Right now the plugin creates coercions for its rewrites. But any constraints that justify the rewrite are not mentioned by the coercion. If c enables a rewrite from A to B, we just create a coercion from A to B that doesn't mention c. But it should mention c, and that's the goal of this issue.
Right now the plugin creates coercions for its rewrites. But any constraints that justify the rewrite are not mentioned by the coercion. If
cenables a rewrite fromAtoB, we just create a coercion fromAtoBthat doesn't mentionc. But it should mentionc, and that's the goal of this issue.The comments on https://gitlab.haskell.org/ghc/ghc/issues/15248 sound like it might be harder than I was anticipating.