[Bug c++/91706] [8/9/10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[Bug c++/91706] [8/9/10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ppalka at gcc dot gnu.org

--- Comment #5 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Slightly more reduced testcase:


template <bool> struct A;

struct C {
  template <typename> static int c ();
};

template <class T> struct D : C {
  using c = decltype (c<T>);
  using E = A<c::g>;
};

D<int> g;

[Bug c++/91706] [8/9/10/11 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |jason at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

[Bug c++/91706] [8/9/10/11 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|ice-on-invalid-code         |ice-on-valid-code

--- Comment #6 from Jason Merrill <jason at gcc dot gnu.org> ---
Valid variant:

template <bool> struct A;

struct B { static constexpr bool g = false; };

struct C {
  template <typename> static B c ();
};

template <class T> struct D : C {
  using c = decltype (c<T>());
  using E = A<c::g>;
};

D<int> g;

This is a complex interaction of issues.  Looking up c<T> in the definition of
D::c finds C::c, OK.  Looking up c in the definition of E finds D::c, which is
depedent, OK.  Since the alias is not dependent, we strip it from the template
argument, leaving

using E = A<decltype(c<T>())>;

where 'c' still refers to C::c.  But instantiating E looks up 'c' again and
finds D::c, which isn't a function, so things go wrong.

I think the bug here is looking up 'c' in D at instantiation time; the
declaration we found before is not dependent.

[Bug c++/91706] [8/9/10/11 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

--- Comment #7 from Jason Merrill <jason at gcc dot gnu.org> ---
Created attachment 50632
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50632&action=edit
near fix

This seemed like a fix, but it breaks the modules/merge-8 testcase, and
debugging that is being slow.

[Bug c++/91706] [9/10/11/12 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|8.5                         |9.4

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 8 branch is being closed.

[Bug c++/91706] [9/10/11/12 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|9.4                         |9.5

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9.4 is being released, retargeting bugs to GCC 9.5.

[Bug c++/91706] [9/10/11/12 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:f07edb5d7f3e77218ec846a9382f7c1d23e67b71

commit r12-1272-gf07edb5d7f3e77218ec846a9382f7c1d23e67b71
Author: Jason Merrill <jason@redhat.com>
Date:   Fri Apr 16 11:13:40 2021 -0400

    c++: alias with same name as base fn [PR91706]

    This is a bit complex.  Looking up c<T> in the definition of D::c finds
    C::c, OK.  Looking up c in the definition of E finds D::c, OK.  Since the
    alias is not dependent, we strip it from the template argument, leaving

    using E = A<decltype(c<T>())>;

    where 'c' still refers to C::c.  But instantiating E looks up 'c' again and
    finds D::c, which isn't a function, and sadness ensues.

    I think the bug here is looking up 'c' in D at instantiation time; the
    declaration we found before is not dependent.  This seems to happen because
    baselink_for_fns gets BASELINK_BINFO wrong; it is supposed to be the base
    where lookup found the functions, C in this case.

    gcc/cp/ChangeLog:

            PR c++/91706
            * semantics.c (baselink_for_fns): Fix BASELINK_BINFO.

    gcc/testsuite/ChangeLog:

            PR c++/91706
            * g++.dg/template/lookup17.C: New test.

[Bug c++/91706] [9/10/11/12 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:1a98f830332e5a623278aaeea39c2a88177b2a9a

commit r12-1273-g1a98f830332e5a623278aaeea39c2a88177b2a9a
Author: Jason Merrill <jason@redhat.com>
Date:   Fri Apr 16 13:52:02 2021 -0400

    c++: preserve BASELINK from lookup [PR91706]

    In the earlier patch for PR91706 I fixed the BASELINK built by
    baselink_for_fns, but since we already had one from lookup, we should keep
    that one around instead of stripping it.  The removed hunk in
    get_class_binding was a wierdly large amount of code to decide whether to
    pull out BASELINK_FUNCTIONS.

    gcc/cp/ChangeLog:

            PR c++/91706
            * name-lookup.c (get_class_binding): Keep a BASELINK.
            (set_inherited_value_binding_p): Adjust.
            * lambda.c (is_lambda_ignored_entity): Adjust.
            * pt.c (lookup_template_function): Copy a BASELINK before
            modifying it.

