% /opt/cabal/2.0/bin/cabal new-build -w ghc-8.4.1 --allow-newer='Cabal'      

Resolving dependencies...
In order, the following will be built (use -v for more details):
 - old-time-1.1.0.3 (lib) (requires build)
 - Foo-0.1.0.0 (lib:Foo) (first run)
Configuring old-time-1.1.0.3 (lib)...

Failed to build old-time-1.1.0.3. The failure occurred during the configure
step.
Build log (
/home/ogre/.cabal/logs/ghc-8.4.0.20180204/old-time-1.1.0.3-327228ceac90b6d4a229ac30aefee4aa0a193769fd1eeeece7e4a5f18f88fe98.log
):
Configuring library for old-time-1.1.0.3..
cabal: failed to parse output of 'ghc-pkg dump'
cabal: Failed to build old-time-1.1.0.3 (which is required by Foo-0.1.0.0).
See the build log above for details.

However if we use cabal-install-head (which will become 2.2 soon-ish):

% /opt/cabal/head/bin/cabal new-build -w ghc-8.4.1 --allow-newer='Cabal'

is ok.

Also if we add proper custom-setup we won't need --allow-newer:

% git diff
diff --git a/Foo.cabal b/Foo.cabal
index e4fb0c2..587ccd4 100644
--- a/Foo.cabal
+++ b/Foo.cabal
@@ -4,6 +4,9 @@ license:             OtherLicense
 build-type:          Custom
 cabal-version:       >=1.10
 
+custom-setup
+  setup-depends: Cabal >= 1.10 && <2.3, base
+
 library
   exposed-modules:     Foo
   build-depends:       base

% /opt/cabal/head/bin/cabal new-build -w ghc-8.4.1
Build profile: -w ghc-8.4.0.20180204 -O1
In order, the following will be built (use -v for more details):
 - Foo-0.1.0.0 (lib:Foo) (first run)
Preprocessing library for Foo-0.1.0.0..
Building library for Foo-0.1.0.0..

And finally, using sandboxes and cabal-install-head build works too:

% /opt/cabal/head/bin/cabal sandbox init
Writing a default package environment file to
/home/ogre/mess/issue-14475/cabal.sandbox.config
Creating a new sandbox at /home/ogre/mess/issue-14475/.cabal-sandbox

% /opt/cabal/head/bin/cabal install
Resolving dependencies...
Notice: installing into a sandbox located at
/home/ogre/mess/issue-14475/.cabal-sandbox
Configuring Foo-0.1.0.0...
Building Foo-0.1.0.0...
Installed Foo-0.1.0.0

changed the description

Replying to [ticket:14775#comment:148781 phadej]:

TL;DR, I don't think this a valid issue. To fix, use up-to-data cabal-install.

@phadej, thank you for a very informative answer.

The oldest GHC version currently supported by Agda is 7.10.*. If I understand correctly, the proposed fixes require at least Cabal >= 1.24. Is there a fix which also work with the Cabal version (i.e. Cabal 1.22.*) shipped with GHC 7.10.3?

phadej, any update here?

As it was expected, I got the same issue with GHC 8.4.1. I'm waiting for a new release of cabal-install to see its behaviour on this situation.

Replying to [ticket:14775#comment:148861 asr]:

If I understand correctly, the proposed fixes require at least Cabal >= 1.24. Is there a fix which also work with the Cabal version (i.e. Cabal 1.22.*) shipped with GHC 7.10.3?

I realise that oldest versions of Cabal just ignore the custom setup stance, so please ignore my question.

closed

The issue in the OP was fixed in cabal-install upstream (tested in the 2.2 branch on this commit), so I'm closing it.

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedFixed

added Pnormal label