On 5/25/24 19:18, Patrick Palka wrote:
Bootstrap and regtest on x86_64-pc-linux-gnu in progress, does this look OK for trunk if successful?
OK.
-- >8 -- When propagating structural equality in build_cp_fntype_variant, we should consider structural equality of the exception-less variant, not of the given type which might use structural equality only because of the (complex) noexcept-spec we're intending to replace, as in maybe_instantiate_noexcept which calls build_exception_variant using the function type with a deferred noexcept-spec. Otherwise we might pessimisticly use structural equality for a function type with a simple instantiated noexcept-spec, leading to a failed LTO-specific sanity check if we later use that (structural-equality) type as the canonical version of some other variant. PR c++/115223 gcc/cp/ChangeLog: * tree.cc (build_cp_fntype_variant): Propagate structural equality of the exception-less variant. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/noexcept87.C: New test. --- gcc/cp/tree.cc | 4 ++++ gcc/testsuite/g++.dg/cpp0x/noexcept87.C | 11 +++++++++++ 2 files changed, 15 insertions(+) create mode 100644 gcc/testsuite/g++.dg/cpp0x/noexcept87.C diff --git a/gcc/cp/tree.cc b/gcc/cp/tree.cc index 4d87661b4ad..f810b8cd777 100644 --- a/gcc/cp/tree.cc +++ b/gcc/cp/tree.cc @@ -2796,6 +2796,10 @@ build_cp_fntype_variant (tree type, cp_ref_qualifier rqual, bool complex_eh_spec_p = (cr && cr != noexcept_true_spec && !UNPARSED_NOEXCEPT_SPEC_P (cr));+ if (!complex_eh_spec_p && TYPE_RAISES_EXCEPTIONS (type))+ /* We want to consider structural equality of the exception-less + variant since we'll be replacing the exception specification. */ + type = build_cp_fntype_variant (type, rqual, /*raises=*/NULL_TREE, late); if (TYPE_STRUCTURAL_EQUALITY_P (type) || complex_eh_spec_p) /* Propagate structural equality. And always use structural equality for function types with a complex noexcept-spec since their identity diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept87.C b/gcc/testsuite/g++.dg/cpp0x/noexcept87.C new file mode 100644 index 00000000000..60b1497472b --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/noexcept87.C @@ -0,0 +1,11 @@ +// PR c++/115223 +// { dg-do compile { target c++11 } } +// { dg-additional-options -flto } + +template<class T> +void f() noexcept(bool(T() || true)); + +void g(int n) { f<int>(); } + +using type = void; +type callDestructorIfNecessary() noexcept {}
