Unable to parse integer-gmp's Cabal file
integer-gmp version 188.8.131.52 has this line in its Cabal file:
build-depends: ghc-prim ^>= 0.5.1.0
That uses the new caret constraint syntax. That syntax was introduced by Cabal 2 a few months ago in July/August. Attempting to build integer-gmp with a slightly older version of Cabal, like 184.108.40.206, or with the latest released version of Stack (1.5.1) fails with this error:
Unable to parse cabal file for integer-gmp-220.127.116.11: NoParse "build-depends" 58
This was reported on Stack's issue tracker and on Reddit:
I was not able to find an issue tracker for integer-gmp. Someone suggested that I open an issue here instead.
I can see how this isn't a bug per se because integer-gmp's Cabal file specifies
cabal-version: 2.0. Nevertheless, it's frustrating that a core library is using a bleeding edge feature for basically no reason. It would be nice if integer-gmp used the more typical
cabal-version: >= 1.10 and specified its dependency as
build-depends: ghc-prim >= 0.5.1 && <0.6, without the caret operator.