Add in Incoherent Instances test for Safe Haskell.

3 files changed, 20 insertions, 0 deletions

diff --git a/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.hs b/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.hs
new file mode 100644
index 0000000000..04591b5f77
--- /dev/null
+++ b/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.hs
@@ -0,0 +1,10 @@
+{-# OPTIONS_GHC -fwarn-unsafe -Werror #-}
+{-# LANGUAGE FlexibleInstances #-}
+module UnsafeInfered15 where
+
+class C a where
+  f :: a -> String
+
+instance {-# INCOHERENT #-} C a where
+  f _ = "a"
+
diff --git a/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.stderr b/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.stderr
new file mode 100644
index 0000000000..415e9a1f37
--- /dev/null
+++ b/testsuite/tests/safeHaskell/safeInfered/UnsafeInfered17.stderr
@@ -0,0 +1,9 @@
+
+UnsafeInfered17.hs:1:16: Warning:
+    ‘UnsafeInfered15’ has been inferred as unsafe!
+    Reason:
+        UnsafeInfered17.hs:8:29:
+            [incoherent] overlap mode isn't allowed in Safe Haskell
+
+<no location info>: 
+Failing due to -Werror.
diff --git a/testsuite/tests/safeHaskell/safeInfered/all.T b/testsuite/tests/safeHaskell/safeInfered/all.T
index a9600fa1c2..4fc9fcecb8 100644
--- a/testsuite/tests/safeHaskell/safeInfered/all.T
+++ b/testsuite/tests/safeHaskell/safeInfered/all.T
@@ -64,6 +64,7 @@ test('UnsafeInfered13', normal, compile_fail, [''])
 test('UnsafeInfered14', normal, compile_fail, [''])
 test('UnsafeInfered15', normal, compile_fail, [''])
 test('UnsafeInfered16', normal, compile_fail, [''])
+test('UnsafeInfered17', normal, compile_fail, [''])
 
 # Mixed tests
 test('Mixed01', normal, compile_fail, [''])