diff --git a/toolchain/check/cpp/generate_ast.cpp b/toolchain/check/cpp/generate_ast.cpp
index b8df6bf28b26..c62b4bd1b0a2 100644
--- a/toolchain/check/cpp/generate_ast.cpp
+++ b/toolchain/check/cpp/generate_ast.cpp
@@ -355,6 +355,9 @@ class CarbonExternalASTSource : public clang::ExternalASTSource {
   auto MapInstIdToClangDeclOrType(LookupResult lookup)
       -> std::variant<clang::NamedDecl*, clang::QualType>;
 
+  auto GetOrExportFunctionToCpp(SemIR::InstId target_inst_id,
+                                SemIR::FunctionId function_id)
+      -> clang::FunctionDecl*;
   // Get a current best-effort location for the current position within C++
   // processing.
   auto GetCurrentCppLocId() -> SemIR::LocId {
@@ -426,15 +429,8 @@ auto CarbonExternalASTSource::MapInstIdToClangDeclOrType(LookupResult lookup)
         return nullptr;
       }
 
-      const SemIR::Function& function =
-          context_->functions().Get(callee_function->function_id);
-      if (function.clang_decl_id.has_value()) {
-        return cast<clang::NamedDecl>(
-            context_->clang_decls().Get(function.clang_decl_id).key.decl);
-      }
-
-      return ExportFunctionToCpp(*context_, SemIR::LocId(target_inst_id),
-                                 callee_function->function_id);
+      return GetOrExportFunctionToCpp(target_inst_id,
+                                      callee_function->function_id);
     }
     case CARBON_KIND(SemIR::FieldDecl field_decl): {
       return ExportFieldToCpp(*context_, target_inst_id, field_decl);
@@ -444,6 +440,19 @@ auto CarbonExternalASTSource::MapInstIdToClangDeclOrType(LookupResult lookup)
   }
 }
 
+auto CarbonExternalASTSource::GetOrExportFunctionToCpp(
+    SemIR::InstId target_inst_id, SemIR::FunctionId function_id)
+    -> clang::FunctionDecl* {
+  const SemIR::Function& function = context_->functions().Get(function_id);
+  if (function.clang_decl_id.has_value()) {
+    return cast<clang::FunctionDecl>(
+        context_->clang_decls().Get(function.clang_decl_id).key.decl);
+  }
+
+  return ExportFunctionToCpp(*context_, SemIR::LocId(target_inst_id),
+                             function_id);
+}
+
 auto CarbonExternalASTSource::BuildCarbonNamespace() -> void {
   static const llvm::StringLiteral carbon_namespace_name = "Carbon";
   auto& ast_context = context_->ast_context();
@@ -653,6 +662,33 @@ auto CarbonExternalASTSource::CompleteType(clang::TagDecl* tag_decl) -> void {
   class_decl->addDecl(ExportDestructorToCpp(*context_, class_info, class_decl));
 
   // TODO: Import any special member functions that affect class properties.
+
+  if (class_info.vtable_decl_id.has_value()) {
+    auto vtable_inst_block = context_->inst_blocks().Get(
+        context_->vtables()
+            .Get(context_->insts()
+                     .GetAs<SemIR::VtableDecl>(class_info.vtable_decl_id)
+                     .vtable_id)
+            .virtual_functions_id);
+    for (auto vtable_entry_id : vtable_inst_block) {
+      if (!vtable_entry_id.has_value()) {
+        continue;
+      }
+
+      auto callee_function =
+          GetCalleeAsFunction(context_->sem_ir(), vtable_entry_id);
+      const SemIR::Function& function =
+          context_->functions().Get(callee_function.function_id);
+
+      // If this is a member of a base class, nothing to do here.
+      if (function.parent_scope_id != class_info.scope_id) {
+        continue;
+      }
+      auto* method_decl = cast<clang::CXXMethodDecl>(GetOrExportFunctionToCpp(
+          vtable_entry_id, callee_function.function_id));
+      context_->clang_sema().AddOverriddenMethods(class_decl, method_decl);
+    }
+  }
   class_decl->completeDefinition();
 }
 
diff --git a/toolchain/check/testdata/interop/cpp/class/export/base.carbon b/toolchain/check/testdata/interop/cpp/class/export/base.carbon
index 2e6b4b48ed01..d28a56cf51ee 100644
--- a/toolchain/check/testdata/interop/cpp/class/export/base.carbon
+++ b/toolchain/check/testdata/interop/cpp/class/export/base.carbon
@@ -133,6 +133,16 @@ import Cpp;
 // CHECK:STDERR: ^~~~~~~~~~~~~~~~~~~~~~~~~
 // CHECK:STDERR:
 abstract class Abstract {
+  // CHECK:STDERR: fail_todo_abstract_nonvirtual_dtor_but_virtual_fns.carbon:[[@LINE+10]]:3: error: initialization of abstract type `Abstract` [AbstractTypeInInit]
+  // CHECK:STDERR:   abstract fn F[self: Self]();
+  // CHECK:STDERR:   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
+  // CHECK:STDERR: fail_todo_abstract_nonvirtual_dtor_but_virtual_fns.carbon:[[@LINE-4]]:1: note: class was declared abstract here [ClassAbstractHere]
+  // CHECK:STDERR: abstract class Abstract {
+  // CHECK:STDERR: ^~~~~~~~~~~~~~~~~~~~~~~~~
+  // CHECK:STDERR: fail_todo_abstract_nonvirtual_dtor_but_virtual_fns.carbon:[[@LINE+4]]:17: note: initializing function parameter [InCallToFunctionParam]
