When trying to emerge dev-haskell/cabal-220.127.116.11-r1, the ebuild fails with the following message:
* Messages for package dev-haskell/cabal-18.104.22.168-r1:
* Cabal package 'Cabal-22.214.171.124' is shipped with 'PM:8.10.4-r1' ('8.10.4').
* Ebuild author forgot an entry in CABAL_CORE_LIB_GHC_PV='PM:8.10.3 PM:8.10.4 PM:8.10.5 PM:8.10.5-r1 PM:8.10.6 PM:8.10.7 PM:9999'.
* Found in /usr/lib64/ghc-8.10.4/package.conf.d.initial.
* ERROR: dev-haskell/cabal-126.96.36.199-r1::haskell failed (install phase):
* (no error message)
* Call stack:
* ebuild.sh, line 127: Called src_install
* environment, line 1769: Called haskell-cabal_src_install
* environment, line 1455: Called cabal_src_install
* environment, line 673: Called cabal-pkg
* environment, line 555: Called ghc-install-pkg '/var/tmp/portage/dev-haskell/cabal-188.8.131.52-r1/temp/cabal-184.108.40.206.conf'
* environment, line 1291: Called check-for-collisions '/var/tmp/portage/dev-haskell/cabal-220.127.116.11-r1/temp/cabal-18.104.22.168-r1.conf.d'
* environment, line 694: Called die
* The specific snippet of code:
* If you need support, post the output of `emerge --info '=dev-haskell/cabal-22.214.171.124-r1::haskell'`,
* the complete build log and the output of `emerge -pqv '=dev-haskell/cabal-126.96.36.199-r1::haskell'`.
* The complete build log is located at '/var/tmp/portage/dev-haskell/cabal-188.8.131.52-r1/temp/build.log'.
* The ebuild environment file is located at '/var/tmp/portage/dev-haskell/cabal-184.108.40.206-r1/temp/environment'.
* Working directory: '/var/tmp/portage/dev-haskell/cabal-220.127.116.11-r1/work/Cabal-18.104.22.168'
* S: '/var/tmp/portage/dev-haskell/cabal-22.214.171.124-r1/work/Cabal-126.96.36.199'
output of emerge -pqv '=dev-haskell/cabal-188.8.131.52-r1::haskell' :
[ebuild R ] dev-haskell/cabal-184.108.40.206-r1 [220.127.116.11-r1] USE="-doc -hoogle% -hscolour -profile"
I can provide additional information if needed. Especially, I cannot post the output of emerge --info yet because it contains urls and I just created my bugzilla account today, but I definitely can add this later if it is helpful.
Note: it looks similar to #833848 but with version 18.104.22.168-r1 this time.