[Bug c++/91706] [9/10/11/12 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

--- Comment #12 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jason Merrill
<jason@gcc.gnu.org>:

https://gcc.gnu.org/g:46c1a9f6d03ab444b42c41067597e3fbfba38486

commit r11-8524-g46c1a9f6d03ab444b42c41067597e3fbfba38486
Author: Jason Merrill <jason@redhat.com>
Date:   Fri Apr 16 11:13:40 2021 -0400

    c++: alias with same name as base fn [PR91706]

    This is a bit complex.  Looking up c<T> in the definition of D::c finds
    C::c, OK.  Looking up c in the definition of E finds D::c, OK.  Since the
    alias is not dependent, we strip it from the template argument, leaving

    using E = A<decltype(c<T>())>;

    where 'c' still refers to C::c.  But instantiating E looks up 'c' again and
    finds D::c, which isn't a function, and sadness ensues.

    I think the bug here is looking up 'c' in D at instantiation time; the
    declaration we found before is not dependent.  This seems to happen because
    baselink_for_fns gets BASELINK_BINFO wrong; it is supposed to be the base
    where lookup found the functions, C in this case.

    gcc/cp/ChangeLog:

            PR c++/91706
            * semantics.c (baselink_for_fns): Fix BASELINK_BINFO.

    gcc/testsuite/ChangeLog:

            PR c++/91706
            * g++.dg/template/lookup17.C: New test.

[Bug c++/91706] [9/10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[9/10/11/12 Regression]     |[9/10 Regression] ICE: tree
                   |ICE: tree check: expected   |check: expected class
                   |class 'type', have          |'type', have 'exceptional'
                   |'exceptional' (error_mark)  |(error_mark) in
                   |in                          |equate_type_number_to_die,
                   |equate_type_number_to_die,  |at dwarf2out.c:5782
                   |at dwarf2out.c:5782         |

--- Comment #13 from Jason Merrill <jason at gcc dot gnu.org> ---
Fixed for 11.2/12 so far.  Is there interest in fixing this on the 9/10
branches?

[Bug c++/91706] [9/10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:6816a44dfe1b5fa9414490a18a4aa723b6f38f18

commit r12-1543-g6816a44dfe1b5fa9414490a18a4aa723b6f38f18
Author: Jason Merrill <jason@redhat.com>
Date:   Wed Jun 16 16:09:59 2021 -0400

    c++: static memfn from non-dependent base [PR101078]

    After my patch for PR91706, or before that with the qualified call,
    tsubst_baselink returned a BASELINK with BASELINK_BINFO indicating a base
of
    a still-dependent derived class.  We need to look up the relevant base
binfo
    in the substituted class.

            PR c++/101078
            PR c++/91706

    gcc/cp/ChangeLog:

            * pt.c (tsubst_baselink): Update binfos in non-dependent case.

    gcc/testsuite/ChangeLog:

            * g++.dg/template/access39.C: New test.

[Bug c++/91706] [9/10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706
Bug 91706 depends on bug 101078, which changed state.

Bug 101078 Summary: [9/10 Regression] Rejected code since r12-1272-gf07edb5d7f3e7721
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101078

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

[Bug c++/91706] [10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|9.5                         |10.4

--- Comment #15 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9 branch is being closed

[Bug c++/91706] [10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.4                        |10.5

--- Comment #16 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 10.4 is being released, retargeting bugs to GCC 10.5.

[Bug c++/91706] [10 Regression] ICE: tree check: expected class 'type', have 'exceptional' (error_mark) in equate_type_number_to_die, at dwarf2out.c:5782

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91706

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
      Known to fail|                            |10.5.0, 11.1.0
   Target Milestone|10.5                        |11.2
      Known to work|                            |11.2.0
             Status|ASSIGNED                    |RESOLVED

--- Comment #17 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed in GCC 11.2