+  // CHECK:STDERR:   abstract fn F[self: Self]();
+  // CHECK:STDERR:                 ^~~~~~~~~~
+  // CHECK:STDERR:
   abstract fn F[self: Self]();
 }
 
diff --git a/toolchain/lower/testdata/interop/cpp/class/import/dynamic.carbon b/toolchain/lower/testdata/interop/cpp/class/import/dynamic.carbon
index 0cb07add47a2..2b2bca3db762 100644
--- a/toolchain/lower/testdata/interop/cpp/class/import/dynamic.carbon
+++ b/toolchain/lower/testdata/interop/cpp/class/import/dynamic.carbon
@@ -19,31 +19,26 @@ import Cpp;
 inline Cpp '''
 
 struct FurtherBase {
-  virtual auto further_base_func() -> int {
-    return 11;
-  }
+  virtual auto further_base_func() -> void;
 };
 
 struct Base: FurtherBase {
   int i;
-  virtual auto func() -> int {
-    return 7;
-  }
+  virtual auto func() & -> void;
 };
 
-auto Use(Base& b) -> int {
-  return b.func();
+__attribute__((optnone)) auto Use(Base& b) {
 }
 
 ''';
 
 base class Derived {
   extend base: Cpp.Base;
-  // TODO: `other_func` should appear in the vtable (it currently
-  // doesn't because the CXXRecordDecl we export has no CXXMethodDecl
-  // children - those need to be added, and in the right order)
-  virtual fn other_func[unused self: Self]() -> i32 {
-    return 3;
+  // TODO: `other_func` should appear in the vtable (it currently doesn't
+  // maybe because the CXXMethodDecl isn't marked as virtual)
+  virtual fn other_func[unused self: Self]() {
+  }
+  override fn func[unused ref self: Self]() {
   }
 }
 
@@ -56,9 +51,9 @@ void WorkaroundToEmitCtorAndVtable() {
 
 // TODO: Carbon lowering should emit initialization that refers to the
 // Clang-lowered vtable.
-auto DoThing() -> int {
+auto DoThing() -> void {
   Carbon::Derived d;
-  return Use(d);
+  Use(d);
 }
 
 ''';
@@ -76,10 +71,6 @@ auto DoThing() -> int {
 // CHECK:STDOUT:
 // CHECK:STDOUT: $_ZN6Carbon7DerivedD2Ev = comdat any
 // CHECK:STDOUT:
-// CHECK:STDOUT: $_ZN11FurtherBase17further_base_funcEv = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZN4Base4funcEv = comdat any
-// CHECK:STDOUT:
 // CHECK:STDOUT: $_ZN4BaseC2Ev = comdat any
 // CHECK:STDOUT:
 // CHECK:STDOUT: $_ZN11FurtherBaseC2Ev = comdat any
@@ -90,51 +81,31 @@ auto DoThing() -> int {
 // CHECK:STDOUT:
 // CHECK:STDOUT: $_ZTSN6Carbon7DerivedE = comdat any
 // CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTI4Base = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTS4Base = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTI11FurtherBase = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTS11FurtherBase = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTV4Base = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: $_ZTV11FurtherBase = comdat any
-// CHECK:STDOUT:
-// CHECK:STDOUT: @_ZTVN6Carbon7DerivedE = linkonce_odr dso_local unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr @_ZTIN6Carbon7DerivedE, ptr @_ZN11FurtherBase17further_base_funcEv, ptr @_ZN4Base4funcEv] }, comdat, align 8
+// CHECK:STDOUT: @_ZTVN6Carbon7DerivedE = linkonce_odr dso_local unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr @_ZTIN6Carbon7DerivedE, ptr @_ZN11FurtherBase17further_base_funcEv, ptr @_ZNR6Carbon7Derived4funcEv] }, comdat, align 8
 // CHECK:STDOUT: @_ZTIN6Carbon7DerivedE = linkonce_odr dso_local constant { ptr, ptr, ptr } { ptr getelementptr inbounds (ptr, ptr @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr @_ZTSN6Carbon7DerivedE, ptr @_ZTI4Base }, comdat, align 8
 // CHECK:STDOUT: @_ZTVN10__cxxabiv120__si_class_type_infoE = external global [0 x ptr]
 // CHECK:STDOUT: @_ZTSN6Carbon7DerivedE = linkonce_odr dso_local constant [18 x i8] c"N6Carbon7DerivedE\00", comdat, align 1
-// CHECK:STDOUT: @_ZTI4Base = linkonce_odr dso_local constant { ptr, ptr, ptr } { ptr getelementptr inbounds (ptr, ptr @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), ptr @_ZTS4Base, ptr @_ZTI11FurtherBase }, comdat, align 8
-// CHECK:STDOUT: @_ZTS4Base = linkonce_odr dso_local constant [6 x i8] c"4Base\00", comdat, align 1
-// CHECK:STDOUT: @_ZTI11FurtherBase = linkonce_odr dso_local constant { ptr, ptr } { ptr getelementptr inbounds (ptr, ptr @_ZTVN10__cxxabiv117__class_type_infoE, i64 2), ptr @_ZTS11FurtherBase }, comdat, align 8
-// CHECK:STDOUT: @_ZTVN10__cxxabiv117__class_type_infoE = external global [0 x ptr]
-// CHECK:STDOUT: @_ZTS11FurtherBase = linkonce_odr dso_local constant [14 x i8] c"11FurtherBase\00", comdat, align 1
-// CHECK:STDOUT: @_ZTV4Base = linkonce_odr dso_local unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr @_ZTI4Base, ptr @_ZN11FurtherBase17further_base_funcEv, ptr @_ZN4Base4funcEv] }, comdat, align 8
-// CHECK:STDOUT: @_ZTV11FurtherBase = linkonce_odr dso_local unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr @_ZTI11FurtherBase, ptr @_ZN11FurtherBase17further_base_funcEv] }, comdat, align 8
