Hi,
The FE contains a mechanism for cleaning up return expressions if a
function throws during the execution of cleanups prior to the return.
If the original function has a return value with a non-trivial DTOR
and the body contains a var with a DTOR that might throw, the function
decl is marked "throwing_cleanup".
However, we do not [in the coroutine ramp function, which is
synthesised], use any body var types with DTORs that might throw.
The original body [which will then contain the type with the throwing
DTOR] is transformed into the actor function which only contains void
returns, and is also wrapped in a try-catch block.
So (a) the 'throwing_cleanup' is no longer correct for the ramp and
(b) we do not need to transfer it to the actor which only contains
void returns.
this is an ICE-on-valid,
tested on x86_64-darwin, x86_64-linux-gnu,
OK for master / 10.x ?
thanks
Iain
gcc/cp/ChangeLog:
PR c++/95822
* coroutines.cc (morph_fn_to_coro): Unconditionally remove any
set throwing_cleanup marker.
gcc/testsuite/ChangeLog:
PR c++/95822
* g++.dg/coroutines/pr95822.C: New test.
---
gcc/cp/coroutines.cc | 11 +++++++++
gcc/testsuite/g++.dg/coroutines/pr95822.C | 29 +++++++++++++++++++++++
2 files changed, 40 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/coroutines/pr95822.C
diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc
index abfe8d08192..19d2ca3e23e 100644
--- a/gcc/cp/coroutines.cc
+++ b/gcc/cp/coroutines.cc
@@ -4029,6 +4029,17 @@ morph_fn_to_coro (tree orig, tree *resumer, tree
*destroyer)
TREE_OPERAND (body_start, 0) = push_stmt_list ();
}
+ /* If the original function has a return value with a non-trivial DTOR
+ and the body contains a var with a DTOR that might throw, the decl is
+ marked "throwing_cleanup".
+ We do not [in the ramp, which is synthesised here], use any body var
+ types with DTORs that might throw.
+ The original body is transformed into the actor function which only
+ contains void returns, and is also wrapped in a try-catch block.
+ So (a) the 'throwing_cleanup' is not correct for the ramp and (b) we do
+ not need to transfer it to the actor which only contains void returns. */
+ cp_function_chain->throwing_cleanup = false;
+
/* Create the coro frame type, as far as it can be known at this stage.
1. Types we already know. */
diff --git a/gcc/testsuite/g++.dg/coroutines/pr95822.C
b/gcc/testsuite/g++.dg/coroutines/pr95822.C
new file mode 100644
index 00000000000..f6284aa417e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/coroutines/pr95822.C
@@ -0,0 +1,29 @@
+#include <coroutine>
+
+struct task {
+ struct promise_type {
+ auto initial_suspend() noexcept { return std::suspend_always{}; }
+ auto final_suspend() noexcept { return std::suspend_always{}; }
+ void return_void() {}
+ task get_return_object() { return task{}; }
+ void unhandled_exception() noexcept {}
+ };
+
+ ~task() noexcept {}
+
+ bool await_ready() const noexcept { return false; }
+ void await_suspend(std::coroutine_handle<>) noexcept {}
+ void await_resume() noexcept {}
+};
+
+struct Error {
+ Error() { };
+ ~Error() noexcept(false) {}
+};
+
+task g();
+
+task f() {
+ Error error;
+ co_await g();
+}
--
2.24.1
