libstdc++ 4.4 uses __is_signed as an identifier, while Clang treats it
as a keyword for the __is_signed type trait. Cope with this conflict
via some hackish recovery: if we see a declaration of the form

 static const bool __is_signed

then we stop treating __is_signed as a keyword and instead treat it as
an identifier. It's ugly, but it's better than making the __is_signed
type trait conditional on some language flag. Fixes PR9804.

llvm-svn: 130399
diff --git a/clang/test/SemaCXX/libstdcxx_is_pod_hack.cpp b/clang/test/SemaCXX/libstdcxx_is_pod_hack.cpp
index 2e92032..3cc476d 100644
--- a/clang/test/SemaCXX/libstdcxx_is_pod_hack.cpp
+++ b/clang/test/SemaCXX/libstdcxx_is_pod_hack.cpp
@@ -11,3 +11,12 @@
 };
 
 __is_pod<int> ipi;
+
+// Another, similar egregious hack for __is_signed, which is a type
+// trait in Embarcadero's compiler but is used as an identifier in
+// libstdc++.
+struct test_is_signed {
+  static const bool __is_signed = true;
+};
+
+bool check_signed = test_is_signed::__is_signed;