[Bug c++/96623] New: [10/11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[Bug c++/96623] New: [10/11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[haoxintu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

            Bug ID: 96623
           Summary: [10/11 Regression] ICE in inject_parm_decls, at
                    cp/parser.c:23893
           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: haoxintu at gmail dot com
  Target Milestone: ---

Input:
//small.cc
struct A{ 
    void a(){
        struct B {  
            void b () noexcept();
            };
    }
};

Command:
g++ small.cc

Output:
small.cc: In member function ‘void A::a()’:
small.cc:5:25: internal compiler error: in inject_parm_decls, at
cp/parser.c:23893
    5 |                         };
      |                         ^
0x67450f inject_parm_decls
        ../../gcc/cp/parser.c:23893
0x67450f cp_parser_class_specifier_1
        ../../gcc/cp/parser.c:24239
0x9d3143 cp_parser_class_specifier
        ../../gcc/cp/parser.c:24308
0x9d3143 cp_parser_type_specifier
        ../../gcc/cp/parser.c:17811
0x9d40be cp_parser_decl_specifier_seq
        ../../gcc/cp/parser.c:14436
0x9d4e71 cp_parser_simple_declaration
        ../../gcc/cp/parser.c:13690
0x9d6fdd cp_parser_declaration_statement
        ../../gcc/cp/parser.c:13249
0x9d7c67 cp_parser_statement
        ../../gcc/cp/parser.c:11555
0x9d8ccd cp_parser_statement_seq_opt
        ../../gcc/cp/parser.c:11921
0x9d8da8 cp_parser_compound_statement
        ../../gcc/cp/parser.c:11871
0x9f0ee5 cp_parser_function_body
        ../../gcc/cp/parser.c:23170
0x9f0ee5 cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc/cp/parser.c:23221
0x9f4510 cp_parser_function_definition_after_declarator
        ../../gcc/cp/parser.c:29117
0x9f590c cp_parser_late_parsing_for_member
        ../../gcc/cp/parser.c:30019
0x9d225b cp_parser_class_specifier_1
        ../../gcc/cp/parser.c:24284
0x9d3143 cp_parser_class_specifier
        ../../gcc/cp/parser.c:24308
0x9d3143 cp_parser_type_specifier
        ../../gcc/cp/parser.c:17811
0x9d40be cp_parser_decl_specifier_seq
        ../../gcc/cp/parser.c:14436
0x9d4e71 cp_parser_simple_declaration
        ../../gcc/cp/parser.c:13690
0xa002fe cp_parser_declaration
        ../../gcc/cp/parser.c:13510
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

GCC-10 compiles this code ok, and I test in GCC-trunk-20200808.

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11 Regression] ICE in   |[11 Regression] ICE in
                   |inject_parm_decls, at       |inject_parm_decls, at
                   |cp/parser.c:23893           |cp/parser.c:23893
                 CC|                            |mpolacek at gcc dot gnu.org
   Target Milestone|---                         |11.0
   Last reconfirmed|                            |2020-08-18
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
11 Regression, started with r11-289.

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
We should have rejected "noexcept()".

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Keywords|ice-on-invalid-code         |ice-on-valid-code
           Assignee|unassigned at gcc dot gnu.org      |mpolacek at gcc dot gnu.org

--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
This one is valid:

constexpr int x = 0;
struct A { 
  void foo () {
    struct B {
      void bar () noexcept(x);
    };
  }
};

Doesn't happen when we don't delay the noexcept-specifier parsing, so mine.

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
And an extended test to check that various variables are in scope:

constexpr int x = 0;
struct A {
  int a1;
  void foo (int p) {
    int foovar;
    struct B {
      int b1;
      void bar1 () noexcept(x);
      void bar2 () noexcept(noexcept(this->b1));
      void bar3 () noexcept(noexcept(this->b2));
      void bar4 () noexcept(noexcept(a1));
      void bar5 () noexcept(noexcept(a2));
      void bar6 () noexcept(noexcept(b1));
      void bar7 () noexcept(noexcept(b2));
      void bar8 () noexcept(noexcept(foovar));
      void bar9 () noexcept(noexcept(p));
      int b2;
    };
  }
  int a2;
};

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Marek Polacek <mpolacek@gcc.gnu.org>:

https://gcc.gnu.org/g:89100826acec92dfaa6ab8f2646b8053e7dbc67c

commit r11-6874-g89100826acec92dfaa6ab8f2646b8053e7dbc67c
Author: Marek Polacek <polacek@redhat.com>
Date:   Thu Jan 21 16:12:28 2021 -0500

    c++: ICE with noexcept in class in member function [PR96623]

    I discovered very strange code in inject_parm_decls:

       if (args && is_this_parameter (args))
         {
           gcc_checking_assert (current_class_ptr == NULL_TREE);
           current_class_ptr = NULL_TREE;

    We are tripping up on the assert because when we call inject_parm_decls,
    current_class_ptr is set to 'A'.  It was set by inject_this_parameter
    after we've parsed the parameter-declaration-clause of the member
    function foo.  It seems correct to set ccp/ccr to A::B when we're
    late parsing the noexcept-specifiers of bar* functions in B, so that
    this-> does the right thing.  Since inject_parm_decls doesn't expect
    to see non-null ccp/ccr, reset it before calling inject_parm_decls.

    gcc/cp/ChangeLog:

            PR c++/96623
            * parser.c (inject_parm_decls): Remove a redundant assignment.
            (cp_parser_class_specifier_1): Clear current_class_{ptr,ref}
            before calling inject_parm_decls.

    gcc/testsuite/ChangeLog:

            PR c++/96623
            * g++.dg/cpp0x/noexcept64.C: New test.

[Bug c++/96623] [11 Regression] ICE in inject_parm_decls, at cp/parser.c:23893

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96623

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

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

--- Comment #6 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Fixed.