Test for Trac #1680

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

@@ -8,3 +8,4 @@ setTestOpts(f)
 
 test('cc005', only_compiler_types(['ghc']), compile_fail, [''])
 test('ccfail001', only_compiler_types(['ghc']), compile_fail, [''])
+test('ccfail002', only_compiler_types(['ghc']), compile_fail, [''])

testsuite/tests/ghc-regress/ccall/should_fail/ccfail002.hs

+{-# OPTIONS -fglasgow-exts -fffi #-}
+
+-- Test for Trac #1680
+
+module ShouldFail where
+
+import GHC.Exts
+
+foreign import ccall unsafe "foo" 
+	foo :: Int# -> Int# -> Int# -> (# Int# , Int#, Int# #)

testsuite/tests/ghc-regress/ccall/should_fail/ccfail002.stderr

+
+ccfail002.hs:6:0:
+    Unacceptable result type in foreign declaration:
+	(# Int#, Int#, Int# #)
+    When checking declaration:
+	foreign import ccall unsafe "static  &foo" foo
+	  :: Int# -> Int# -> Int# -> (# Int#, Int#, Int# #)