llvm-project/clang/test/CodeGenCXX/microsoft-abi-extern-template.cpp
Mariya Podchishchaeva d6942d54f6
[MS][clang] Add support for vector deleting destructors (#126240)
Whereas it is UB in terms of the standard to delete an array of objects
via pointer whose static type doesn't match its dynamic type, MSVC
supports an extension allowing to do it.
Aside from array deletion not working correctly in the mentioned case,
currently not having this extension implemented causes clang to generate
code that is not compatible with the code generated by MSVC, because
clang always puts scalar deleting destructor to the vftable. This PR
aims to resolve these problems.

Fixes https://github.com/llvm/llvm-project/issues/19772
2025-03-04 09:17:50 +01:00

26 lines
1.1 KiB
C++

// RUN: %clang_cc1 -fno-rtti-data -O1 -disable-llvm-passes %s -emit-llvm -o - -triple x86_64-windows-msvc | FileCheck %s
// Even though Foo<int> has an extern template declaration, we have to emit our
// own copy the vftable when emitting the available externally constructor.
// CHECK: @"??_7?$Foo@H@@6B@" = linkonce_odr unnamed_addr constant { [1 x ptr] } { [1 x ptr] [
// CHECK-SAME: ptr @"??_E?$Foo@H@@UEAAPEAXI@Z"
// CHECK-SAME: ] }, comdat
// CHECK-LABEL: define dso_local noundef ptr @"?f@@YAPEAU?$Foo@H@@XZ"()
// CHECK: call noundef ptr @"??0?$Foo@H@@QEAA@XZ"(ptr {{[^,]*}} %{{.*}})
// CHECK: define available_externally dso_local noundef ptr @"??0?$Foo@H@@QEAA@XZ"(ptr {{[^,]*}} returned align 8 dereferenceable(8) %this)
// CHECK: store {{.*}} @"??_7?$Foo@H@@6B@"
// CHECK: define linkonce_odr dso_local noundef ptr @"??_G?$Foo@H@@UEAAPEAXI@Z"(ptr {{[^,]*}} %this, i32 noundef %should_call_delete)
struct Base {
virtual ~Base();
};
template <typename T> struct Foo : Base {
Foo() {}
};
extern template class Foo<int>;
Foo<int> *f() { return new Foo<int>(); }