The build is unreachable.

Build log

> /tmp/stackage-build2451$ stack unpack fingertree-0.1.4.1@sha256:165408a651107150cf99da8f16d9ae98274f82349395a0e3f91a5d1eef82e079
Unpacked fingertree-0.1.4.1 to /tmp/stackage-build2451/fingertree-0.1.4.1/
> /tmp/stackage-build2451/fingertree-0.1.4.1$ 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-build2451/fingertree-0.1.4.1$ ./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/fingertree-0.1.4.1 --htmldir=/home/circleci/project/builds/nightly/doc/fingertree-0.1.4.1 --haddockdir=/home/circleci/project/builds/nightly/doc/fingertree-0.1.4.1
Configuring fingertree-0.1.4.1...
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ./Setup build
Preprocessing library for fingertree-0.1.4.1..
Building library for fingertree-0.1.4.1..

Data/FingerTree.hs:13:14: warning:
    -XAutoDeriveTypeable is deprecated: Typeable instances are created automatically for all types since GHC 8.2.
   |
13 | {-# LANGUAGE AutoDeriveTypeable #-}
   |              ^^^^^^^^^^^^^^^^^^

Data/IntervalMap/FingerTree.hs:10:14: warning:
    -XAutoDeriveTypeable is deprecated: Typeable instances are created automatically for all types since GHC 8.2.
   |
10 | {-# LANGUAGE AutoDeriveTypeable #-}
   |              ^^^^^^^^^^^^^^^^^^

Data/PriorityQueue/FingerTree.hs:10:14: warning:
    -XAutoDeriveTypeable is deprecated: Typeable instances are created automatically for all types since GHC 8.2.
   |
10 | {-# LANGUAGE AutoDeriveTypeable #-}
   |              ^^^^^^^^^^^^^^^^^^
[1 of 3] Compiling Data.FingerTree  ( Data/FingerTree.hs, dist/build/Data/FingerTree.o )
[2 of 3] Compiling Data.IntervalMap.FingerTree ( Data/IntervalMap/FingerTree.hs, dist/build/Data/IntervalMap/FingerTree.o )
[3 of 3] Compiling Data.PriorityQueue.FingerTree ( Data/PriorityQueue/FingerTree.hs, dist/build/Data/PriorityQueue/FingerTree.o )
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181121/fingertree-0.1.4.1-5BU0avpu56MPok7EV1nGy
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/fingertree-0.1.4.1$ ./Setup register
Registering library for fingertree-0.1.4.1..