Factor out a diagnostic kind enum for use in two %select expressions

NFC

llvm-svn: 283131

4 files changed, 40 insertions, 25 deletions

diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 94f31696ec5..74c4e41c473 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -1970,6 +1970,21 @@ public:
   Decl *BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
                                        RecordDecl *Record);
 
+  /// Common ways to introduce type names without a tag for use in diagnostics.
+  /// Keep in sync with err_tag_reference_non_tag.
+  enum NonTagKind {
+    NTK_Unknown,
+    NTK_Typedef,
+    NTK_TypeAlias,
+    NTK_Template,
+    NTK_TypeAliasTemplate,
+    NTK_TemplateTemplateArgument,
+  };
+
+  /// Given a non-tag type declaration, returns an enum useful for indicating
+  /// what kind of non-tag type this is.
+  NonTagKind getNonTagTypeDeclKind(const Decl *D);
+
   bool isAcceptableTagRedeclaration(const TagDecl *Previous,
                                     TagTypeKind NewTag, bool isDefinition,
                                     SourceLocation NewTagLoc,
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index d85a612e0b7..21778e8b62c 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -12243,6 +12243,20 @@ static bool isClassCompatTagKind(TagTypeKind Tag)
   return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
 }
 
+Sema::NonTagKind Sema::getNonTagTypeDeclKind(const Decl *PrevDecl) {
+  if (isa<TypedefDecl>(PrevDecl))
+    return NTK_Typedef;
+  else if (isa<TypeAliasDecl>(PrevDecl))
+    return NTK_TypeAlias;
+  else if (isa<ClassTemplateDecl>(PrevDecl))
+    return NTK_Template;
+  else if (isa<TypeAliasTemplateDecl>(PrevDecl))
+    return NTK_TypeAliasTemplate;
+  else if (isa<TemplateTemplateParmDecl>(PrevDecl))
+    return NTK_TemplateTemplateArgument;
+  return NTK_Unknown;
+}
+
 /// \brief Determine whether a tag with a given kind is acceptable
 /// as a redeclaration of the given tag declaration.
 ///
@@ -13023,11 +13037,8 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
       // (non-redeclaration) lookup.
       if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
           !Previous.isForRedeclaration()) {
-        unsigned Kind = 0;
-        if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
-        else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
-        else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
-        Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind;
+        NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl);
+        Diag(NameLoc, diag::err_tag_reference_non_tag) << NTK;
         Diag(PrevDecl->getLocation(), diag::note_declared_at);
         Invalid = true;
 
@@ -13038,11 +13049,8 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
 
       // Diagnose implicit declarations introduced by elaborated types.
       } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
-        unsigned Kind = 0;
-        if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
-        else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
-        else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
-        Diag(NameLoc, diag::err_tag_reference_conflict) << Kind;
+        NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl);
+        Diag(NameLoc, diag::err_tag_reference_conflict) << NTK;
         Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
         Invalid = true;
 
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index b1bb97b7586..7061f079ac7 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -2468,7 +2468,7 @@ TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
     //   If the identifier resolves to a typedef-name or the simple-template-id
     //   resolves to an alias template specialization, the
     //   elaborated-type-specifier is ill-formed.
-    Diag(TemplateLoc, diag::err_tag_reference_non_tag) << 4;
+    Diag(TemplateLoc, diag::err_tag_reference_non_tag) << NTK_TypeAliasTemplate;
     Diag(TAT->getLocation(), diag::note_declared_at);
   }
   
@@ -7438,14 +7438,8 @@ Sema::ActOnExplicitInstantiation(Scope *S,
   ClassTemplateDecl *ClassTemplate = dyn_cast<ClassTemplateDecl>(TD);
 
   if (!ClassTemplate) {
-    unsigned ErrorKind = 0;
-    if (isa<TypeAliasTemplateDecl>(TD)) {
-      ErrorKind = 4;
-    } else if (isa<TemplateTemplateParmDecl>(TD)) {
-      ErrorKind = 5;
-    }
-
-    Diag(TemplateNameLoc, diag::err_tag_reference_non_tag) << ErrorKind;
+    NonTagKind NTK = getNonTagTypeDeclKind(TD);
+    Diag(TemplateNameLoc, diag::err_tag_reference_non_tag) << NTK;
     Diag(TD->getLocation(), diag::note_previous_use);
     return true;
   }
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index ef3740b7177..a74171ed5f8 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -1013,11 +1013,8 @@ public:
         case LookupResult::FoundOverloaded:
         case LookupResult::FoundUnresolvedValue: {
           NamedDecl *SomeDecl = Result.getRepresentativeDecl();
-          unsigned Kind = 0;
-          if (isa<TypedefDecl>(SomeDecl)) Kind = 1;
-          else if (isa<TypeAliasDecl>(SomeDecl)) Kind = 2;
-          else if (isa<ClassTemplateDecl>(SomeDecl)) Kind = 3;
-          SemaRef.Diag(IdLoc, diag::err_tag_reference_non_tag) << Kind;
+          Sema::NonTagKind NTK = SemaRef.getNonTagTypeDeclKind(SomeDecl);
+          SemaRef.Diag(IdLoc, diag::err_tag_reference_non_tag) << NTK;
           SemaRef.Diag(SomeDecl->getLocation(), diag::note_declared_at);
           break;
         }
@@ -5703,7 +5700,8 @@ TreeTransform<Derived>::TransformElaboratedType(TypeLocBuilder &TLB,
       if (TypeAliasTemplateDecl *TAT = dyn_cast_or_null<TypeAliasTemplateDecl>(
               Template.getAsTemplateDecl())) {
         SemaRef.Diag(TL.getNamedTypeLoc().getBeginLoc(),
-                     diag::err_tag_reference_non_tag) << 4;
+                     diag::err_tag_reference_non_tag)
+            << Sema::NTK_TypeAliasTemplate;
         SemaRef.Diag(TAT->getLocation(), diag::note_declared_at);
       }
     }