| Message ID | cb175885-cdeb-b6c9-0306-8f891183e21f@acm.org |
|---|---|
| State | New |
| Headers | show |
On Wed, Feb 8, 2017 at 10:08 PM, Nathan Sidwell <nathan@acm.org> wrote: > > 'potentially constructed subobject' appears to be a term without definition. [special]/5: For a class, its non-static data members, its non-virtual direct base classes, and, if the class is not abstract, its virtual base classes are called its potentially constructed subobjects.
On 02/08/2017 09:33 AM, Tim Song wrote: > On Wed, Feb 8, 2017 at 10:08 PM, Nathan Sidwell <nathan@acm.org> wrote: >> >> 'potentially constructed subobject' appears to be a term without definition. > > [special]/5: > > For a class, its non-static data members, its non-virtual direct base > classes, and, if the class is not abstract, its virtual base classes > are called its potentially constructed subobjects. thanks. That suggests that this, pedantically, is not a defect. It's certainly an unwelcome surprise though. nathan
On Wed, Feb 8, 2017 at 10:09 AM, Nathan Sidwell <nathan@acm.org> wrote: > On 02/08/2017 09:33 AM, Tim Song wrote: >> On Wed, Feb 8, 2017 at 10:08 PM, Nathan Sidwell <nathan@acm.org> wrote: >>> 'potentially constructed subobject' appears to be a term without >>> definition. >> >> [special]/5: >> >> For a class, its non-static data members, its non-virtual direct base >> classes, and, if the class is not abstract, its virtual base classes >> are called its potentially constructed subobjects. > > thanks. That suggests that this, pedantically, is not a defect. It's > certainly an unwelcome surprise though. Perhaps the defect is in the standard. Will you email core about it? Jason
On 02/08/2017 12:53 PM, Jason Merrill wrote:
> Perhaps the defect is in the standard. Will you email core about it?
Correct, done.
nathan
2017-02-08 Nathan Sidwell <nathan@acm.org> PR c++/79393 * method.c (synthesized_method_walk): Check vbases of abstract classes for eh spec. Index: cp/method.c =================================================================== --- cp/method.c (revision 245277) +++ cp/method.c (working copy) @@ -1660,12 +1660,21 @@ synthesized_method_walk (tree ctype, spe /* Already examined vbases above. */; else if (vec_safe_is_empty (vbases)) /* No virtual bases to worry about. */; - else if (ABSTRACT_CLASS_TYPE_P (ctype) && cxx_dialect >= cxx14) + else if (ABSTRACT_CLASS_TYPE_P (ctype) && cxx_dialect >= cxx14 + && !(sfk == sfk_destructor && spec_p)) /* Vbase cdtors are not relevant. */; else { if (constexpr_p) *constexpr_p = false; + + /* We might not be concerned with access, just the eh-spec for each + potentially-constructed sub-object. */ + bool no_access_check = (cxx_dialect >= cxx14 + && ABSTRACT_CLASS_TYPE_P (ctype)); + + if (no_access_check) + push_deferring_access_checks (dk_no_check); FOR_EACH_VEC_ELT (*vbases, i, base_binfo) synthesized_method_base_walk (binfo, base_binfo, quals, copy_arg_p, move_p, ctor_p, @@ -1673,6 +1682,8 @@ synthesized_method_walk (tree ctype, spe fnname, flags, diag, spec_p, trivial_p, deleted_p, constexpr_p); + if (no_access_check) + pop_deferring_access_checks (); } /* Now handle the non-static data members. */ Index: testsuite/g++.dg/cpp1y/pr79393.C =================================================================== --- testsuite/g++.dg/cpp1y/pr79393.C (revision 0) +++ testsuite/g++.dg/cpp1y/pr79393.C (working copy) @@ -0,0 +1,21 @@ +// { dg-do compile { target c++14 } } +// PR c++/79393 deduced eh spec, deleted dtors and vbases + +struct A3; + +struct VDT { + virtual ~VDT () noexcept (false); +}; + +struct A1 : virtual VDT { + virtual void abstract () = 0; +}; + +struct A2 : A1 { }; + +struct A3 : A2 +{ + virtual void abstract (); +}; + +A3 a3;