[commit: ghc] wip/T13861: WIP: add another test [ci skip] (c2c396c)

[git at git.haskell.org]

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

On branch  : wip/T13861
Link       : http://ghc.haskell.org/trac/ghc/changeset/c2c396c36a5b6332efb67f7621fa0cb53974e0c9/ghc

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

commit c2c396c36a5b6332efb67f7621fa0cb53974e0c9
Author: Gabor Greif <ggreif at gmail.com>
Date:   Wed Dec 27 21:15:17 2017 +0100

    WIP: add another test [ci skip]


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

c2c396c36a5b6332efb67f7621fa0cb53974e0c9
 testsuite/tests/simplStg/should_run/T13861.hs     | 9 +++++++--
 testsuite/tests/simplStg/should_run/T13861.stdout | 1 +
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/testsuite/tests/simplStg/should_run/T13861.hs b/testsuite/tests/simplStg/should_run/T13861.hs
index 4130a51..fed0e7a 100644
--- a/testsuite/tests/simplStg/should_run/T13861.hs
+++ b/testsuite/tests/simplStg/should_run/T13861.hs
@@ -56,6 +56,9 @@ eq1 :: a :~: b -> [a]
 eq1 Refl = []
 {-# NOINLINE eq1 #-}
 
+eq2 :: a :~: b -> b :~: a
+eq2 Refl = Refl
+{-# NOINLINE eq2 #-}
 
 
 test x = do
@@ -69,11 +72,13 @@ test x = do
     let (r40, r41) = (['l'], baz r40)
     (same $! r40) $! r41                -- no, arity mismatch
     let (r42, r43) = ([], baz r42)
-    (same $! r42) $! r43                -- no, WHY?
+    (same $! r42) $! r43                -- yes
     let (r44, r45) = ("ab", baz r44)
     (same $! r44) $! r45                -- no, arity mismatch
     let (r46, r47) = (Refl, eq1 r46)
-    (same $! r46) $! r47                -- no, WHY?
+    (same $! r46) $! r47                -- no, GADT
+    let (r48, r49) = (Refl, eq2 r48)
+    (same $! r48) $! r49                -- no, GADT
 
     let (r4,_) = bar r1
     let r5 = nested r4
diff --git a/testsuite/tests/simplStg/should_run/T13861.stdout b/testsuite/tests/simplStg/should_run/T13861.stdout
index 40aa293..d1124c6 100644
--- a/testsuite/tests/simplStg/should_run/T13861.stdout
+++ b/testsuite/tests/simplStg/should_run/T13861.stdout
@@ -5,6 +5,7 @@ no
 yes
 no
 no
+no
 yes
 yes
 no