+// CHECK:STDOUT: @_ZTI4Base = external constant ptr
+// CHECK:STDOUT: @_ZTV4Base = available_externally unnamed_addr constant { [4 x ptr] } { [4 x ptr] [ptr null, ptr @_ZTI4Base, ptr @_ZN11FurtherBase17further_base_funcEv, ptr @_ZNR4Base4funcEv] }, align 8
+// CHECK:STDOUT: @_ZTV11FurtherBase = available_externally unnamed_addr constant { [3 x ptr] } { [3 x ptr] [ptr null, ptr @_ZTI11FurtherBase, ptr @_ZN11FurtherBase17further_base_funcEv] }, align 8
+// CHECK:STDOUT: @_ZTI11FurtherBase = external constant ptr
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: mustprogress uwtable
-// CHECK:STDOUT: define dso_local noundef i32 @_Z3UseR4Base(ptr noundef nonnull align 8 dereferenceable(12) %b) #0 {
+// CHECK:STDOUT: ; Function Attrs: mustprogress noinline nounwind optnone uwtable
+// CHECK:STDOUT: define dso_local void @_Z3UseR4Base(ptr noundef nonnull align 8 dereferenceable(12) %b) #0 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %b.addr = alloca ptr, align 8
 // CHECK:STDOUT:   store ptr %b, ptr %b.addr, align 8, !tbaa !11
-// CHECK:STDOUT:   %0 = load ptr, ptr %b.addr, align 8, !tbaa !11, !nonnull !14, !align !15
-// CHECK:STDOUT:   %vtable = load ptr, ptr %0, align 8, !tbaa !16
-// CHECK:STDOUT:   %vfn = getelementptr inbounds ptr, ptr %vtable, i64 1
-// CHECK:STDOUT:   %1 = load ptr, ptr %vfn, align 8
-// CHECK:STDOUT:   %call = call noundef i32 %1(ptr noundef nonnull align 8 dereferenceable(12) %0)
-// CHECK:STDOUT:   ret i32 %call
+// CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
 // CHECK:STDOUT: define dso_local void @_Z29WorkaroundToEmitCtorAndVtablev() #1 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %d = alloca %"class.Carbon::Derived", align 8
-// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %d) #4
-// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %d) #4
-// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %d) #4
-// CHECK:STDOUT:   call void @llvm.lifetime.end.p0(ptr %d) #4
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %d) #5
+// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %d) #5
+// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %d) #5
+// CHECK:STDOUT:   call void @llvm.lifetime.end.p0(ptr %d) #5
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -145,9 +116,9 @@ auto DoThing() -> int {
 // CHECK:STDOUT: define linkonce_odr dso_local void @_ZN6Carbon7DerivedC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %this) unnamed_addr #3 comdat align 2 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %this.addr = alloca ptr, align 8
-// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !18
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !14
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
-// CHECK:STDOUT:   call void @_ZN4BaseC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %this1) #4
+// CHECK:STDOUT:   call void @_ZN4BaseC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %this1) #5
 // CHECK:STDOUT:   store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTVN6Carbon7DerivedE, i32 0, i32 0, i32 2), ptr %this1, align 8, !tbaa !16
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
@@ -156,7 +127,7 @@ auto DoThing() -> int {
 // CHECK:STDOUT: define linkonce_odr dso_local void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %this) unnamed_addr #3 comdat align 2 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %this.addr = alloca ptr, align 8
-// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !18
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !14
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
 // CHECK:STDOUT:   store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTVN6Carbon7DerivedE, i32 0, i32 0, i32 2), ptr %this1, align 8, !tbaa !16
 // CHECK:STDOUT:   call void @"_C__destroy_thunk:thunk.Derived.Main"(ptr noundef nonnull align 8 dereferenceable(12) %this1)
@@ -166,123 +137,120 @@ auto DoThing() -> int {
 // CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
 // CHECK:STDOUT: declare void @llvm.lifetime.end.p0(ptr captures(none)) #2
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: mustprogress uwtable
-// CHECK:STDOUT: define dso_local noundef i32 @_Z7DoThingv() #0 personality ptr @__gxx_personality_v0 {
+// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
+// CHECK:STDOUT: define dso_local void @_Z7DoThingv() #1 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %d = alloca %"class.Carbon::Derived", align 8
-// CHECK:STDOUT:   %exn.slot = alloca ptr, align 8
-// CHECK:STDOUT:   %ehselector.slot = alloca i32, align 4
-// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %d) #4
-// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %d) #4
-// CHECK:STDOUT:   %call = invoke noundef i32 @_Z3UseR4Base(ptr noundef nonnull align 8 dereferenceable(12) %d)
