[FOLD] return most recent declaration of primary

Author: sdkrystian

clang/include/clang/AST/DeclTemplate.h

@@ -1955,13 +1955,7 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
   /// specialization which was specialized by this.
   llvm::PointerUnion<ClassTemplateDecl *,
                      ClassTemplatePartialSpecializationDecl *>
-  getSpecializedTemplateOrPartial() const {
-    if (const auto *PartialSpec =
-            SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
-      return PartialSpec->PartialSpecialization;
-
-    return SpecializedTemplate.get<ClassTemplateDecl*>();
-  }
+  getSpecializedTemplateOrPartial() const;
 
   /// Retrieve the set of template arguments that should be used
   /// to instantiate members of the class template or class template partial
@@ -2713,13 +2707,7 @@ class VarTemplateSpecializationDecl : public VarDecl,
   /// Retrieve the variable template or variable template partial
   /// specialization which was specialized by this.
   llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
-  getSpecializedTemplateOrPartial() const {
-    if (const auto *PartialSpec =
-            SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
-      return PartialSpec->PartialSpecialization;
-
-    return SpecializedTemplate.get<VarTemplateDecl *>();
-  }
+  getSpecializedTemplateOrPartial() const;
 
   /// Retrieve the set of template arguments that should be used
   /// to instantiate the initializer of the variable template or variable

clang/lib/AST/Decl.cpp

@@ -4159,7 +4159,7 @@ FunctionTemplateDecl *FunctionDecl::getPrimaryTemplate() const {
   if (FunctionTemplateSpecializationInfo *Info
         = TemplateOrSpecialization
             .dyn_cast<FunctionTemplateSpecializationInfo*>()) {
-    return Info->getTemplate();
+    return Info->getTemplate()->getMostRecentDecl();
   }
   return nullptr;
 }

clang/lib/AST/DeclTemplate.cpp

@@ -997,12 +997,23 @@ void ClassTemplateSpecializationDecl::getNameForDiagnostic(
   }
 }
 
+llvm::PointerUnion<ClassTemplateDecl *,
+                   ClassTemplatePartialSpecializationDecl *>
+ClassTemplateSpecializationDecl::getSpecializedTemplateOrPartial() const {
+  if (const auto *PartialSpec =
+          SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
+    return PartialSpec->PartialSpecialization->getMostRecentDecl();
+
+  return SpecializedTemplate.get<ClassTemplateDecl *>()->getMostRecentDecl();
+}
+
 ClassTemplateDecl *
 ClassTemplateSpecializationDecl::getSpecializedTemplate() const {
   if (const auto *PartialSpec =
           SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization*>())
-    return PartialSpec->PartialSpecialization->getSpecializedTemplate();
-  return SpecializedTemplate.get<ClassTemplateDecl*>();
+    return PartialSpec->PartialSpecialization->getSpecializedTemplate()
+        ->getMostRecentDecl();
+  return SpecializedTemplate.get<ClassTemplateDecl *>()->getMostRecentDecl();
 }
 
 SourceRange
@@ -1410,11 +1421,21 @@ void VarTemplateSpecializationDecl::getNameForDiagnostic(
   }
 }
 
+llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
+VarTemplateSpecializationDecl::getSpecializedTemplateOrPartial() const {
+  if (const auto *PartialSpec =
+          SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
+    return PartialSpec->PartialSpecialization->getMostRecentDecl();
+
+  return SpecializedTemplate.get<VarTemplateDecl *>()->getMostRecentDecl();
+}
+
 VarTemplateDecl *VarTemplateSpecializationDecl::getSpecializedTemplate() const {
   if (const auto *PartialSpec =
           SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
-    return PartialSpec->PartialSpecialization->getSpecializedTemplate();
-  return SpecializedTemplate.get<VarTemplateDecl *>();
+    return PartialSpec->PartialSpecialization->getSpecializedTemplate()
+        ->getMostRecentDecl();
+  return SpecializedTemplate.get<VarTemplateDecl *>()->getMostRecentDecl();
 }
 
 SourceRange VarTemplateSpecializationDecl::getSourceRange() const {

clang/test/AST/ast-dump-decl.cpp

@@ -530,7 +530,7 @@ namespace testCanonicalTemplate {
   // CHECK-NEXT: |   `-ClassTemplateDecl 0x{{.+}} parent 0x{{.+}} <col:5, col:40> col:40 friend_undeclared TestClassTemplate{{$}}
   // CHECK-NEXT: |     |-TemplateTypeParmDecl 0x{{.+}} <col:14, col:23> col:23 typename depth 1 index 0 T2{{$}}
   // CHECK-NEXT: |     `-CXXRecordDecl 0x{{.+}} parent 0x{{.+}} <col:34, col:40> col:40 class TestClassTemplate{{$}}
-  // CHECK-NEXT: `-ClassTemplateSpecializationDecl 0x{{.+}} <line:[[@LINE-19]]:3, line:[[@LINE-17]]:3> line:[[@LINE-19]]:31 class TestClassTemplate definition implicit_instantiation{{$}}
+  // CHECK-NEXT: `-ClassTemplateSpecializationDecl 0x{{.+}} <col:5, col:40> line:[[@LINE-19]]:31 class TestClassTemplate definition implicit_instantiation{{$}}
   // CHECK-NEXT:   |-DefinitionData pass_in_registers empty aggregate standard_layout trivially_copyable pod trivial literal has_constexpr_non_copy_move_ctor can_const_default_init{{$}}
   // CHECK-NEXT:   | |-DefaultConstructor exists trivial constexpr defaulted_is_constexpr{{$}}
   // CHECK-NEXT:   | |-CopyConstructor simple trivial has_const_param implicit_has_const_param{{$}}