Test Trac #2714

testsuite/tests/ghc-regress/typecheck/should_fail/T2714.hs

+{-# LANGUAGE ScopedTypeVariables #-}
+
+-- Trac #2714
+
+module T2714 where
+
+f :: ((a -> b) -> b) -> (forall c. c -> a)
+f = fmap 

testsuite/tests/ghc-regress/typecheck/should_fail/T2714.stderr

+
+T2714.hs:8:4:
+    Couldn't match expected type `a' against inferred type `f b'
+      `a' is a rigid type variable bound by
+          the type signature for `f' at T2714.hs:7:7
+    In the expression: fmap
+    In the definition of `f': f = fmap
+
+T2714.hs:8:4:
+    Couldn't match expected type `c'
+           against inferred type `f (f b -> b)'
+      `c' is a rigid type variable bound by
+          the polymorphic type `forall c. c -> a' at T2714.hs:8:4
+    In the expression: fmap
+    In the definition of `f': f = fmap

testsuite/tests/ghc-regress/typecheck/should_fail/all.T

@@ -199,3 +199,4 @@ test('T2307', normal, compile_fail, [''])
 test('T2414', normal, compile_fail, [''])
 test('T2538', normal, compile_fail, [''])
 test('T2688', normal, compile_fail, [''])
+test('T2714', normal, compile_fail, [''])