1 // RUN: %clang_cc1 -triple=i686 -emit-llvm -o - %s | FileCheck %s
2 
3 
4 struct X;
5 typedef void (X::*memptr)();
6 
7 struct A {
8   virtual memptr f();
9 };
10 
11 struct B {
12   virtual memptr f();
13 };
14 
15 struct C : A, B {
16   C();
17   memptr f() override __attribute__((noinline)) { return nullptr; };
18 };
19 
20 C::C() {}
21 
22 // Make sure the member pointer is returned from the thunk via the return slot.
23 // Because of the tail call, the return value cannot be copied into a local
24 // alloca. (PR39901)
25 
26 // CHECK-LABEL: define linkonce_odr void @_ZThn4_N1C1fEv({ i32, i32 }* noalias sret({ i32, i32 }) align 4 %agg.result, %struct.C* noundef %this)
27 // CHECK: tail call void @_ZN1C1fEv({ i32, i32 }* sret({ i32, i32 }) align 4 %agg.result
28