Test Trac #7336

testsuite/tests/rename/should_compile/T7336.hs

+module T7336 ( U, T ) where
+
+data U = MkU deriving Show
+-- Want to report MkU as unused
+
+data T = MkT deriving Read
+-- But MkT is not unused; we might
+-- parse a string to generate it

testsuite/tests/rename/should_compile/T7336.stderr

+
+T7336.hs:3:10: Warning:
+    Defined but not used: data constructor `MkU'

testsuite/tests/rename/should_compile/all.T

@@ -201,3 +201,4 @@ test('dodgy',
      multimod_compile,
      ['dodgy', '-v0'])
 test('T7167', normal, compile, [''])
+test('T7336', normal, compile, ['-Wall'])