Handle redeclarations found by ADL deterministically and reasonably.

This solution relies on an O(n) scan of redeclarations, which means it might
scale poorly in crazy cases with tons of redeclarations brought in by a ton
of distinct associated namespaces.  I believe that avoiding this
is not worth the common-case cost.

llvm-svn: 94530

1 files changed, 18 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/using-decl-1.cpp b/clang/test/SemaCXX/using-decl-1.cpp
index eb41e6630fe..30c4cfd997a 100644
--- a/clang/test/SemaCXX/using-decl-1.cpp
+++ b/clang/test/SemaCXX/using-decl-1.cpp
@@ -77,3 +77,21 @@ namespace test0 {
     foo(*p); // expected-error {{no matching function for call to 'foo'}}
   }
 }
+
+// Redeclarations!
+namespace test1 {
+  namespace ns0 { struct Foo {}; }
+  namespace A { void foo(ns0::Foo *p, int y, int z); }
+  namespace ns2 { using A::foo; }
+  namespace ns1 { struct Bar : ns0::Foo {}; }
+  namespace A { void foo(ns0::Foo *p, int y, int z = 0); } // expected-note {{candidate}}
+  namespace ns1 { using A::foo; }
+  namespace ns2 { struct Baz : ns1::Bar {}; }
+  namespace A { void foo(ns0::Foo *p, int y = 0, int z); }
+
+  void test(ns2::Baz *p) {
+    foo(p, 0, 0); // okay!
+    foo(p, 0); // should be fine!
+    foo(p); // expected-error {{no matching function}}
+  }
+}