[Bug c++/98800] New: ICE on invalid use of non-static member function in trailing return type since r251438

[Bug c++/98800] New: ICE on invalid use of non-static member function in trailing return type since r251438

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

            Bug ID: 98800
           Summary: ICE on invalid use of non-static member function in
                    trailing return type since r251438
           Product: gcc
           Version: 10.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ppalka at gcc dot gnu.org
  Target Milestone: ---

This invalid testcase is just a minor variant of PR97399#c4 where the member
function is_integral has been made non-static.

$ cat testcase.C
template <bool> struct enable_if_t {};
struct tmp {
  template <class>   constexpr bool is_integral();
  template <class E> static auto func() -> enable_if_t<is_integral<E>()>;
};
template <class> constexpr bool tmp::is_integral() { return true; }
int main() { tmp::func<int>(); }

$ g++ testcase.C
testcase.C: In substitution of ‘template<class T> static
enable_if_t<((tmp*)this)->is_integral<T>()> tmp::f() [with T = int]’:
testcase.C:21:15:   required from here
testcase.C:9:39: internal compiler error: in tsubst_copy, at cp/pt.c:16393
    9 |     -> enable_if_t<tmp::is_integral<T>()>; // { dg-message "in template
argument" }
      |                    ~~~~~~~~~~~~~~~~~~~^~

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|ICE on invalid use of       |[8/9/10/11 Regression] ICE
                   |non-static member function  |on invalid use of
                   |in trailing return type     |non-static member function
                   |since r251438               |in trailing return type
                   |                            |since r8-2724
           Keywords|                            |ice-on-invalid-code
                 CC|                            |jason at gcc dot gnu.org
      Known to fail|                            |10.2.0, 11.0, 8.4.0, 9.3.0
      Known to work|                            |7.5.0

--- Comment #1 from Patrick Palka <ppalka at gcc dot gnu.org> ---
GCC 7.5 rejects with:

<source>: In function 'int main()':
<source>:7:29: error: no matching function for call to 'tmp::func<int>()'
 int main() { tmp::func<int>(); }
                             ^
<source>:4:34: note: candidate: template<class E> static
enable_if_t<is_integral<E>()> tmp::func()
   template <class E> static auto func() -> enable_if_t<is_integral<E>()>;
                                  ^~~~
<source>:4:34: note:   template argument deduction/substitution failed:
<source>: In substitution of 'template<class E> static
enable_if_t<is_integral<E>()> tmp::func() [with E = int]':
<source>:7:29:   required from here
<source>:4:70: error: cannot call member function 'constexpr bool
tmp::is_integral() [with <template-parameter-1-1> = int]' without object
   template <class E> static auto func() -> enable_if_t<is_integral<E>()>;
                                                        ~~~~~~~~~~~~~~^~

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

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

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-01-25
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
                 CC|                            |mpolacek at gcc dot gnu.org

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Confirmed.

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> ---
I'm getting a correct (if obscure) error message before the ICE:

wa.C:4:71: error: use of ‘this’ in a constant expression
    4 | template <class E> static auto func() -> enable_if_t<is_integral<E>()>;
      |                                                                     ^

wa.C:4: confused by earlier errors, bailing out

are you still not?

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P2                          |P4
           Keywords|                            |error-recovery

--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I can see that error message now.  So, error-recovery and I suspect P4.

[Bug c++/98800] [8/9/10/11 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

--- Comment #5 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:82198676c80764ca7cf05f891afaee83b9179dd1

commit r11-8118-g82198676c80764ca7cf05f891afaee83b9179dd1
Author: Jason Merrill <jason@redhat.com>
Date:   Sat Apr 10 10:55:58 2021 -0400

    c++: ICE with invalid use of 'this' with static memfn [PR98800]

    Here instantiation of the fake 'this' parameter we used when parsing the
    trailing return type of func() was failing because there is no actual
'this'
    parameter in the instantiation.  For PR97399 I told Patrick to do the
'this'
    injection even for statics, but now I think I was wrong; the out-of-class
    definition case I was concerned about does not break with this patch.  And
    we don't set current_class_ptr in the body of a static member function.

    And the OMP code should continue to parse 'this' and complain about it
    rather than give a syntax error.

    gcc/cp/ChangeLog:

            PR c++/98800
            PR c++/97399
            * parser.c (cp_parser_direct_declarator): Don't
            inject_this_parameter if static_p.
            (cp_parser_omp_var_list_no_open): Parse 'this' even if
            current_class_ptr isn't set for a better diagnostic.

    gcc/testsuite/ChangeLog:

            PR c++/98800
            * g++.dg/gomp/this-1.C: Adjust diagnostic.
            * g++.dg/cpp0x/constexpr-this1.C: New test.

[Bug c++/98800] [9/10/11/12 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

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

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 8 branch is being closed.

[Bug c++/98800] [9/10/11/12 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

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

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9.4 is being released, retargeting bugs to GCC 9.5.

[Bug c++/98800] [10/11/12/13 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

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

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 9 branch is being closed

[Bug c++/98800] [10/11/12/13 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

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

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 10.4 is being released, retargeting bugs to GCC 10.5.

[Bug c++/98800] [11/12/13/14 Regression] ICE on invalid use of non-static member function in trailing return type since r8-2724

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98800

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|10.5                        |11.5

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 10 branch is being closed.