Improve error messages for recursive superclasses
authorSimon Peyton Jones <simonpj@microsoft.com>
Mon, 8 Feb 2016 13:31:11 +0000 (13:31 +0000)
committerSimon Peyton Jones <simonpj@microsoft.com>
Mon, 8 Feb 2016 15:08:48 +0000 (15:08 +0000)
commitd6b68be1100203aa13755457f89ee4bbb0297473
tree13e167ce08c938233f5a0cea229cb1d20e5da2e5
parent72129686a319406e0c317619d1ba521a7f5b25f3
Improve error messages for recursive superclasses

If we fail to typecheck by blowing the constraint simplifier
iteration limit, we want to see the limit-blowing meessage.
Previously it was being suppressed by the type /error/, which
suppress the iteration-limit /warning/.  Solution: make the
iteration-limit message into an error.
compiler/typecheck/TcSMonad.hs
compiler/typecheck/TcSimplify.hs