Commit a3cc9a29 authored by Committed by Marge Bot
Fix #19649 by using filterInScopeM in rnFamEqn
Previously, associated type family instances would incorrectly claim to implicitly quantify over type variables bound by the instance head in the `HsOuterImplicit`s that `rnFamEqn` returned. This is fixed by using `filterInScopeM` to filter out any type variables that the instance head binds. Fixes #19649.