[Bug c++/100282] New: [11/12 Regression] ICE in dependent_type_p, at cp/pt.c:26813

[Bug c++/100282] New: [11/12 Regression] ICE in dependent_type_p, at cp/pt.c:26813

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

            Bug ID: 100282
           Summary: [11/12 Regression] ICE in dependent_type_p, at
                    cp/pt.c:26813
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

g++-11.0.1-alpha20210418 snapshot (g:b412ce8e961052e6becea3bc783a53e1d5feaa0f)
ICEs when compiling the following testcase, reduced from
test/SemaCXX/lambda-expressions.cpp from the clang 11.1.0 test suite:

template <typename... Ts>
void
local_class ()
{
  int { []{ struct ZZ : Ts {}; }... };
}

template // <>
void
local_class<int> ();

% g++-11.0.1 -c xhrah4q6.cpp
xhrah4q6.cpp: In instantiation of 'struct local_class<int>()::<lambda()>::ZZ':
xhrah4q6.cpp:5:29:   required from 'void local_class() [with Ts = {int}]'
xhrah4q6.cpp:10:19:   required from here
xhrah4q6.cpp:5:20: internal compiler error: in dependent_type_p, at
cp/pt.c:26813
    5 |   int { []{ struct ZZ : Ts {}; }... };
      |                    ^~
0x69d8fd dependent_type_p(tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:26813
0x983e58 xref_basetypes(tree_node*, tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/decl.c:15434
0xad9331 instantiate_class_template_1
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:11922
0xadadb2 instantiate_class_template(tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:12287
0xb272e9 complete_type(tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/typeck.c:143
0xab048d tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18737
0xab0af1 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18238
0xab05df tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18589
0xadbabe tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18223
0xadbabe tsubst_lambda_expr(tree_node*, tree_node*, int, tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:19540
0xaa5284 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:20891
0xaadfd8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:19198
0xaad864 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18223
0xaad864 gen_elem_of_pack_expansion_instantiation
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:12562
0xaad864 tsubst_pack_expansion(tree_node*, tree_node*, int, tree_node*)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:13227
0xaa5be3 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:20735
0xaadfd8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:19198
0xab038c tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18268
0xab0af1 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18238
0xab05df tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
       
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210426/work/gcc-11-20210426/gcc/cp/pt.c:18589

[Bug c++/100282] [11/12 Regression] ICE in dependent_type_p, at cp/pt.c:26813

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
   Target Milestone|---                         |11.2

[Bug c++/100282] [11/12 Regression] ICE in dependent_type_p, at cp/pt.c:26813

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mpolacek at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2021-04-28

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Confirmed.

[Bug c++/100282] [11/12 Regression] ICE with local class in lambda in pack expansion

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

--- Comment #2 from Arseny Solokha <asolokha at gmx dot com> ---
g++-12.0.0-alpha20210530 snapshot (g:a0a7adeea31918deefb053a9a15257af94aecfaf)
rejects the testcase w/o ICE.

[Bug c++/100282] [11/12 Regression] ICE with local class in lambda in pack expansion

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.2                        |11.3

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 11.2 is being released, retargeting bugs to GCC 11.3

[Bug c++/100282] [11/12 Regression] ICE with local class in lambda in pack expansion

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

--- Comment #4 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:4d2efec9f229c2e2e7cb6c3f06beb4c3e9d244a1

commit r12-6909-g4d2efec9f229c2e2e7cb6c3f06beb4c3e9d244a1
Author: Jason Merrill <jason@redhat.com>
Date:   Thu Jan 27 17:46:43 2022 -0500

    c++: pack in enumerator in lambda [PR100198]

    The GCC 8 lambda overhaul fixed most uses of lambdas in pack expansions,
but
    local enums and classes within such lambdas that depend on parameter packs
    are still broken.  For now, give a sorry instead of an ICE or incorrect
    error.

            PR c++/100198
            PR c++/100030
            PR c++/100282

    gcc/cp/ChangeLog:

            * parser.cc (cp_parser_enumerator_definition): Sorry on parameter
            pack in lambda.
            (cp_parser_class_head): And in class attributes.
            * pt.cc (check_for_bare_parameter_packs): Sorry instead of error
            in lambda.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp0x/lambda/lambda-variadic13.C: Accept the sorry
            as well as the correct error.
            * g++.dg/cpp0x/lambda/lambda-variadic14.C: Likewise.
            * g++.dg/cpp0x/lambda/lambda-variadic14a.C: New test.
            * g++.dg/cpp0x/lambda/lambda-variadic15.C: New test.
            * g++.dg/cpp0x/lambda/lambda-variadic16.C: New test.

[Bug c++/100282] local class in lambda in pack expansion

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.3                        |---
           Keywords|ice-on-invalid-code         |rejects-valid
            Summary|[11/12 Regression] ICE with |local class in lambda in
                   |local class in lambda in    |pack expansion
                   |pack expansion              |

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> ---
I can't reproduce the ICE with the top of any branch; leaving the PR open for
the rejects-valid bug.

[Bug c++/100282] local class in lambda in pack expansion

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100282

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hewillk at gmail dot com

--- Comment #6 from Jason Merrill <jason at gcc dot gnu.org> ---
*** Bug 103428 has been marked as a duplicate of this bug. ***