Kill off redundant SigTv check in occurCheckExpand
authorSimon Peyton Jones <simonpj@microsoft.com>
Mon, 16 May 2016 21:08:08 +0000 (22:08 +0100)
committerSimon Peyton Jones <simonpj@microsoft.com>
Mon, 13 Jun 2016 09:50:19 +0000 (10:50 +0100)
commitd25cb61a1c2a135a2564143a332f8b2962f134bc
treea5b6f3f9ff310b1d172d975ab4ac3dd549867489
parent2bb6ba62b8d0e9c79b59e39e225758cf999eff83
Kill off redundant SigTv check in occurCheckExpand

This patch simply deletes code, the SigTv check in
occurCheckExpand.  As the new comment says

In the past we also rejected a SigTv matched with a non-tyvar
But it is wrong to reject that for Givens;
and SigTv is in any case handled separately by
   - TcUnify.checkTauTvUpdate (on-the-fly unifier)
   - TcInteract.canSolveByUnification (main constraint solver)
compiler/typecheck/TcType.hs