-// CHECK:STDOUT:           to label %invoke.cont unwind label %lpad
-// CHECK:STDOUT:
-// CHECK:STDOUT: invoke.cont:                                      ; preds = %entry
-// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %d) #4
-// CHECK:STDOUT:   call void @llvm.lifetime.end.p0(ptr %d) #4
-// CHECK:STDOUT:   ret i32 %call
-// CHECK:STDOUT:
-// CHECK:STDOUT: lpad:                                             ; preds = %entry
-// CHECK:STDOUT:   %0 = landingpad { ptr, i32 }
-// CHECK:STDOUT:           cleanup
-// CHECK:STDOUT:   %1 = extractvalue { ptr, i32 } %0, 0
-// CHECK:STDOUT:   store ptr %1, ptr %exn.slot, align 8
-// CHECK:STDOUT:   %2 = extractvalue { ptr, i32 } %0, 1
-// CHECK:STDOUT:   store i32 %2, ptr %ehselector.slot, align 4
-// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %d) #4
-// CHECK:STDOUT:   call void @llvm.lifetime.end.p0(ptr %d) #4
-// CHECK:STDOUT:   br label %eh.resume
-// CHECK:STDOUT:
-// CHECK:STDOUT: eh.resume:                                        ; preds = %lpad
-// CHECK:STDOUT:   %exn = load ptr, ptr %exn.slot, align 8
-// CHECK:STDOUT:   %sel = load i32, ptr %ehselector.slot, align 4
-// CHECK:STDOUT:   %lpad.val = insertvalue { ptr, i32 } poison, ptr %exn, 0
-// CHECK:STDOUT:   %lpad.val1 = insertvalue { ptr, i32 } %lpad.val, i32 %sel, 1
-// CHECK:STDOUT:   resume { ptr, i32 } %lpad.val1
-// CHECK:STDOUT:
-// CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT:   uselistorder ptr %d, { 0, 2, 1, 3, 4, 5, 6 }
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %d) #5
+// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %d) #5
+// CHECK:STDOUT:   call void @_Z3UseR4Base(ptr noundef nonnull align 8 dereferenceable(12) %d)
+// CHECK:STDOUT:   call void @_ZN6Carbon7DerivedD2Ev(ptr noundef nonnull align 8 dead_on_return(12) dereferenceable(12) %d) #5
+// CHECK:STDOUT:   call void @llvm.lifetime.end.p0(ptr %d) #5
+// CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: declare i32 @__gxx_personality_v0(...)
+// CHECK:STDOUT: declare void @_ZN11FurtherBase17further_base_funcEv(ptr noundef nonnull align 8 dereferenceable(8)) unnamed_addr #4
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
-// CHECK:STDOUT: define linkonce_odr dso_local noundef i32 @_ZN11FurtherBase17further_base_funcEv(ptr noundef nonnull align 8 dereferenceable(8) %this) unnamed_addr #1 comdat align 2 {
-// CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
-// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !20
-// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
-// CHECK:STDOUT:   ret i32 11
-// CHECK:STDOUT: }
+// CHECK:STDOUT: declare void @_ZNR4Base4funcEv(ptr noundef nonnull align 8 dereferenceable(12)) unnamed_addr #4
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
-// CHECK:STDOUT: define linkonce_odr dso_local noundef i32 @_ZN4Base4funcEv(ptr noundef nonnull align 8 dereferenceable(12) %this) unnamed_addr #1 comdat align 2 {
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_Cother_func.Derived.Main(ptr %self) #5 !dbg !18 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
-// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !11
-// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
-// CHECK:STDOUT:   ret i32 7
+// CHECK:STDOUT:   ret void, !dbg !24
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define i32 @_Cother_func.Derived.Main(ptr %self) #4 !dbg !22 {
+// CHECK:STDOUT: define void @_Cfunc.Derived.Main(ptr %self) #5 !dbg !25 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   ret i32 3, !dbg !29
+// CHECK:STDOUT:   ret void, !dbg !28
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_C__destroy_thunk:thunk.Derived.Main"(ptr %self) #5 !dbg !30 {
+// CHECK:STDOUT: define void @"_C__destroy_thunk:thunk.Derived.Main"(ptr %self) #6 !dbg !29 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   call void @"_COp.12e0d0434542305a:core.Destroy.Core"(ptr %self), !dbg !35
-// CHECK:STDOUT:   ret void, !dbg !35
+// CHECK:STDOUT:   call void @"_COp.12e0d0434542305a:core.Destroy.Core"(ptr %self), !dbg !32
+// CHECK:STDOUT:   ret void, !dbg !32
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.bfe31446004e2b71:core.Destroy.Core"(ptr %self) #4 !dbg !36 {
+// CHECK:STDOUT: define weak_odr void @"_COp.bfe31446004e2b71:core.Destroy.Core"(ptr %self) #5 !dbg !33 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   ret void, !dbg !39
+// CHECK:STDOUT:   ret void, !dbg !36
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.12e0d0434542305a:core.Destroy.Core"(ptr %self) #4 !dbg !40 {
+// CHECK:STDOUT: define weak_odr void @"_COp.12e0d0434542305a:core.Destroy.Core"(ptr %self) #5 !dbg !37 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   ret void, !dbg !43
+// CHECK:STDOUT:   ret void, !dbg !40
