c++, coroutines: Improve check for throwing final await [PR104051].
Commit Message
We check that the final_suspend () method returns a sane type (i.e. a class
or structure) but, unfortunately, that check has to be later than the one
for a throwing case. If the user returns some nonsensical type from the
method, we need to handle that in the checking for noexcept.
tested on x86_64-darwin, OK for mainline? (when?),
thanks
Iain
Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
PR c++/104051
gcc/cp/ChangeLog:
* coroutines.cc (coro_diagnose_throwing_final_aw_expr): Handle
non-target expression inputs.
gcc/testsuite/ChangeLog:
* g++.dg/coroutines/pr104051.C: New test.
---
gcc/cp/coroutines.cc | 13 +++++-----
gcc/testsuite/g++.dg/coroutines/pr104051.C | 29 ++++++++++++++++++++++
2 files changed, 36 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/coroutines/pr104051.C
Comments
On 4/18/22 11:34, Iain Sandoe wrote:
> We check that the final_suspend () method returns a sane type (i.e. a class
> or structure) but, unfortunately, that check has to be later than the one
> for a throwing case. If the user returns some nonsensical type from the
> method, we need to handle that in the checking for noexcept.
>
> tested on x86_64-darwin, OK for mainline? (when?),
OK.
> thanks
> Iain
>
> Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
>
> PR c++/104051
>
> gcc/cp/ChangeLog:
>
> * coroutines.cc (coro_diagnose_throwing_final_aw_expr): Handle
> non-target expression inputs.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/coroutines/pr104051.C: New test.
> ---
> gcc/cp/coroutines.cc | 13 +++++-----
> gcc/testsuite/g++.dg/coroutines/pr104051.C | 29 ++++++++++++++++++++++
> 2 files changed, 36 insertions(+), 6 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/coroutines/pr104051.C
>
> diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc
> index d2a765cac11..cb9bbed51e6 100644
> --- a/gcc/cp/coroutines.cc
> +++ b/gcc/cp/coroutines.cc
> @@ -883,13 +883,14 @@ coro_diagnose_throwing_fn (tree fndecl)
> static bool
> coro_diagnose_throwing_final_aw_expr (tree expr)
> {
> - tree t = TARGET_EXPR_INITIAL (expr);
> + if (TREE_CODE (expr) == TARGET_EXPR)
> + expr = TARGET_EXPR_INITIAL (expr);
> tree fn = NULL_TREE;
> - if (TREE_CODE (t) == CALL_EXPR)
> - fn = CALL_EXPR_FN(t);
> - else if (TREE_CODE (t) == AGGR_INIT_EXPR)
> - fn = AGGR_INIT_EXPR_FN (t);
> - else if (TREE_CODE (t) == CONSTRUCTOR)
> + if (TREE_CODE (expr) == CALL_EXPR)
> + fn = CALL_EXPR_FN (expr);
> + else if (TREE_CODE (expr) == AGGR_INIT_EXPR)
> + fn = AGGR_INIT_EXPR_FN (expr);
> + else if (TREE_CODE (expr) == CONSTRUCTOR)
> return false;
> else
> {
> diff --git a/gcc/testsuite/g++.dg/coroutines/pr104051.C b/gcc/testsuite/g++.dg/coroutines/pr104051.C
> new file mode 100644
> index 00000000000..ce7ae55405a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/coroutines/pr104051.C
> @@ -0,0 +1,29 @@
> +// { dg-additional-options "-fsyntax-only" }
> +#include <coroutine>
> +#include <vector>
> +template <typename> struct promise {
> + struct final_awaitable {
> + bool await_ready() noexcept;
> + template <typename Promise>
> + std::coroutine_handle<>
> + await_suspend(std::coroutine_handle<Promise>) noexcept;
> + void await_resume() noexcept;
> + };
> + auto get_return_object() {
> + return std::coroutine_handle<promise>::from_promise(*this);
> + }
> + auto initial_suspend() { return std::suspend_always(); }
> + auto final_suspend() noexcept { return true; }
> + void unhandled_exception();
> +};
> +template <typename T> struct task {
> + using promise_type = promise<T>;
> + task(std::coroutine_handle<promise<T>>);
> + bool await_ready();
> + std::coroutine_handle<> await_suspend(std::coroutine_handle<>);
> + T await_resume();
> +};
> +task<std::vector<int>> foo() { // { dg-error {awaitable type 'bool' is not a structure} }
> + while ((co_await foo()).empty())
> + ;
> +}
@@ -883,13 +883,14 @@ coro_diagnose_throwing_fn (tree fndecl)
static bool
coro_diagnose_throwing_final_aw_expr (tree expr)
{
- tree t = TARGET_EXPR_INITIAL (expr);
+ if (TREE_CODE (expr) == TARGET_EXPR)
+ expr = TARGET_EXPR_INITIAL (expr);
tree fn = NULL_TREE;
- if (TREE_CODE (t) == CALL_EXPR)
- fn = CALL_EXPR_FN(t);
- else if (TREE_CODE (t) == AGGR_INIT_EXPR)
- fn = AGGR_INIT_EXPR_FN (t);
- else if (TREE_CODE (t) == CONSTRUCTOR)
+ if (TREE_CODE (expr) == CALL_EXPR)
+ fn = CALL_EXPR_FN (expr);
+ else if (TREE_CODE (expr) == AGGR_INIT_EXPR)
+ fn = AGGR_INIT_EXPR_FN (expr);
+ else if (TREE_CODE (expr) == CONSTRUCTOR)
return false;
else
{
new file mode 100644
@@ -0,0 +1,29 @@
+// { dg-additional-options "-fsyntax-only" }
+#include <coroutine>
+#include <vector>
+template <typename> struct promise {
+ struct final_awaitable {
+ bool await_ready() noexcept;
+ template <typename Promise>
+ std::coroutine_handle<>
+ await_suspend(std::coroutine_handle<Promise>) noexcept;
+ void await_resume() noexcept;
+ };
+ auto get_return_object() {
+ return std::coroutine_handle<promise>::from_promise(*this);
+ }
+ auto initial_suspend() { return std::suspend_always(); }
+ auto final_suspend() noexcept { return true; }
+ void unhandled_exception();
+};
+template <typename T> struct task {
+ using promise_type = promise<T>;
+ task(std::coroutine_handle<promise<T>>);
+ bool await_ready();
+ std::coroutine_handle<> await_suspend(std::coroutine_handle<>);
+ T await_resume();
+};
+task<std::vector<int>> foo() { // { dg-error {awaitable type 'bool' is not a structure} }
+ while ((co_await foo()).empty())
+ ;
+}