build failure with ghc 8.6.3

  /tmp/stack19773/postgresql-query-3.5.0/src/Database/PostgreSQL/Query/Entity/Functions.hs:279:5: error:
        • Could not deduce (Control.Monad.Fail.MonadFail m)
            arising from a do statement
            with the failable pattern ‘[[c]]’
          from the context: (Entity a, MonadPostgres m, ToSqlBuilder q)
            bound by the type signature for:
                       pgSelectCount :: forall (m :: * -> *) a q.
                                        (Entity a, MonadPostgres m, MonadLogger m, ToSqlBuilder q) =>
                                        Proxy a -> q -> m Integer
            at src/Database/PostgreSQL/Query/Entity/Functions.hs:(272,1)-(277,14)
          Possible fix:
            add (Control.Monad.Fail.MonadFail m) to the context of
              the type signature for:
                pgSelectCount :: forall (m :: * -> *) a q.
                                 (Entity a, MonadPostgres m, MonadLogger m, ToSqlBuilder q) =>
                                 Proxy a -> q -> m Integer
        • In a stmt of a 'do' block:
            [[c]] <- pgQuery
                       (mconcat
                          [sqlBuilderFromByteString
                             (GHC.IO.Unsafe.unsafePerformIO
                                ((Data.ByteString.Unsafe.unsafePackAddressLen 22)
                                   "SELECT count(id) FROM "#)),
                           toSqlBuilder (tableName p),
                           sqlBuilderFromByteString
                             (GHC.IO.Unsafe.unsafePerformIO
                                ((Data.ByteString.Unsafe.unsafePackAddressLen 1) " "#)),
                           toSqlBuilder q])
          In the expression:
            do [[c]] <- pgQuery
                          (mconcat
                             [sqlBuilderFromByteString
                                (GHC.IO.Unsafe.unsafePerformIO
                                   ((Data.ByteString.Unsafe.unsafePackAddressLen 22)
                                      "SELECT count(id) FROM "#)),
                              toSqlBuilder (tableName p), ....])
               return c
          In an equation for ‘pgSelectCount’:
              pgSelectCount p q
                = do [[c]] <- pgQuery
                                (mconcat
                                   [sqlBuilderFromByteString
                                      (GHC.IO.Unsafe.unsafePerformIO
                                         ((Data.ByteString.Unsafe.unsafePackAddressLen 22)
                                            "SELECT count(id) FROM "#)),
                                    ....])
                     return c
        |
    279 |     [[c]] <- pgQuery [sqlExp|SELECT count(id) FROM ^{tableName p} ^{q}|]
        |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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