Resolving dependencies...
Starting     ghc-datasize-0.2.5
Building     ghc-datasize-0.2.5
Failed to install ghc-datasize-0.2.5
Build log ( /home/builder/.cabal/logs/ghc-8.10.2/ghc-datasize-0.2.5-AyLNffndk1R2tUvuO1BQ4J.log ):
cabal: Entering directory '/tmp/cabal-tmp-16611/ghc-datasize-0.2.5'
Configuring ghc-datasize-0.2.5...
Preprocessing library for ghc-datasize-0.2.5..
Building library for ghc-datasize-0.2.5..
[1 of 1] Compiling GHC.DataSize     ( src/GHC/DataSize.hs, dist/build/GHC/DataSize.o, dist/build/GHC/DataSize.dyn_o )

src/GHC/DataSize.hs:23:1: error:
    Could not load module GHC.Exts.Heap
    It is a member of the hidden package ghc-heap-8.10.2.
    Perhaps you need to add ghc-heap to the build-depends in your .cabal file.
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
   |
23 | import GHC.Exts.Heap hiding (size)
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

src/GHC/DataSize.hs:24:1: error:
    Could not load module GHC.Exts.Heap.Constants
    It is a member of the hidden package ghc-heap-8.10.2.
    Perhaps you need to add ghc-heap to the build-depends in your .cabal file.
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
   |
24 | import GHC.Exts.Heap.Constants (wORD_SIZE)
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-16611/ghc-datasize-0.2.5'
cabal: Error: some packages failed to install:
ghc-datasize-0.2.5-AyLNffndk1R2tUvuO1BQ4J failed during the building phase.
The exception was:
ExitFailure 1