Build Log: base_quickcheck.v0.12.0

Can't find all required versions. Selected: ocaml-base-compiler.5.4.0 ocaml-config.3 ocaml-options-vanilla.1 ocaml&base_quickcheck ocaml-variants ocaml-base-compiler ocaml-base-compiler - base_quickcheck -> (problem) User requested = v0.12.0 No usable implementations: base_quickcheck.v0.17.1: Rejected by user-specified constraint base_quickcheck (= v0.12.0) base_quickcheck.v0.17.0: Rejected by user-specified constraint base_quickcheck (= v0.12.0) base_quickcheck.v0.16.0: Rejected by user-specified constraint base_quickcheck (= v0.12.0) base_quickcheck.v0.15.0: Rejected by user-specified constraint base_quickcheck (= v0.12.0) base_quickcheck.v0.14.1: Rejected by user-specified constraint base_quickcheck (= v0.12.0) ... - ocaml -> ocaml.5.2.1 User requested = 5.2.1 - ocaml-compiler -> (problem) ocaml-base-compiler 5.4.0 requires = 5.4.0 Rejected candidates: ocaml-compiler.5.5: Incompatible with restriction: = 5.4.0 ocaml-compiler.5.4.0: Requires ocaml = 5.4.0 ocaml-compiler.5.4.0~rc1: Incompatible with restriction: = 5.4.0 ocaml-compiler.5.4.0~beta2: Incompatible with restriction: = 5.4.0 ocaml-compiler.5.4.0~beta1: Incompatible with restriction: = 5.4.0 ... - ocaml-variants -> (problem) Rejected candidates: ocaml-variants.5.5.0+trunk: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler ocaml-variants.5.4.1+trunk: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler ocaml-variants.5.4.0+options: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler ocaml-variants.5.4.0~rc1+options: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler ocaml-variants.5.4.0~beta2+options: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler ...