Report errors on duplicate export.

tests/language/language.status

Index: tests/language/language.status
diff --git a/tests/language/language.status b/tests/language/language.status
index 3c1ccfeb5ce017ee6e5b36b08c162f9caa53245a..357b3c4edcb9d917e7c107b7f92a53880059c5e0 100644
--- a/tests/language/language.status
+++ b/tests/language/language.status
@@ -54,6 +54,7 @@ invocation_mirror_test: Fail # issue 3326, 3622.
 no_such_method_test: Fail # issue 3326, 3622.
 
 export_cyclic_test: Fail, Crash # issue 6060
+duplicate_export_negative_test: Fail # issue 6134
 invocation_mirror_indirect_test: Fail # Issue 3326
 
 [ $compiler == none && ($system == macos || $system == linux) && $arch == ia32 && $checked ]
@@ -147,6 +148,7 @@ first_class_types_literals_test: Fail # issue 6283
 getter_no_setter_test/01: Fail # Fails to detect compile-time error.
 getter_no_setter2_test/01: Fail # Fails to detect compile-time error.
 instance_call_wrong_argument_count_negative_test: Fail # Runtime only test, rewrite as multitest
+duplicate_export_negative_test: Fail # Duplicate export not reported.
 # Test expects signature of noSuchMethod to be correct according
 # to specification. Should start working when the library signature
 # changes.