Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for trunk?
-- >8 -- Here we first use and therefore synthesize the local class operator<=> from an unevaluated context, which inadvertently affects synthesization by causing functions used within the definition (such as the copy constructor of std::strong_ordering) to not get marked as odr-used. This patch fixes this by using maybe_push_to_top_level in synthesize_method which ensures that cp_unevaluated_operand is cleared even in the function-local case. PR c++/113063 gcc/cp/ChangeLog: * method.cc (synthesize_method): Use maybe_push_to_top_level and maybe_pop_from_top_level. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/spaceship-synth16.C: New test. --- gcc/cp/method.cc | 12 ++---------- gcc/testsuite/g++.dg/cpp2a/spaceship-synth16.C | 13 +++++++++++++ 2 files changed, 15 insertions(+), 10 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp2a/spaceship-synth16.C diff --git a/gcc/cp/method.cc b/gcc/cp/method.cc index 26e6eb79946..f645066077f 100644 --- a/gcc/cp/method.cc +++ b/gcc/cp/method.cc @@ -1770,8 +1770,6 @@ decl_remember_implicit_trigger_p (tree decl) void synthesize_method (tree fndecl) { - bool nested = (current_function_decl != NULL_TREE); - tree context = decl_function_context (fndecl); bool need_body = true; tree stmt; location_t save_input_location = input_location; @@ -1795,10 +1793,7 @@ synthesize_method (tree fndecl) it now. */ push_deferring_access_checks (dk_no_deferred); - if (! context) - push_to_top_level (); - else if (nested) - push_function_context (); + bool push_to_top = maybe_push_to_top_level (fndecl); input_location = DECL_SOURCE_LOCATION (fndecl); @@ -1843,10 +1838,7 @@ synthesize_method (tree fndecl) input_location = save_input_location; - if (! context) - pop_from_top_level (); - else if (nested) - pop_function_context (); + maybe_pop_from_top_level (push_to_top); pop_deferring_access_checks (); diff --git a/gcc/testsuite/g++.dg/cpp2a/spaceship-synth16.C b/gcc/testsuite/g++.dg/cpp2a/spaceship-synth16.C new file mode 100644 index 00000000000..8e59f7d2e46 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/spaceship-synth16.C @@ -0,0 +1,13 @@ +// PR c++/113063 +// { dg-do link { target c++20 } } + +#include <compare> + +int main() { + struct X { + auto operator<=>(const X&) const = default; + }; + X x; + static_assert(noexcept(x <=> x)); + static_cast<void>(x <=> x); +} -- 2.43.0.76.g1a87c842ec