Revert "[clang] Fix missing diagnostic of declaration use when access…

…ing TypeDecls through typename access"

This reverts commit dc17043.
Breaks building LLVM on mac when targeting macOS before 10.15, see
comments on https://reviews.llvm.org/D136533

clang/docs/ReleaseNotes.rst

@@ -255,9 +255,6 @@ Bug Fixes
 - Reject non-type template arguments formed by casting a non-zero integer
   to a pointer in pre-C++17 modes, instead of treating them as null
   pointers.
-- Fix missing diagnostics for uses of declarations when performing typename access,
-  such as when performing member access on a '[[deprecated]]' type alias.
-  `Issue 58547 <https://github.com/llvm/llvm-project/issues/58547>`
 
 Improvements to Clang's diagnostics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

clang/include/clang/Sema/Sema.h

@@ -2566,10 +2566,6 @@ class Sema final {
 
   bool isSimpleTypeSpecifier(tok::TokenKind Kind) const;
 
-  enum class DiagCtorKind { None, Implicit, Typename };
-  QualType getTypeDeclType(DeclContext *LookupCtx, DiagCtorKind DCK,
-                           TypeDecl *TD, SourceLocation NameLoc);
-
   ParsedType getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
                          Scope *S, CXXScopeSpec *SS = nullptr,
                          bool isClassName = false, bool HasTrailingDot = false,

clang/lib/Sema/SemaDecl.cpp

@@ -169,26 +169,6 @@ bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const {
   return false;
 }
 
-QualType Sema::getTypeDeclType(DeclContext *LookupCtx, DiagCtorKind DCK,
-                               TypeDecl *TD, SourceLocation NameLoc) {
-  auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx);
-  auto *FoundRD = dyn_cast<CXXRecordDecl>(TD);
-  if (DCK != DiagCtorKind::None && LookupRD && FoundRD &&
-      FoundRD->isInjectedClassName() &&
-      declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent()))) {
-    Diag(NameLoc,
-         DCK == DiagCtorKind::Typename
-             ? diag::ext_out_of_line_qualified_id_type_names_constructor
-             : diag::err_out_of_line_qualified_id_type_names_constructor)
-        << TD->getIdentifier() << /*Type*/ 1
-        << 0 /*if any keyword was present, it was 'typename'*/;
-  }
-
-  DiagnoseUseOfDecl(TD, NameLoc);
-  MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
-  return Context.getTypeDeclType(TD);
-}
-
 namespace {
 enum class UnqualifiedTypeNameLookupResult {
   NotFound,
@@ -352,11 +332,10 @@ ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
                              bool IsClassTemplateDeductionContext,
                              ImplicitTypenameContext AllowImplicitTypename,
                              IdentifierInfo **CorrectedII) {
-  bool IsImplicitTypename = !isClassName && !IsCtorOrDtorName;
   // FIXME: Consider allowing this outside C++1z mode as an extension.
   bool AllowDeducedTemplate = IsClassTemplateDeductionContext &&
-                              getLangOpts().CPlusPlus17 && IsImplicitTypename &&
-                              !HasTrailingDot;
+                              getLangOpts().CPlusPlus17 && !IsCtorOrDtorName &&
+                              !isClassName && !HasTrailingDot;
 
