Incorrect constraint warnings from ghc 9.2.4
With the constraint, I get a redundant constraint warning and without it, i get a missing constraint warning.
Steps to reproduce
Minimal reproduction case redundant-constraint.tgz
WIth the code in the tarball I get:
• Redundant constraints: (Applicative m, Monad m) • In the instance declaration for ‘ReportSchemaErrors m’
If I remove those constraints I get:
• Could not deduce (Applicative m) • Could not deduce (Monad m)
The constraint cannot be both redundant and required.
class declaration is in the same file as the instance decalration its fine.
After removing the redundant constraints, there should be no warning.
- GHC version used: 9.2.4
- Operating System: Linux
- System Architecture: x86_64