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_Cfunc__carbon_thunk.Derived.Main(ptr %self) #5 !dbg !41 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %Derived.func.call.vtable = load ptr, ptr %self, align 8, !dbg !44
+// CHECK:STDOUT:   %Derived.func.call = call ptr @llvm.load.relative.i32(ptr %Derived.func.call.vtable, i32 4), !dbg !44
+// CHECK:STDOUT:   call void %Derived.func.call(ptr %self), !dbg !44
+// CHECK:STDOUT:   ret void, !dbg !44
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_Cother_func__carbon_thunk.Derived.Main(ptr %self) #5 !dbg !45 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %Derived.other_func.call.vtable = load ptr, ptr %self, align 8, !dbg !48
+// CHECK:STDOUT:   %Derived.other_func.call = call ptr @llvm.load.relative.i32(ptr %Derived.other_func.call.vtable, i32 8), !dbg !48
+// CHECK:STDOUT:   call void %Derived.other_func.call(ptr %self), !dbg !48
+// CHECK:STDOUT:   ret void, !dbg !48
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: read)
+// CHECK:STDOUT: declare ptr @llvm.load.relative.i32(ptr, i32) #7
+// CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: inlinehint mustprogress nounwind uwtable
 // CHECK:STDOUT: define linkonce_odr dso_local void @_ZN4BaseC2Ev(ptr noundef nonnull align 8 dereferenceable(12) %this) unnamed_addr #3 comdat align 2 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %this.addr = alloca ptr, align 8
 // CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !11
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
-// CHECK:STDOUT:   call void @_ZN11FurtherBaseC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %this1) #4
+// CHECK:STDOUT:   call void @_ZN11FurtherBaseC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %this1) #5
 // CHECK:STDOUT:   store ptr getelementptr inbounds inrange(-16, 16) ({ [4 x ptr] }, ptr @_ZTV4Base, i32 0, i32 0, i32 2), ptr %this1, align 8, !tbaa !16
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZNR6Carbon7Derived4funcEv(ptr noundef nonnull align 8 dereferenceable(12) %this) unnamed_addr #8 align 2 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !14
+// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
+// CHECK:STDOUT:   call void @_Cfunc__carbon_thunk.Derived.Main(ptr noundef nonnull align 8 dereferenceable(12) %this1)
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: inlinehint mustprogress nounwind uwtable
 // CHECK:STDOUT: define linkonce_odr dso_local void @_ZN11FurtherBaseC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %this) unnamed_addr #3 comdat align 2 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %this.addr = alloca ptr, align 8
-// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !20
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !49
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
 // CHECK:STDOUT:   store ptr getelementptr inbounds inrange(-16, 8) ({ [3 x ptr] }, ptr @_ZTV11FurtherBase, i32 0, i32 0, i32 2), ptr %this1, align 8, !tbaa !16
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder ptr getelementptr inbounds (ptr, ptr @_ZTVN10__cxxabiv120__si_class_type_infoE, i64 2), { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @_ZN6Carbon7DerivedC2Ev, { 1, 0 }
-// CHECK:STDOUT: uselistorder ptr @_ZN6Carbon7DerivedD2Ev, { 2, 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @_ZN6Carbon7DerivedD2Ev, { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @_ZN11FurtherBase17further_base_funcEv, { 2, 1, 0 }
-// CHECK:STDOUT: uselistorder ptr @_ZN4Base4funcEv, { 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @llvm.load.relative.i32, { 1, 0 }
 // CHECK:STDOUT:
-// CHECK:STDOUT: attributes #0 = { mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #0 = { mustprogress noinline nounwind optnone uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
 // CHECK:STDOUT: attributes #1 = { mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
 // CHECK:STDOUT: attributes #2 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
 // CHECK:STDOUT: attributes #3 = { inlinehint mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
-// CHECK:STDOUT: attributes #4 = { nounwind }
-// CHECK:STDOUT: attributes #5 = { alwaysinline nounwind }
+// CHECK:STDOUT: attributes #4 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #5 = { nounwind }
+// CHECK:STDOUT: attributes #6 = { alwaysinline nounwind }
+// CHECK:STDOUT: attributes #7 = { nocallback nofree nosync nounwind willreturn memory(argmem: read) }
+// CHECK:STDOUT: attributes #8 = { alwaysinline mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
 // CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1, !2, !3, !4}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!5}
@@ -302,33 +270,40 @@ auto DoThing() -> int {
 // CHECK:STDOUT: !11 = !{!12, !12, i64 0}
 // CHECK:STDOUT: !12 = !{!"p1 _ZTS4Base", !13, i64 0}
