I'll note that package regex-base-0.93.2 requires mtl-2.1.2 is indeed in my system global database, and it seems like new-build is treating it as sticky. Since the mtl it was built against is too old, it can't solve this problem.
@ezyang can you check if this is still true in the nix-local-build branch with the solver patches that are in there now (vs 1.24 that doesn't have those patches yet).
Here's what I get:
I'll note that
package regex-base-0.93.2 requires mtl-2.1.2
is indeed in my system global database, and it seems likenew-build
is treating it as sticky. Since the mtl it was built against is too old, it can't solve this problem.