https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117106
--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Marek Polacek <mpola...@gcc.gnu.org>: https://gcc.gnu.org/g:f5ef1f9e8589697086c8cfea6ad07d56050dde96 commit r15-7417-gf5ef1f9e8589697086c8cfea6ad07d56050dde96 Author: Marek Polacek <pola...@redhat.com> Date: Thu Feb 6 08:57:22 2025 -0500 c++: ICE with unparsed noexcept [PR117106] In a member-specification of a class, a noexcept-specifier is a complete-class context. Thus we delay parsing until the end of the class via our DEFERRED_PARSE mechanism; see cp_parser_save_noexcept and cp_parser_late_noexcept_specifier. We also attempt to defer instantiation of noexcept-specifiers in order to reduce the number of instantiations; this is done via DEFERRED_NOEXCEPT. We can even have both, as in noexcept65.C: a DEFERRED_PARSE wrapped in DEFERRED_NOEXCEPT, which uses the DEFPARSE_INSTANTIATIONS mechanism. noexcept65.C works, because when we really need the noexcept, which is when parsing the body of S::A::A(), the noexcept will have been parsed already; noexcepts are parsed before bodies of member function. But in this test we have: struct A { int x; template<class> void foo() noexcept(noexcept(x)) {} auto bar() -> decltype(foo<int>()) {} // #1 }; and I think the decltype in #1 needs the unparsed noexcept before it could have been parsed. clang++ rejects the test and I suppose we should reject it as well, rather than crashing on a DEFERRED_PARSE in tsubst_expr. PR c++/117106 PR c++/118190 gcc/cp/ChangeLog: * pt.cc (maybe_instantiate_noexcept): Give an error if the noexcept hasn't been parsed yet. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/noexcept89.C: New test. * g++.dg/cpp0x/noexcept90.C: New test. Reviewed-by: Jason Merrill <ja...@redhat.com>