 // CHECK:STDOUT: !13 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !14 = !{}
-// CHECK:STDOUT: !15 = !{i64 8}
+// CHECK:STDOUT: !14 = !{!15, !15, i64 0}
+// CHECK:STDOUT: !15 = !{!"p1 _ZTSN6Carbon7DerivedE", !13, i64 0}
 // CHECK:STDOUT: !16 = !{!17, !17, i64 0}
 // CHECK:STDOUT: !17 = !{!"vtable pointer", !10, i64 0}
-// CHECK:STDOUT: !18 = !{!19, !19, i64 0}
-// CHECK:STDOUT: !19 = !{!"p1 _ZTSN6Carbon7DerivedE", !13, i64 0}
-// CHECK:STDOUT: !20 = !{!21, !21, i64 0}
-// CHECK:STDOUT: !21 = !{!"p1 _ZTS11FurtherBase", !13, i64 0}
-// CHECK:STDOUT: !22 = distinct !DISubprogram(name: "other_func", linkageName: "_Cother_func.Derived.Main", scope: null, file: !6, line: 32, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !27)
-// CHECK:STDOUT: !23 = !DISubroutineType(types: !24)
-// CHECK:STDOUT: !24 = !{!25, !26}
-// CHECK:STDOUT: !25 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
-// CHECK:STDOUT: !26 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
-// CHECK:STDOUT: !27 = !{!28}
-// CHECK:STDOUT: !28 = !DILocalVariable(arg: 1, scope: !22, type: !26)
-// CHECK:STDOUT: !29 = !DILocation(line: 33, column: 5, scope: !22)
-// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "__destroy_thunk", linkageName: "_C__destroy_thunk:thunk.Derived.Main", scope: null, file: !6, line: 27, type: !31, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !33)
-// CHECK:STDOUT: !31 = !DISubroutineType(types: !32)
-// CHECK:STDOUT: !32 = !{null, !26}
-// CHECK:STDOUT: !33 = !{!34}
-// CHECK:STDOUT: !34 = !DILocalVariable(arg: 1, scope: !30, type: !26)
-// CHECK:STDOUT: !35 = !DILocation(line: 27, column: 1, scope: !30)
-// CHECK:STDOUT: !36 = distinct !DISubprogram(name: "Op", linkageName: "_COp.bfe31446004e2b71:core.Destroy.Core", scope: null, file: !6, line: 27, type: !31, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !37)
-// CHECK:STDOUT: !37 = !{!38}
-// CHECK:STDOUT: !38 = !DILocalVariable(arg: 1, scope: !36, type: !26)
-// CHECK:STDOUT: !39 = !DILocation(line: 27, column: 1, scope: !36)
-// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "Op", linkageName: "_COp.12e0d0434542305a:core.Destroy.Core", scope: null, file: !6, line: 27, type: !31, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
-// CHECK:STDOUT: !41 = !{!42}
-// CHECK:STDOUT: !42 = !DILocalVariable(arg: 1, scope: !40, type: !26)
-// CHECK:STDOUT: !43 = !DILocation(line: 27, column: 1, scope: !40)
+// CHECK:STDOUT: !18 = distinct !DISubprogram(name: "other_func", linkageName: "_Cother_func.Derived.Main", scope: null, file: !6, line: 26, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !22)
+// CHECK:STDOUT: !19 = !DISubroutineType(types: !20)
+// CHECK:STDOUT: !20 = !{null, !21}
+// CHECK:STDOUT: !21 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
+// CHECK:STDOUT: !22 = !{!23}
+// CHECK:STDOUT: !23 = !DILocalVariable(arg: 1, scope: !18, type: !21)
+// CHECK:STDOUT: !24 = !DILocation(line: 26, column: 3, scope: !18)
+// CHECK:STDOUT: !25 = distinct !DISubprogram(name: "func", linkageName: "_Cfunc.Derived.Main", scope: null, file: !6, line: 28, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !26)
+// CHECK:STDOUT: !26 = !{!27}
+// CHECK:STDOUT: !27 = !DILocalVariable(arg: 1, scope: !25, type: !21)
+// CHECK:STDOUT: !28 = !DILocation(line: 28, column: 3, scope: !25)
+// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "__destroy_thunk", linkageName: "_C__destroy_thunk:thunk.Derived.Main", scope: null, file: !6, line: 22, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
+// CHECK:STDOUT: !30 = !{!31}
+// CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !29, type: !21)
+// CHECK:STDOUT: !32 = !DILocation(line: 22, column: 1, scope: !29)
+// CHECK:STDOUT: !33 = distinct !DISubprogram(name: "Op", linkageName: "_COp.bfe31446004e2b71:core.Destroy.Core", scope: null, file: !6, line: 22, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !34)
+// CHECK:STDOUT: !34 = !{!35}
+// CHECK:STDOUT: !35 = !DILocalVariable(arg: 1, scope: !33, type: !21)
+// CHECK:STDOUT: !36 = !DILocation(line: 22, column: 1, scope: !33)
+// CHECK:STDOUT: !37 = distinct !DISubprogram(name: "Op", linkageName: "_COp.12e0d0434542305a:core.Destroy.Core", scope: null, file: !6, line: 22, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !38)
+// CHECK:STDOUT: !38 = !{!39}
+// CHECK:STDOUT: !39 = !DILocalVariable(arg: 1, scope: !37, type: !21)
+// CHECK:STDOUT: !40 = !DILocation(line: 22, column: 1, scope: !37)
+// CHECK:STDOUT: !41 = distinct !DISubprogram(name: "func__carbon_thunk", linkageName: "_Cfunc__carbon_thunk.Derived.Main", scope: null, file: !6, line: 28, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !42)
+// CHECK:STDOUT: !42 = !{!43}
+// CHECK:STDOUT: !43 = !DILocalVariable(arg: 1, scope: !41, type: !21)
