https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108620
Bug ID: 108620
Summary: internal compiler error: in instantiate_type, at
cp/class.cc:8742 when assign the return value of
co_yield to a member of class/struct
Product: gcc
Version: 12.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: owt5008137 at live dot com
Target Milestone: ---
## GCC Version
```
$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/opt/gcc-12/libexec/gcc/x86_64-pc-linux-gnu/12.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-12.2.0/configure --prefix=/opt/gcc-12
--with-gmp=/opt/gcc-12 --with-mpc=/opt/gcc-12 --with-mpfr=/opt/gcc-12
--with-isl=/opt/gcc-12 --with-zstd=/opt/gcc-12
--with-target-bdw-gc=/opt/gcc-12/multilib/64,32=/opt/gcc-12/multilib/32
--enable-shared --enable-static --enable-gnu-unique-object --enable-bootstrap
--enable-build-with-cxx --disable-libjava-multilib --enable-checking=release
--enable-gold --enable-ld --enable-libada --enable-lto --enable-objc-gc
--enable-vtable-verify --enable-linker-build-id --enable-rpath
--enable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.2.0 (GCC)
```
## Command and output
```
$ g++ test.cpp -std=c++20 -freport-bug
test.cpp: In instantiation of ‘task<std::__cxx11::basic_string<char> >
call2(TArg&&, container&) [with TArg = std::__cxx11::basic_string<char>]’:
test.cpp:91:21: required from here
test.cpp:79:16: internal compiler error: in instantiate_type, at
cp/class.cc:8742
79 | output.ptr = co_yield task<TArg>::yield_private_data();
| ~~~~~~~~~~~^~~~~~~~~~
0x68984f instantiate_type(tree_node*, tree_node*, int)
../../gcc-12.2.0/gcc/cp/class.cc:8742
0x8a6a6c convert_for_assignment
../../gcc-12.2.0/gcc/cp/typeck.cc:9863
0x8a8ce3 cp_build_modify_expr(unsigned int, tree_node*, tree_code, tree_node*,
int)
../../gcc-12.2.0/gcc/cp/typeck.cc:9277
0x8a95bb build_x_modify_expr(unsigned int, tree_node*, tree_code, tree_node*,
tree_node*, int)
../../gcc-12.2.0/gcc/cp/typeck.cc:9373
0x83b8aa tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc-12.2.0/gcc/cp/pt.cc:20588
0x84b468 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:19576
0x84c417 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18547
0x84c417 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18589
0x84c9b2 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18547
0x84c9b2 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18561
0x84bfa8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18547
0x84bfa8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:18918
0x84a9cc tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:26532
0x84a9cc instantiate_body
../../gcc-12.2.0/gcc/cp/pt.cc:26532
0x84b289 instantiate_decl(tree_node*, bool, bool)
../../gcc-12.2.0/gcc/cp/pt.cc:26824
0x85fd6b instantiate_pending_templates(int)
../../gcc-12.2.0/gcc/cp/pt.cc:26903
0x76539f c_parse_final_cleanups()
../../gcc-12.2.0/gcc/cp/decl2.cc:5128
Please submit a full bug report, with preprocessed source.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Preprocessed source stored into /tmp/ccblstmc.out file, please attach this to
your bugreport.
```
## Source
```
#include <iostream>
#include <memory>
#include <coroutine>
template<class PrivateDataType>
struct task;
template <class PrivateDataType>
struct task_private_data {
inline task_private_data() noexcept : data_(nullptr) {}
inline task_private_data(PrivateDataType* input) noexcept : data_(input) {}
inline task_private_data(task_private_data&& other) noexcept = default;
inline task_private_data& operator=(task_private_data&&) noexcept = default;
inline task_private_data(const task_private_data&) = delete;
inline task_private_data& operator=(const task_private_data&) = delete;
inline ~task_private_data() {}
inline bool await_ready() const noexcept { return true; }
inline PrivateDataType* await_resume() const noexcept { return data_; }
inline void await_suspend(std::coroutine_handle<>) noexcept {}
PrivateDataType* data_;
};
template<class PrivateDataType>
struct task_context {
PrivateDataType data_;
};
template<class PrivateDataType>
struct task {
using self_type = task<PrivateDataType>;
std::shared_ptr<task_context<PrivateDataType>> context_;
task(const std::shared_ptr<task_context<PrivateDataType>>& input):
context_(input) {}
static auto yield_private_data() noexcept { return
task_private_data<PrivateDataType>{}; }
struct promise_type {
std::shared_ptr<task_context<PrivateDataType>> context_;
template<class Input, class... Rest>
promise_type(Input&& input, Rest&&...) {
context_ = std::make_shared<task_context<PrivateDataType>>();
context_->data_ = std::forward<Input>(input);
}
auto get_return_object() noexcept { return self_type{context_}; }
std::suspend_never initial_suspend() noexcept { return {}; }
std::suspend_never final_suspend() noexcept { return {}; }
void unhandled_exception() { throw; }
template<class ReturnType>
void return_value(ReturnType&&) {}
template <class InputPrivateDataType>
inline task_private_data<InputPrivateDataType> yield_value(
task_private_data<InputPrivateDataType>&& input) noexcept {
input.data_ = &context_->data_;
return task_private_data<InputPrivateDataType>(input.data_);
}
};
};
template<class TArg, class OutputType>
task<std::string> call1(TArg&& arg, OutputType& output) {
OutputType* ptr = co_yield task<TArg>::yield_private_data();
output = *ptr;
co_return 0;
}
struct container {
task_private_data<std::string>* ptr;
};
template<class TArg>
task<std::string> call2(TArg&& arg, container& output) {
output.ptr = co_yield task<TArg>::yield_private_data();
co_return 0;
}
int main() {
// success
std::string output1;
call1(std::string("hello1"), output1);
std::cout<< "output1: "<< output1<< std::endl;
// crash
container output2;
auto task2 = call2(std::string("hello2"), output2);
std::cout<< "output2: "<< output2.ptr->data_<< std::endl;
return 0;
}
```
