[commit: ghc] master: TcUnify: Assert precondition of matchExpectedTyConApp (6626242)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/6626242ba334d81ecf5fe6dd4ef964f74656e541/ghc

>---------------------------------------------------------------

commit 6626242ba334d81ecf5fe6dd4ef964f74656e541
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Tue Feb 14 09:31:08 2017 -0500

    TcUnify: Assert precondition of matchExpectedTyConApp
    
    Test Plan: Validate
    
    Reviewers: simonpj, austin
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D3128


>---------------------------------------------------------------

6626242ba334d81ecf5fe6dd4ef964f74656e541
 compiler/typecheck/TcUnify.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/typecheck/TcUnify.hs b/compiler/typecheck/TcUnify.hs
index b7c4aee..db3233e 100644
--- a/compiler/typecheck/TcUnify.hs
+++ b/compiler/typecheck/TcUnify.hs
@@ -367,7 +367,7 @@ matchExpectedTyConApp :: TyCon                -- T :: forall kv1 ... kvm. k1 ->
 -- Postcondition: (T k1 k2 k3 a b c) is well-kinded
 
 matchExpectedTyConApp tc orig_ty
-  = go orig_ty
+  = ASSERT(tc /= funTyCon) go orig_ty
   where
     go ty
        | Just ty' <- coreView ty