+// CHECK:STDOUT: !44 = !DILocation(line: 28, column: 3, scope: !41)
+// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "other_func__carbon_thunk", linkageName: "_Cother_func__carbon_thunk.Derived.Main", scope: null, file: !6, line: 26, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !46)
+// CHECK:STDOUT: !46 = !{!47}
+// CHECK:STDOUT: !47 = !DILocalVariable(arg: 1, scope: !45, type: !21)
+// CHECK:STDOUT: !48 = !DILocation(line: 26, column: 3, scope: !45)
+// CHECK:STDOUT: !49 = !{!50, !50, i64 0}
+// CHECK:STDOUT: !50 = !{!"p1 _ZTS11FurtherBase", !13, i64 0}
diff --git a/toolchain/lower/testdata/interop/cpp/class/virtual_fn.carbon b/toolchain/lower/testdata/interop/cpp/class/virtual_fn.carbon
index 34d400277f03..45e51c92607a 100644
--- a/toolchain/lower/testdata/interop/cpp/class/virtual_fn.carbon
+++ b/toolchain/lower/testdata/interop/cpp/class/virtual_fn.carbon
@@ -95,7 +95,7 @@ void delete_new_Base() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %p = alloca ptr, align 8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %p) #8
-// CHECK:STDOUT:   %call = call noalias noundef nonnull ptr @_Znwm(i64 noundef 8) #10
+// CHECK:STDOUT:   %call = call noalias noundef nonnull ptr @_Znwm(i64 noundef 8) #11
 // CHECK:STDOUT:   call void @_ZN6Carbon5FinalC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %call) #8
 // CHECK:STDOUT:   store ptr %call, ptr %p, align 8, !tbaa !11
 // CHECK:STDOUT:   %0 = load ptr, ptr %p, align 8, !tbaa !11
@@ -104,7 +104,7 @@ void delete_new_Base() {
 // CHECK:STDOUT:
 // CHECK:STDOUT: delete.notnull:                                   ; preds = %entry
 // CHECK:STDOUT:   call void @_ZN6Carbon5FinalD2Ev(ptr noundef nonnull align 8 dead_on_return(8) dereferenceable(8) %0) #8
-// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %0, i64 noundef 8) #11
+// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %0, i64 noundef 8) #12
 // CHECK:STDOUT:   br label %delete.end
 // CHECK:STDOUT:
 // CHECK:STDOUT: delete.end:                                       ; preds = %delete.notnull, %entry
@@ -151,7 +151,7 @@ void delete_new_Base() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %p = alloca ptr, align 8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %p) #8
-// CHECK:STDOUT:   %call = call noalias noundef nonnull ptr @_Znwm(i64 noundef 8) #10
+// CHECK:STDOUT:   %call = call noalias noundef nonnull ptr @_Znwm(i64 noundef 8) #11
 // CHECK:STDOUT:   call void @_ZN6Carbon4BaseC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %call) #8
 // CHECK:STDOUT:   store ptr %call, ptr %p, align 8, !tbaa !16
 // CHECK:STDOUT:   %0 = load ptr, ptr %p, align 8, !tbaa !16
@@ -220,19 +220,40 @@ void delete_new_Base() {
 // CHECK:STDOUT:   ret void, !dbg !36
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_C__destroy_thunk:thunk.Base.Main"(ptr %self) #6 !dbg !37 {
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CF__carbon_thunk.Final.Main(ptr %self) #8 !dbg !37 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   call void @"_COp.96a711151205ee34:core.Destroy.Core"(ptr %self), !dbg !40
+// CHECK:STDOUT:   %Final.F.call.vtable = load ptr, ptr %self, align 8, !dbg !40
+// CHECK:STDOUT:   %Final.F.call = call ptr @llvm.load.relative.i32(ptr %Final.F.call.vtable, i32 8), !dbg !40
+// CHECK:STDOUT:   call void %Final.F.call(ptr %self), !dbg !40
 // CHECK:STDOUT:   ret void, !dbg !40
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.96a711151205ee34:core.Destroy.Core"(ptr %self) #8 !dbg !41 {
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_C__destroy_thunk:thunk.Base.Main"(ptr %self) #6 !dbg !41 {
 // CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @"_COp.96a711151205ee34:core.Destroy.Core"(ptr %self), !dbg !44
 // CHECK:STDOUT:   ret void, !dbg !44
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define weak_odr void @"_COp.96a711151205ee34:core.Destroy.Core"(ptr %self) #8 !dbg !45 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   ret void, !dbg !48
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CF__carbon_thunk.Base.Main(ptr %self) #8 !dbg !49 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %Base.F.call.vtable = load ptr, ptr %self, align 8, !dbg !52
+// CHECK:STDOUT:   %Base.F.call = call ptr @llvm.load.relative.i32(ptr %Base.F.call.vtable, i32 8), !dbg !52
+// CHECK:STDOUT:   call void %Base.F.call(ptr %self), !dbg !52
+// CHECK:STDOUT:   ret void, !dbg !52
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: read)
+// CHECK:STDOUT: declare ptr @llvm.load.relative.i32(ptr, i32) #9
+// CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: inlinehint mustprogress nounwind uwtable
 // CHECK:STDOUT: define linkonce_odr dso_local void @_ZN1AC2Ev(ptr noundef nonnull align 8 dereferenceable(8) %this) unnamed_addr #3 comdat align 2 {
 // CHECK:STDOUT: entry:
