Lazy patterns can't be unboxed (Trac 845)

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

@@ -143,3 +143,4 @@ test('tcfail155', normal, compile_fail, [''])
 test('tcfail156', normal, compile_fail, [''])
 test('tcfail157', normal, compile_fail, [''])
 test('tcfail158', normal, compile_fail, [''])
+test('tcfail159', normal, compile_fail, [''])

testsuite/tests/ghc-regress/typecheck/should_fail/tcfail159.hs

+{-# OPTIONS -fglasgow-exts #-}
+
+module ShouldFail where
+
+h :: Int -> (# Int, Int #)
+h x = (# x,x #)
+
+foo x = case h x of 
+	  ~(# p, q #) -> p

testsuite/tests/ghc-regress/typecheck/should_fail/tcfail159.stderr

+
+tcfail159.hs:9:3:
+    Couldn't match kind `(#)' against `*'
+    When matching the kinds of `(# Int, Int #) :: (#)' and `bx :: *'
+      Expected type: bx
+      Inferred type: (# Int, Int #)
+    In the pattern: ~(# p, q #)