[Bug c++/110031] New: ICE: error reporting routines re-entered on non-type template argument

[Bug c++/110031] New: ICE: error reporting routines re-entered on non-type template argument

[stevenxia990430 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

            Bug ID: 110031
           Summary: ICE: error reporting routines re-entered on non-type
                    template argument
           Product: gcc
           Version: 12.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: stevenxia990430 at gmail dot com
  Target Milestone: ---

The following program produces internal compiler error: error reporting
routines re-entered. Checked on clang and it was rejected as invalid code.
Tested on gcc trunk. 


To quickly reproduce: https://gcc.godbolt.org/z/ex14EKeox
```
#include <type_traits>

#include <iostream>
template <typename T>
constexpr void print_type()
{
  std::cout << "Type: " << typeid(T).name();
}
template <typename T, std::enable_if_t<std::is_literal_type_v<std::decay_t<T>>,
int> = 0>
struct A {
  A(T &&)
  {
  }
};

template <typename T>
struct A<T> {
  A(T &&) = delete;
};

int main(void)
{
  A a{5.3};
  return 0;
}
```

Note, if we comment out the A a{5.3}; line in main function, gcc-trunk actually
accept this code (compiles) however it is rejected by clang. Might be related
to  this: bug109390

[Bug c++/110031] ICE: error reporting routines re-entered on non-type template argument

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Self-contained testcase without any headers:
```
template <typename T>
[[deprecated]] 
inline constexpr bool t = true ;

template <bool a>
struct enableif;

template<>
struct enableif<true>
{
        using y = int;
};
template <bool a>
using enableif_t = enableif<a>::y;

template <typename T, enableif_t<t<T>> = 0>
struct A {  A(T &&)  {  }};

template <typename T>
struct A<T> {
  A(T &&) = delete;
};

int main(void)
{
  A<double> a{5.3};
  return 0;
}
```

[Bug c++/110031] [10/11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Target Milestone|---                         |10.5
   Last reconfirmed|                            |2023-05-30
      Known to work|                            |7.1.0
            Summary|ICE: error reporting        |[10/11/12/13/14 Regression]
                   |routines re-entered on      |ICE with deprecated
                   |non-type template argument  |attribute and NTTP and
                   |and C++20+                  |diagnostic for deprecated
                   |                            |printed out so much
           Keywords|                            |diagnostic, ice-checking
             Status|UNCONFIRMED                 |NEW
      Known to fail|                            |8.1.0

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Better testcase which fails with -std=c++17 even earlier than GCC 8.
```
template <typename T>
[[deprecated]] 
inline constexpr bool t = true ;

template <bool a>
struct enableif;

template<>
struct enableif<true>
{
        using y = int;
};
template <bool a>
using enableif_t = typename enableif<a>::y;

template <typename T, enableif_t<t<T>> = 0>
struct A {  A(T &&)  {  }};

template <typename T>
struct A<T> {
  A(T &&) = delete;
  A() = delete;
};

int main(void)
{
  A<double> a(5.3);
  return 0;
}
```

[Bug c++/110031] [10/11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[stevenxia990430 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

--- Comment #3 from Steven Xia <stevenxia990430 at gmail dot com> ---
Thanks for the improved testcase.

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

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

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 10 branch is being closed.

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P4
           Keywords|                            |ice-on-invalid-code

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P4                          |P2
           Keywords|                            |accepts-invalid

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

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

--- Comment #5 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Started with r8-4678-g6296cf8e099aae:

commit 6296cf8e099aae43c86a773f93d83a19df85d7e7
Author: Jason Merrill <jason@redhat.com>
Date:   Thu Nov 16 15:13:48 2017 -0500

    PR c++/79092 - non-type args of different types are different

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

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

[Bug c++/110031] [11/12/13/14 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Marek Polacek <mpolacek@gcc.gnu.org>:

https://gcc.gnu.org/g:9f915684624413f96e1a5ffada398ccd1c533e38

commit r14-9364-g9f915684624413f96e1a5ffada398ccd1c533e38
Author: Marek Polacek <polacek@redhat.com>
Date:   Mon Mar 4 12:35:18 2024 -0500

    c++: ICE with variable template and [[deprecated]] [PR110031]

    lookup_and_finish_template_variable already has and uses the complain
    parameter but it is not passing it down to mark_used so we got the
    default tf_warning_or_error, which causes various problems when
    lookup_and_finish_template_variable gets called with complain=tf_none.

            PR c++/110031

    gcc/cp/ChangeLog:

            * pt.cc (lookup_and_finish_template_variable): Pass complain to
            mark_used.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp1z/inline-var11.C: New test.

[Bug c++/110031] [11/12/13 Regression] ICE with deprecated attribute and NTTP and diagnostic for deprecated printed out so much

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110031

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[11/12/13/14 Regression]    |[11/12/13 Regression] ICE
                   |ICE with deprecated         |with deprecated attribute
                   |attribute and NTTP and      |and NTTP and diagnostic for
                   |diagnostic for deprecated   |deprecated printed out so
                   |printed out so much         |much

--- Comment #7 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Fixed on trunk so far.