[clang][Sema] Unwrap reference types in HeuristicResolverImpl::resolveTypeToRecordDecl()

Partially fixes #124450

Author: HighCommander4

clang/lib/Sema/HeuristicResolver.cpp

@@ -133,8 +133,8 @@ TemplateName getReferencedTemplateName(const Type *T) {
 CXXRecordDecl *HeuristicResolverImpl::resolveTypeToRecordDecl(const Type *T) {
   assert(T);
 
-  // Unwrap type sugar such as type aliases.
-  T = T->getCanonicalTypeInternal().getTypePtr();
+  // Unwrap references and type sugar such as type aliases.
+  T = T->getCanonicalTypeInternal().getNonReferenceType().getTypePtr();
 
   if (const auto *DNT = T->getAs<DependentNameType>()) {
     T = resolveDeclsToType(resolveDependentNameType(DNT), Ctx)

clang/unittests/Sema/HeuristicResolverTest.cpp

@@ -213,6 +213,27 @@ TEST(HeuristicResolver, MemberExpr_Chained) {
       cxxMethodDecl(hasName("foo")).bind("output"));
 }
 
+TEST(HeuristicResolver, MemberExpr_ReferenceType) {
+  std::string Code = R"cpp(
+    struct B {
+      int waldo;
+    };
+    template <typename T>
+    struct A {
+      B &b;
+    };
+    template <typename T>
+    void foo(A<T> &a) {
+      a.b.waldo;
+    }
+  )cpp";
+  // Test resolution of "waldo" in "a.b.waldo".
+  expectResolution(
+      Code, &HeuristicResolver::resolveMemberExpr,
+      cxxDependentScopeMemberExpr(hasMemberName("waldo")).bind("input"),
+      fieldDecl(hasName("waldo")).bind("output"));
+}
+
 TEST(HeuristicResolver, MemberExpr_TemplateArgs) {
   std::string Code = R"cpp(
     struct Foo {