The build is unreachable.

Build log

> /tmp/stackage-build2456$ stack unpack dlist-0.8.0.5@sha256:173bc132a63f29660de117eca5ee22bf3205675c7d5dd1f3e3779621d70c6d1a
Unpacked dlist-0.8.0.5 to /tmp/stackage-build2456/dlist-0.8.0.5/
> /tmp/stackage-build2456/dlist-0.8.0.5$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
[1 of 1] Compiling Main             ( Setup.hs, Setup.o )
Linking Setup ...
> /tmp/stackage-build2456/dlist-0.8.0.5$ ./Setup configure --package-db=clear --package-db=global --package-db=/home/circleci/project/builds/nightly/pkgdb --libdir=/home/circleci/project/builds/nightly/lib --bindir=/home/circleci/project/builds/nightly/bin --datadir=/home/circleci/project/builds/nightly/share --libexecdir=/home/circleci/project/builds/nightly/libexec --sysconfdir=/home/circleci/project/builds/nightly/etc --docdir=/home/circleci/project/builds/nightly/doc/dlist-0.8.0.5 --htmldir=/home/circleci/project/builds/nightly/doc/dlist-0.8.0.5 --haddockdir=/home/circleci/project/builds/nightly/doc/dlist-0.8.0.5
Configuring dlist-0.8.0.5...
> /tmp/stackage-build2456/dlist-0.8.0.5$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2456/dlist-0.8.0.5$ ./Setup build
Preprocessing library for dlist-0.8.0.5..
Building library for dlist-0.8.0.5..
[1 of 1] Compiling Data.DList       ( Data/DList.hs, dist/build/Data/DList.o )
> /tmp/stackage-build2456/dlist-0.8.0.5$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2456/dlist-0.8.0.5$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181117/dlist-0.8.0.5-FMMQwM1hD2kK7b7715Z2vG
> /tmp/stackage-build2456/dlist-0.8.0.5$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2456/dlist-0.8.0.5$ ./Setup register
Registering library for dlist-0.8.0.5..