| Message ID | Zc_cVI5s-EGwO65d@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] c++: wrong looser excep spec for dep noexcept [PR113158] | expand |
On 2/16/24 17:06, Marek Polacek wrote: > On Fri, Feb 16, 2024 at 04:39:47PM -0500, Patrick Palka wrote: >> On Fri, 16 Feb 2024, Marek Polacek wrote: >>> + /* We also have to defer checking when we're in a template and couldn't >>> + instantiate & evaluate the noexcept to true/false. */ >>> + if (processing_template_decl) >>> + if ((base_throw >>> + && (base_throw != noexcept_true_spec >>> + || base_throw != noexcept_false_spec)) >> >> Shouldn't these innermost || be &&? > > D'oh, yes, what a dumb mistake. But that shows that we could also just > always return true in a template ;). > > Fixed. dg.exp passed so far. OK. > -- >8 -- > Here we find ourselves in maybe_check_overriding_exception_spec in > a template context where we can't instantiate a dependent noexcept. > That's OK, but we have to defer the checking otherwise we give wrong > errors. > > PR c++/113158 > > gcc/cp/ChangeLog: > > * search.cc (maybe_check_overriding_exception_spec): Defer checking > when a noexcept couldn't be instantiated & evaluated to false/true. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp0x/noexcept83.C: New test. > --- > gcc/cp/search.cc | 11 ++++++++ > gcc/testsuite/g++.dg/cpp0x/noexcept83.C | 37 +++++++++++++++++++++++++ > 2 files changed, 48 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/cpp0x/noexcept83.C > > diff --git a/gcc/cp/search.cc b/gcc/cp/search.cc > index c948839dc53..827f48e8604 100644 > --- a/gcc/cp/search.cc > +++ b/gcc/cp/search.cc > @@ -1975,6 +1975,17 @@ maybe_check_overriding_exception_spec (tree overrider, tree basefn) > || UNPARSED_NOEXCEPT_SPEC_P (over_throw)) > return true; > > + /* We also have to defer checking when we're in a template and couldn't > + instantiate & evaluate the noexcept to true/false. */ > + if (processing_template_decl) > + if ((base_throw > + && base_throw != noexcept_true_spec > + && base_throw != noexcept_false_spec) > + || (over_throw > + && over_throw != noexcept_true_spec > + && over_throw != noexcept_false_spec)) > + return true; > + > if (!comp_except_specs (base_throw, over_throw, ce_derived)) > { > auto_diagnostic_group d; > diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept83.C b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C > new file mode 100644 > index 00000000000..47832bbb44d > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C > @@ -0,0 +1,37 @@ > +// PR c++/113158 > +// { dg-do compile { target c++11 } } > + > +template<typename T> > +struct V { > + static constexpr bool t = false; > +}; > +struct base { > + virtual int f() = 0; > +}; > + > +template<typename T> > +struct derived : base { > + int f() noexcept(V<T>::t) override; > +}; > + > +struct base2 { > + virtual int f() noexcept = 0; > +}; > + > +template<bool B> > +struct W { > + static constexpr bool t = B; > +}; > + > +template<bool B> > +struct derived2 : base2 { > + int f() noexcept(W<B>::t) override; // { dg-error "looser exception specification" } > +}; > + > +void > +g () > +{ > + derived<int> d1; > + derived2<false> d2; // { dg-message "required from here" } > + derived2<true> d3; > +} > > base-commit: cd503b0616462445381a8232fb753239d319af76
diff --git a/gcc/cp/search.cc b/gcc/cp/search.cc index c948839dc53..827f48e8604 100644 --- a/gcc/cp/search.cc +++ b/gcc/cp/search.cc @@ -1975,6 +1975,17 @@ maybe_check_overriding_exception_spec (tree overrider, tree basefn) || UNPARSED_NOEXCEPT_SPEC_P (over_throw)) return true; + /* We also have to defer checking when we're in a template and couldn't + instantiate & evaluate the noexcept to true/false. */ + if (processing_template_decl) + if ((base_throw + && base_throw != noexcept_true_spec + && base_throw != noexcept_false_spec) + || (over_throw + && over_throw != noexcept_true_spec + && over_throw != noexcept_false_spec)) + return true; + if (!comp_except_specs (base_throw, over_throw, ce_derived)) { auto_diagnostic_group d; diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept83.C b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C new file mode 100644 index 00000000000..47832bbb44d --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/noexcept83.C @@ -0,0 +1,37 @@ +// PR c++/113158 +// { dg-do compile { target c++11 } } + +template<typename T> +struct V { + static constexpr bool t = false; +}; +struct base { + virtual int f() = 0; +}; + +template<typename T> +struct derived : base { + int f() noexcept(V<T>::t) override; +}; + +struct base2 { + virtual int f() noexcept = 0; +}; + +template<bool B> +struct W { + static constexpr bool t = B; +}; + +template<bool B> +struct derived2 : base2 { + int f() noexcept(W<B>::t) override; // { dg-error "looser exception specification" } +}; + +void +g () +{ + derived<int> d1; + derived2<false> d2; // { dg-message "required from here" } + derived2<true> d3; +}