   // Determine where we will perform name lookup.
   DeclContext *LookupCtx = nullptr;
@@ -380,9 +359,11 @@ ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
         // refer to a member of an unknown specialization.
         // In C++2a, in several contexts a 'typename' is not required. Also
         // allow this as an extension.
+        if (AllowImplicitTypename == ImplicitTypenameContext::No &&
+            !isClassName && !IsCtorOrDtorName)
+          return nullptr;
+        bool IsImplicitTypename = !isClassName && !IsCtorOrDtorName;
         if (IsImplicitTypename) {
-          if (AllowImplicitTypename == ImplicitTypenameContext::No)
-            return nullptr;
           SourceLocation QualifiedLoc = SS->getRange().getBegin();
           if (getLangOpts().CPlusPlus20)
             Diag(QualifiedLoc, diag::warn_cxx17_compat_implicit_typename);
@@ -556,10 +537,18 @@ ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
     // C++ [class.qual]p2: A lookup that would find the injected-class-name
     // instead names the constructors of the class, except when naming a class.
     // This is ill-formed when we're not actually forming a ctor or dtor name.
-    T = getTypeDeclType(LookupCtx,
-                        IsImplicitTypename ? DiagCtorKind::Implicit
-                                           : DiagCtorKind::None,
-                        TD, NameLoc);
+    auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx);
+    auto *FoundRD = dyn_cast<CXXRecordDecl>(TD);
+    if (!isClassName && !IsCtorOrDtorName && LookupRD && FoundRD &&
+        FoundRD->isInjectedClassName() &&
+        declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent())))
+      Diag(NameLoc, diag::err_out_of_line_qualified_id_type_names_constructor)
+          << &II << /*Type*/1;
+
+    DiagnoseUseOfDecl(IIDecl, NameLoc);
+
+    T = Context.getTypeDeclType(TD);
+    MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
   } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
     (void)DiagnoseUseOfDecl(IDecl, NameLoc);
     if (!HasTrailingDot)

clang/lib/Sema/SemaTemplate.cpp

@@ -10963,14 +10963,20 @@ Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword,
       //
       // FIXME: That's not strictly true: mem-initializer-id lookup does not
       // ignore functions, but that appears to be an oversight.
-      QualType T = getTypeDeclType(
-          Ctx,
-          Keyword == ETK_Typename ? DiagCtorKind::Typename : DiagCtorKind::None,
-          Type, IILoc);
+      auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(Ctx);
+      auto *FoundRD = dyn_cast<CXXRecordDecl>(Type);
+      if (Keyword == ETK_Typename && LookupRD && FoundRD &&
+          FoundRD->isInjectedClassName() &&
+          declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent())))
+        Diag(IILoc, diag::ext_out_of_line_qualified_id_type_names_constructor)
+            << &II << 1 << 0 /*'typename' keyword used*/;
+
       // We found a type. Build an ElaboratedType, since the
       // typename-specifier was just sugar.
-      return Context.getElaboratedType(
-          Keyword, QualifierLoc.getNestedNameSpecifier(), T);
+      MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
+      return Context.getElaboratedType(Keyword,
+                                       QualifierLoc.getNestedNameSpecifier(),
+                                       Context.getTypeDeclType(Type));
     }
 
     // C++ [dcl.type.simple]p2:

clang/test/CXX/dcl.dcl/dcl.attr/dcl.attr.deprecated/p1.cpp

@@ -58,17 +58,3 @@ template <typename T>
   FunS2 f;// No warning, entire function is deprecated, so usage here should be fine.
 
 }
-
-namespace GH58547 {
-struct A {
-  using ta [[deprecated]] = int; // expected-note 2{{marked deprecated here}}
-};
-
-using t1 = typename A::ta; // expected-warning {{'ta' is deprecated}}
-
-template <class B1> struct B {
-  using tb = typename B1::ta; // expected-warning {{'ta' is deprecated}}
-};
-
-template struct B<A>; // expected-note {{requested here}}
-} // namespace GH58547

libcxx/test/libcxx/depr/depr.default.allocator/allocator.members/allocate.depr_in_cxx17.verify.cpp

@@ -13,8 +13,7 @@
 
 // Deprecated in C++17
 
-// FIXME: Remove 'clang-16' from UNSUPPORTED by 2022-11-05 (bugfix D136533).
-// UNSUPPORTED: c++03, c++11, c++14, clang-16
+// UNSUPPORTED: c++03, c++11, c++14
 
 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS
 
@@ -24,11 +23,7 @@
 int main(int, char**)
 {
     std::allocator<int> a;
-    TEST_IGNORE_NODISCARD a.allocate(3, nullptr);
-    // expected-warning@-1 {{'allocate' is deprecated}}
-#if defined(TEST_CLANG_VER) && TEST_CLANG_VER >= 1600
-    // expected-warning@*:* {{'pointer' is deprecated}}
-    // expected-warning@*:* {{'const_pointer' is deprecated}}
-#endif
+    TEST_IGNORE_NODISCARD a.allocate(3, nullptr); // expected-warning {{'allocate' is deprecated}}
+
     return 0;
 }