Skip to content

[Clang] Fix FE crash during CGCoroutine GRO Alloca Emission #148962

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jul 15, 2025
Merged

[Clang] Fix FE crash during CGCoroutine GRO Alloca Emission #148962

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 9 additions & 5 deletions clang/lib/CodeGen/CGCoroutine.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -707,11 +707,15 @@ struct GetReturnObjectManager {
Builder.CreateStore(Builder.getFalse(), GroActiveFlag);

GroEmission = CGF.EmitAutoVarAlloca(*GroVarDecl);
auto *GroAlloca = dyn_cast_or_null<llvm::AllocaInst>(
GroEmission.getOriginalAllocatedAddress().getPointer());
assert(GroAlloca && "expected alloca to be emitted");
GroAlloca->setMetadata(llvm::LLVMContext::MD_coro_outside_frame,
llvm::MDNode::get(CGF.CGM.getLLVMContext(), {}));

if (!GroVarDecl->isNRVOVariable()) {
// NRVO variables don't have allocas and won't have the same issue.
auto *GroAlloca = dyn_cast_or_null<llvm::AllocaInst>(
GroEmission.getOriginalAllocatedAddress().getPointer());
assert(GroAlloca && "expected alloca to be emitted");
GroAlloca->setMetadata(llvm::LLVMContext::MD_coro_outside_frame,
llvm::MDNode::get(CGF.CGM.getLLVMContext(), {}));
}

// Remember the top of EHStack before emitting the cleanup.
auto old_top = CGF.EHStack.stable_begin();
Expand Down
29 changes: 28 additions & 1 deletion clang/test/CodeGenCoroutines/coro-gro.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -106,4 +106,31 @@ invoker g() {
// CHECK: call void @_ZN7invoker15invoker_promise17get_return_objectEv({{.*}} %[[AggRes]]
co_return;
}
// CHECK: ![[OutFrameMetadata]] = !{}

namespace gh148953 {

struct Task {
struct promise_type {
Task get_return_object();
std::suspend_always initial_suspend() { return {}; }
std::suspend_always final_suspend() noexcept { return {}; }
void return_void() {}
void unhandled_exception() {}
};
Task() {}
// Different from `invoker`, this Task is copy constructible.
Task(const Task&) {};
};

// NRVO on const qualified return type should work.
// CHECK: define{{.*}} void @_ZN8gh1489537exampleEv({{.*}} sret(%"struct.gh148953::Task") align 1 %[[NrvoRes:.+]])
const Task example() {
// CHECK: %[[ResultPtr:.+]] = alloca ptr
// CHECK: store ptr %[[NrvoRes]], ptr %[[ResultPtr]]
// CHECK: coro.init:
// CHECK: call void @_ZN8gh1489534Task12promise_type17get_return_objectEv({{.*}} %[[NrvoRes:.+]], {{.*}})
co_return;
}

} // namespace gh148953
// CHECK: ![[OutFrameMetadata]] = !{}
Loading