Push alias-declarations and alias-template declarations into scope even if

they're redeclarations. This is necessary in order for name lookup to correctly
find the most recent declaration of the name (which affects default template
argument lookup and cross-module merging, among other things).

llvm-svn: 275612

7 files changed, 21 insertions, 10 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 22334ab253c..e161c87f173 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -8885,9 +8885,7 @@ Decl *Sema::ActOnAliasDeclaration(Scope *S,
     NewND = NewTD;
   }
 
-  if (!Redeclaration)
-    PushOnScopeChains(NewND, S);
-
+  PushOnScopeChains(NewND, S);
   ActOnDocumentableDecl(NewND);
   return NewND;
 }
diff --git a/clang/test/CXX/dcl.dcl/dcl.spec/dcl.typedef/p2-0x.cpp b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.typedef/p2-0x.cpp
index 20b5104f83b..8c6f6e5ddc7 100644
--- a/clang/test/CXX/dcl.dcl/dcl.spec/dcl.typedef/p2-0x.cpp
+++ b/clang/test/CXX/dcl.dcl/dcl.spec/dcl.typedef/p2-0x.cpp
@@ -38,8 +38,8 @@ namespace VariableLengthArrays {
   using T = int[n]; // expected-error {{variable length array declaration not allowed at file scope}}
 
   const int m = 42;
-  using U = int[m]; // expected-note {{previous definition}}
-  using U = int[42]; // ok
+  using U = int[m];
+  using U = int[42]; // expected-note {{previous definition}}
   using U = int; // expected-error {{type alias redefinition with different types ('int' vs 'int [42]')}}
 
   void f() {
diff --git a/clang/test/CXX/drs/dr6xx.cpp b/clang/test/CXX/drs/dr6xx.cpp
index 988c8f43011..1d37a6d3e80 100644
--- a/clang/test/CXX/drs/dr6xx.cpp
+++ b/clang/test/CXX/drs/dr6xx.cpp
@@ -146,9 +146,9 @@ namespace dr616 { // dr616: no
 #if __cplusplus >= 201103L
   struct S { int n; } s;
   // FIXME: These should all be 'int &&'
-  using T = decltype(S().n); // expected-note 2{{previous}}
+  using T = decltype(S().n);
   using T = decltype(static_cast<S&&>(s).n);
-  using T = decltype(S().*&S::n);
+  using T = decltype(S().*&S::n); // expected-note 2{{previous}}
   using T = decltype(static_cast<S&&>(s).*&S::n); // expected-error {{different type}}
   using T = int&&; // expected-error {{different type}}
 #endif
diff --git a/clang/test/CXX/temp/temp.param/p15-cxx0x.cpp b/clang/test/CXX/temp/temp.param/p15-cxx0x.cpp
index ade192b3efa..667152da1cb 100644
--- a/clang/test/CXX/temp/temp.param/p15-cxx0x.cpp
+++ b/clang/test/CXX/temp/temp.param/p15-cxx0x.cpp
@@ -102,10 +102,10 @@ using D1 = drop<3, int, char, double, long>::type;
 using D1 = types<long>;
 
 using T2 = take<4, int, char, double, long>::type; // expected-note {{previous}}
-using T2 = types<int, char, double, long>;
 // FIXME: Desguar the types on the RHS in this diagnostic.
 // desired-error {{'types<void, void, void, void>' vs 'types<int, char, double, long>'}}
 using T2 = types<void, void, void, void>; // expected-error {{'types<void, void, void, void>' vs 'types<typename inner<_>::type, typename inner<_>::type, typename inner<_>::type, typename inner<_>::type>'}}
+using T2 = types<int, char, double, long>;
 using D2 = drop<4, int, char, double, long>::type;
 using D2 = types<>;
 
diff --git a/clang/test/Modules/submodules-merge-defs.cpp b/clang/test/Modules/submodules-merge-defs.cpp
index 23d1f5cfb12..4ab822a022b 100644
--- a/clang/test/Modules/submodules-merge-defs.cpp
+++ b/clang/test/Modules/submodules-merge-defs.cpp
@@ -58,6 +58,11 @@ G::A pre_ga // expected-error +{{must be imported}}
 decltype(G::h) pre_gh = G::h; // expected-error +{{must be imported}}
 // expected-note@defs.h:51 +{{here}}
 
+int pre_h = H(); // expected-error +{{must be imported}}
+// expected-note@defs.h:56 +{{here}}
+using pre_i = I<>; // expected-error +{{must be imported}}
+// expected-note@defs.h:57 +{{here}}
+
 J<> pre_j; // expected-error {{declaration of 'J' must be imported}}
 #ifdef IMPORT_USE_2
 // expected-error-re@-2 {{default argument of 'J' must be imported from one of {{.*}}stuff.use{{.*}}stuff.use-2}}
@@ -99,6 +104,8 @@ int post_ff = F<char>().f();
 int post_fg = F<char>().g<int>();
 G::A post_ga = G::a;
 decltype(G::h) post_gh = G::h;
+int post_h = H();
+using post_i = I<>;
 J<> post_j;
 template<typename T, int N, template<typename> class K> struct J;
 J<> post_j2;
diff --git a/clang/test/SemaCXX/alias-template.cpp b/clang/test/SemaCXX/alias-template.cpp
index bcfe428c69d..b6256103ef8 100644
--- a/clang/test/SemaCXX/alias-template.cpp
+++ b/clang/test/SemaCXX/alias-template.cpp
@@ -35,8 +35,8 @@ namespace VariableLengthArrays {
   template<typename Z> using T = int[n]; // expected-error {{variable length array declaration not allowed at file scope}}
 
   const int m = 42;
-  template<typename Z> using U = int[m]; // expected-note {{previous definition}}
-  template<typename Z> using U = int[42]; // ok
+  template<typename Z> using U = int[m];
+  template<typename Z> using U = int[42]; // expected-note {{previous definition}} 
   template<typename Z> using U = int; // expected-error {{type alias template redefinition with different types ('int' vs 'int [42]')}}
 }
 
diff --git a/clang/test/SemaTemplate/alias-templates.cpp b/clang/test/SemaTemplate/alias-templates.cpp
index 1849ff64026..b7078353ff1 100644
--- a/clang/test/SemaTemplate/alias-templates.cpp
+++ b/clang/test/SemaTemplate/alias-templates.cpp
@@ -221,3 +221,9 @@ namespace PR14858 {
   template<typename ...T, typename ...U> void h(X<T...> &) {}
   template<typename ...T, typename ...U> void h(X<U...> &) {} // ok, different
 }
+
+namespace redecl {
+  template<typename> using A = int;
+  template<typename = void> using A = int;
+  A<> a; // ok
+}