[commit: ghc] wip/T15696: Revert OK-for-spec change for the general app case (648dcd6)

[git at git.haskell.org]

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

On branch  : wip/T15696
Link       : http://ghc.haskell.org/trac/ghc/changeset/648dcd63164303e73feee05204ccb9cfed7aa658/ghc

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

commit 648dcd63164303e73feee05204ccb9cfed7aa658
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Wed Oct 17 10:16:37 2018 +0300

    Revert OK-for-spec change for the general app case


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

648dcd63164303e73feee05204ccb9cfed7aa658
 compiler/coreSyn/CoreUtils.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/coreSyn/CoreUtils.hs b/compiler/coreSyn/CoreUtils.hs
index ebdc31b..578c85e 100644
--- a/compiler/coreSyn/CoreUtils.hs
+++ b/compiler/coreSyn/CoreUtils.hs
@@ -1566,6 +1566,8 @@ app_ok primop_ok fun args
 
       _other -> isUnliftedType (idType fun)          -- c.f. the Var case of exprIsHNF
              || idArity fun > n_val_args             -- Partial apps
+             || (n_val_args == 0 &&
+                 isEvaldUnfolding (idUnfolding fun)) -- Let-bound values
              where
                n_val_args = valArgCount args
   where