1 files changed, 30 insertions, 0 deletions
diff --git a/testsuite/tests/codeGen/should_compile/cg004.hs b/testsuite/tests/codeGen/should_compile/cg004.hs
new file mode 100644
index 0000000000..fb8e3cc413
--- /dev/null
+++ b/testsuite/tests/codeGen/should_compile/cg004.hs
@@ -0,0 +1,30 @@
+module ShouldCompile where
+
+-- 		Killed GHC 6.0 in isCrossDllArg
+--
+-- ghc-6.0: panic! (the `impossible' happened, GHC version 6.0):
+--	coreSyn/CoreUtils.lhs:1188: Non-exhaustive patterns in function isCrossDllArg
+--
+-- The reason was that newST had the form
+--   newST = \ @ v -> GHC.Base.:
+--			@ (Environment.Scope v)
+--			(case $fScopeOpersScope @ v
+--			 of tpl_B1 { Environment.:DScopeOpers tpl_B2 tpl_B3 ->
+--			 tpl_B2
+--			 })
+--			(GHC.Base.[] @ (Environment.Scope v))
+
+class ScopeOpers s where
+      emptyScope :: s 
+      op :: s -> s
+
+data Scope v = NewScope 
+
+instance ScopeOpers (Scope v) where
+      emptyScope = error "emptyScope"
+      op = error "op"
+
+newtype SymbolTable v = SymbolTable [Scope v]
+
+newST :: SymbolTable v
+newST = SymbolTable [emptyScope]