PR26048, PR26050: put non-type template parameters and indirect field decls

into IDNS_Tag in C++, because they conflict with redeclarations of tags. (This
doesn't affect elaborated-type-specifier lookup, which looks for IDNS_Type in
C++).

llvm-svn: 256985

2 files changed, 18 insertions, 3 deletions

diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 42bebc543e3..797e07b4b78 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -4024,16 +4024,26 @@ EnumConstantDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
 
 void IndirectFieldDecl::anchor() { }
 
+IndirectFieldDecl::IndirectFieldDecl(ASTContext &C, DeclContext *DC,
+                                     SourceLocation L, DeclarationName N,
+                                     QualType T, NamedDecl **CH, unsigned CHS)
+    : ValueDecl(IndirectField, DC, L, N, T), Chaining(CH), ChainingSize(CHS) {
+  // In C++, indirect field declarations conflict with tag declarations in the
+  // same scope, so add them to IDNS_Tag so that tag redeclaration finds them.
+  if (C.getLangOpts().CPlusPlus)
+    IdentifierNamespace |= IDNS_Tag;
+}
+
 IndirectFieldDecl *
 IndirectFieldDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L,
                           IdentifierInfo *Id, QualType T, NamedDecl **CH,
                           unsigned CHS) {
-  return new (C, DC) IndirectFieldDecl(DC, L, Id, T, CH, CHS);
+  return new (C, DC) IndirectFieldDecl(C, DC, L, Id, T, CH, CHS);
 }
 
 IndirectFieldDecl *IndirectFieldDecl::CreateDeserialized(ASTContext &C,
                                                          unsigned ID) {
-  return new (C, ID) IndirectFieldDecl(nullptr, SourceLocation(),
+  return new (C, ID) IndirectFieldDecl(C, nullptr, SourceLocation(),
                                        DeclarationName(), QualType(), nullptr,
                                        0);
 }
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 16394e865eb..72587e388e4 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -569,7 +569,6 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case Var:
     case ImplicitParam:
     case ParmVar:
-    case NonTypeTemplateParm:
     case ObjCMethod:
     case ObjCProperty:
     case MSProperty:
@@ -579,6 +578,12 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case IndirectField:
       return IDNS_Ordinary | IDNS_Member;
 
+    case NonTypeTemplateParm:
+      // Non-type template parameters are not found by lookups that ignore
+      // non-types, but they are found by redeclaration lookups for tag types,
+      // so we include them in the tag namespace.
+      return IDNS_Ordinary | IDNS_Tag;
+
     case ObjCCompatibleAlias:
     case ObjCInterface:
       return IDNS_Ordinary | IDNS_Type;