The build is unreachable.

Build log

> /tmp/stackage-build2454$ stack unpack safe-0.3.17@sha256:a522024ec60a9bef6ad1df2117023785b0f97ed732d9af9908cd1d09530e977f
Unpacked safe-0.3.17 to /tmp/stackage-build2454/safe-0.3.17/
> /tmp/stackage-build2454/safe-0.3.17$ 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-build2454/safe-0.3.17$ ./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/safe-0.3.17 --htmldir=/home/circleci/project/builds/nightly/doc/safe-0.3.17 --haddockdir=/home/circleci/project/builds/nightly/doc/safe-0.3.17
Configuring safe-0.3.17...
> /tmp/stackage-build2454/safe-0.3.17$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2454/safe-0.3.17$ ./Setup build
Preprocessing library for safe-0.3.17..
Building library for safe-0.3.17..
[1 of 5] Compiling Safe.Partial     ( Safe/Partial.hs, dist/build/Safe/Partial.o )
[2 of 5] Compiling Safe.Util        ( Safe/Util.hs, dist/build/Safe/Util.o )
[3 of 5] Compiling Safe.Foldable    ( Safe/Foldable.hs, dist/build/Safe/Foldable.o )
[4 of 5] Compiling Safe.Exact       ( Safe/Exact.hs, dist/build/Safe/Exact.o )
[5 of 5] Compiling Safe             ( Safe.hs, dist/build/Safe.o )
> /tmp/stackage-build2454/safe-0.3.17$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2454/safe-0.3.17$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181122/safe-0.3.17-43oyx4B630gDZMbTh3Ttji
> /tmp/stackage-build2454/safe-0.3.17$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2454/safe-0.3.17$ ./Setup register
Registering library for safe-0.3.17..