Hi Jason, >>It seems that we had not been marking typeid expressions as unevaluated >>so that is also added here.
>This seems to be https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68604 >But only some typeid expressions are unevaluated; the >https://eel.is/c++draft/expr#typeid-4 case (polymorphic glvalue) is not. > .... >In any case let's not mess with it in this patch. Removed, added a note and xfailed the test for it, so that once we get a resolution to PR68604 it should just start XPASSing and we're done. OK for trunk? thanks Iain --- 8< --- >From [expr.await]/2 We should not accept co_await, co_yield in unevaluated contexts. Currently (see PR68604) we do not mark typeid expressions as unevaluated since the standard rules mean that this depends on the value type. gcc/cp/ChangeLog: * coroutines.cc (finish_co_await_expr): Do not allow in an unevaluated context. (finish_co_yield_expr): Likewise. gcc/testsuite/ChangeLog: * g++.dg/coroutines/unevaluated.C: New test. Signed-off-by: Iain Sandoe <i...@sandoe.co.uk> --- gcc/cp/coroutines.cc | 12 +++++++++ gcc/testsuite/g++.dg/coroutines/unevaluated.C | 25 +++++++++++++++++++ 2 files changed, 37 insertions(+) create mode 100644 gcc/testsuite/g++.dg/coroutines/unevaluated.C diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc index a1986282ca7..6b3fe540376 100644 --- a/gcc/cp/coroutines.cc +++ b/gcc/cp/coroutines.cc @@ -1549,6 +1549,12 @@ finish_co_await_expr (location_t kw, tree expr) if (!expr || error_operand_p (expr)) return error_mark_node; + if (cp_unevaluated_operand) + { + error_at (kw, "%qs cannot be used in an unevaluated context","co_await"); + return error_mark_node; + } + if (!coro_common_keyword_context_valid_p (current_function_decl, kw, "co_await")) return error_mark_node; @@ -1629,6 +1635,12 @@ finish_co_yield_expr (location_t kw, tree expr) if (!expr || error_operand_p (expr)) return error_mark_node; + if (cp_unevaluated_operand) + { + error_at (kw, "%qs cannot be used in an unevaluated context","co_yield"); + return error_mark_node; + } + /* Check the general requirements and simple syntax errors. */ if (!coro_common_keyword_context_valid_p (current_function_decl, kw, "co_yield")) diff --git a/gcc/testsuite/g++.dg/coroutines/unevaluated.C b/gcc/testsuite/g++.dg/coroutines/unevaluated.C new file mode 100644 index 00000000000..63dae38dea3 --- /dev/null +++ b/gcc/testsuite/g++.dg/coroutines/unevaluated.C @@ -0,0 +1,25 @@ +// { dg-additional-options "-fsyntax-only" } +#include <typeinfo> +#include <coroutine> + +struct Task { + struct promise_type { + promise_type() = default; + Task get_return_object() { return {}; } + std::suspend_never initial_suspend() { return {}; } + std::suspend_always final_suspend() noexcept { return {}; } + void unhandled_exception() {} + void return_void () {} + std::suspend_never yield_value (int) { return {}; } + }; +}; + +// We do not permit co_await, co_yield outside a function, and so uses in +// noexcept or requirements are covered by that. +Task foo() { + /* This one will currently fail - see PR68604. */ + const std::type_info& ti1 = typeid (co_await std::suspend_never{}); // { dg-error {'co_await' cannot be used in an unevaluated context} "" { xfail *-*-* } } + std::size_t x = sizeof (co_yield (19)); // { dg-error {'co_yield' cannot be used in an unevaluated context} } + decltype (co_await std::suspend_never{}) A; // { dg-error {'co_await' cannot be used in an unevaluated context} } + co_return; +} -- 2.39.2 (Apple Git-143)