@@ -250,11 +271,11 @@ void delete_new_Base() {
 // CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !11
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
 // CHECK:STDOUT:   call void @_ZN6Carbon5FinalD2Ev(ptr noundef nonnull align 8 dead_on_return(8) dereferenceable(8) %this1) #8
-// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %this1, i64 noundef 8) #11
+// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %this1, i64 noundef 8) #12
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: declare void @_ZNK1A1FEv(ptr noundef nonnull align 8 dereferenceable(8)) unnamed_addr #9
+// CHECK:STDOUT: declare void @_ZNK1A1FEv(ptr noundef nonnull align 8 dereferenceable(8)) unnamed_addr #10
 // CHECK:STDOUT:
 // CHECK:STDOUT: declare void @__cxa_pure_virtual() unnamed_addr
 // CHECK:STDOUT:
@@ -280,12 +301,13 @@ void delete_new_Base() {
 // CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !16
 // CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
 // CHECK:STDOUT:   call void @_ZN6Carbon4BaseD2Ev(ptr noundef nonnull align 8 dead_on_return(8) dereferenceable(8) %this1) #8
-// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %this1, i64 noundef 8) #11
+// CHECK:STDOUT:   call void @_ZdlPvm(ptr noundef %this1, i64 noundef 8) #12
 // CHECK:STDOUT:   ret void
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
 // CHECK:STDOUT: uselistorder ptr @_ZN6Carbon5FinalD2Ev, { 2, 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @llvm.load.relative.i32, { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @_ZN1AC2Ev, { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @_ZNK1A1FEv, { 2, 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @__cxa_pure_virtual, { 1, 0 }
@@ -300,9 +322,10 @@ void delete_new_Base() {
 // CHECK:STDOUT: attributes #6 = { alwaysinline nounwind }
 // CHECK:STDOUT: attributes #7 = { nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
 // CHECK:STDOUT: attributes #8 = { nounwind }
-// CHECK:STDOUT: attributes #9 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
-// CHECK:STDOUT: attributes #10 = { builtin allocsize(0) }
-// CHECK:STDOUT: attributes #11 = { builtin nounwind }
+// CHECK:STDOUT: attributes #9 = { nocallback nofree nosync nounwind willreturn memory(argmem: read) }
+// CHECK:STDOUT: attributes #10 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #11 = { builtin allocsize(0) }
+// CHECK:STDOUT: attributes #12 = { builtin nounwind }
 // CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1, !2, !3, !4}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!5}
@@ -345,11 +368,19 @@ void delete_new_Base() {
 // CHECK:STDOUT: !34 = !{!35}
 // CHECK:STDOUT: !35 = !DILocalVariable(arg: 1, scope: !33, type: !25)
 // CHECK:STDOUT: !36 = !DILocation(line: 12, column: 1, scope: !33)
-// CHECK:STDOUT: !37 = distinct !DISubprogram(name: "__destroy_thunk", linkageName: "_C__destroy_thunk:thunk.Base.Main", scope: null, file: !6, line: 17, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !38)
+// CHECK:STDOUT: !37 = distinct !DISubprogram(name: "F__carbon_thunk", linkageName: "_CF__carbon_thunk.Final.Main", scope: null, file: !6, line: 14, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !38)
 // CHECK:STDOUT: !38 = !{!39}
 // CHECK:STDOUT: !39 = !DILocalVariable(arg: 1, scope: !37, type: !25)
-// CHECK:STDOUT: !40 = !DILocation(line: 17, column: 1, scope: !37)
-// CHECK:STDOUT: !41 = distinct !DISubprogram(name: "Op", linkageName: "_COp.96a711151205ee34:core.Destroy.Core", scope: null, file: !6, line: 17, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !42)
+// CHECK:STDOUT: !40 = !DILocation(line: 14, column: 3, scope: !37)
+// CHECK:STDOUT: !41 = distinct !DISubprogram(name: "__destroy_thunk", linkageName: "_C__destroy_thunk:thunk.Base.Main", scope: null, file: !6, line: 17, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !42)
 // CHECK:STDOUT: !42 = !{!43}
 // CHECK:STDOUT: !43 = !DILocalVariable(arg: 1, scope: !41, type: !25)
 // CHECK:STDOUT: !44 = !DILocation(line: 17, column: 1, scope: !41)
+// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "Op", linkageName: "_COp.96a711151205ee34:core.Destroy.Core", scope: null, file: !6, line: 17, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !46)
+// CHECK:STDOUT: !46 = !{!47}
+// CHECK:STDOUT: !47 = !DILocalVariable(arg: 1, scope: !45, type: !25)
+// CHECK:STDOUT: !48 = !DILocation(line: 17, column: 1, scope: !45)
+// CHECK:STDOUT: !49 = distinct !DISubprogram(name: "F__carbon_thunk", linkageName: "_CF__carbon_thunk.Base.Main", scope: null, file: !6, line: 19, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !50)
+// CHECK:STDOUT: !50 = !{!51}
+// CHECK:STDOUT: !51 = !DILocalVariable(arg: 1, scope: !49, type: !25)
+// CHECK:STDOUT: !52 = !DILocation(line: 19, column: 3, scope: !49)