The build is unreachable.

Build log

> /tmp/stackage-build2451$ stack unpack siphash-1.0.3@sha256:d629325f124617deeb6f1b172c8cbb30556090b32f3533cf8ea93ecb3df04de0
Unpacked siphash-1.0.3 to /tmp/stackage-build2451/siphash-1.0.3/
> /tmp/stackage-build2451/siphash-1.0.3$ 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/siphash-1.0.3$ ./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/siphash-1.0.3 --htmldir=/home/circleci/project/builds/nightly/doc/siphash-1.0.3 --haddockdir=/home/circleci/project/builds/nightly/doc/siphash-1.0.3
Configuring siphash-1.0.3...
> /tmp/stackage-build2451/siphash-1.0.3$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/siphash-1.0.3$ ./Setup build
Preprocessing library for siphash-1.0.3..
Building library for siphash-1.0.3..
[1 of 1] Compiling Crypto.MAC.SipHash ( Crypto/MAC/SipHash.hs, dist/build/Crypto/MAC/SipHash.o )

Crypto/MAC/SipHash.hs:46:33: warning: [-Wdeprecations]
    In the use of ‘inlinePerformIO’
    (imported from Data.ByteString.Internal):
    Deprecated: "If you think you know what you are doing, use 'unsafePerformIO'. If you are sure you know what you are doing, use 'unsafeDupablePerformIO'. If you enjoy sharing an address space with a malevolent agent of chaos, try 'accursedUnutterablePerformIO'."
   |
46 | hashWith c d key (PS ps s fl) = inlinePerformIO $ withForeignPtr ps (\ptr -> runHash (initSip key) (ptr `plusPtr` s) fl)
   |                                 ^^^^^^^^^^^^^^^
> /tmp/stackage-build2451/siphash-1.0.3$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/siphash-1.0.3$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181119/siphash-1.0.3-BVEok4bLpPb1uE8wxmsIZC
> /tmp/stackage-build2451/siphash-1.0.3$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/siphash-1.0.3$ ./Setup register
Registering library for siphash-1.0.3..