[Bug libstdc++/105128] New: source_location compile error for clang

[Bug libstdc++/105128] New: source_location compile error for clang

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

            Bug ID: 105128
           Summary: source_location compile error for clang
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: unlvsur at live dot com
  Target Milestone: ---

It looks like clang just added source_location implementation but the built-in
looks different. Unfortunately, libcxx does not implement this either at this
point. However, the testsuite probably tells how clang implements this.

https://github.com/llvm/llvm-project/blob/d61487490022aaacc34249475fac3e208c7d767e/clang/test/CodeGenCXX/builtin-source-location.cpp

#include<source_location>

int main()
{
        std::source_location::current();
}

clang++ -o sourcelocation sourcelocation.cc -Ofast -std=c++2b -s -flto=thin
-fuse-ld=lld
In file included from sourcelocation.cc:1:
/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/12.0.1/../../../../include/c++/12.0.1/source_location:46:41:
error: 'std::source_location::__impl' was not found; it must be defined before
'__builtin_source_location' is called
    using __builtin_ret_type = decltype(__builtin_source_location());
                                        ^
/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/12.0.1/../../../../include/c++/12.0.1/source_location:52:13:
error: unknown type name '__builtin_ret_type'
    current(__builtin_ret_type __p = __builtin_source_location()) noexcept
            ^
/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/12.0.1/../../../../include/c++/12.0.1/source_location:52:32:
error: cannot initialize a parameter of type 'int' with an rvalue of type
'const std::source_location::__impl *'
    current(__builtin_ret_type __p = __builtin_source_location()) noexcept
                               ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/local/bin/../lib/gcc/x86_64-pc-linux-gnu/12.0.1/../../../../include/c++/12.0.1/source_location:52:32:
note: passing argument to parameter '__p' here
3 errors generated.

[Bug libstdc++/105128] source_location compile error for latest clang 15

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

--- Comment #1 from cqwrteur <unlvsur at live dot com> ---
Created attachment 52736
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52736&action=edit
Modified source_location header that works on both gcc and clang

It looks like clang requires __impl to be defined before
__builtin_source_location() call. Just change the location for where it should
be defined and it works.

Can we fix it?

[Bug libstdc++/105128] source_location compile error for latest clang 15

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

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

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

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 52738
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52738&action=edit
gcc12-pr105128.patch

So like this untested patch?
Can test it with gcc, but don't have a new enough clang around.

[Bug libstdc++/105128] source_location compile error for latest clang 15

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

--- Comment #3 from cqwrteur <unlvsur at live dot com> ---
(In reply to Jakub Jelinek from comment #2)
> Created attachment 52738 [details]
> gcc12-pr105128.patch
> 
> So like this untested patch?
> Can test it with gcc, but don't have a new enough clang around.

yes, it should work on clang.

[Bug libstdc++/105128] source_location compile error for latest clang 15

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:2a82301d409d3aa0e0b3b884e4c6daeaa0486d6b

commit r12-7968-g2a82301d409d3aa0e0b3b884e4c6daeaa0486d6b
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Apr 2 12:49:38 2022 +0200

    libstdc++: Tweak source_location for clang trunk [PR105128]

    Apparently clang trunk implemented __builtin_source_location(), but the
    using __builtin_ret_type = decltype(__builtin_source_location());
    which has been added for it isn't enough, they also need the
    std::source_location::__impl class to be defined (but incomplete seems
    to be good enough) before the builtin is used.

    The following has been tested on godbolt with clang trunk (old version
    fails with
    error: 'std::source_location::__impl' was not found; it must be defined
before '__builtin_source_location' is called
    and some follow-up errors), getting back to just void * instead of
    __builtin_ret_type and commenting out using doesn't work either and
    just struct __impl; before using __builtin_ret_type doesn't work too.

    2022-04-02  Jakub Jelinek  <jakub@redhat.com>

            PR libstdc++/105128
            * include/std/source_location (std::source_location::__impl): Move
            definition before using __builtin_ret_type.

[Bug libstdc++/105128] source_location compile error for latest clang 15

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

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

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

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed.

[Bug libstdc++/105128] source_location compile error for latest clang 15

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jonathan Wakely
<redi@gcc.gnu.org>:

https://gcc.gnu.org/g:16946c7c823c2d6531ac272d31d68d95d9c30ddd

commit r11-10116-g16946c7c823c2d6531ac272d31d68d95d9c30ddd
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Apr 2 12:49:38 2022 +0200

    libstdc++: Tweak source_location for clang trunk [PR105128]

    Apparently clang trunk implemented __builtin_source_location(), but the
    using __builtin_ret_type = decltype(__builtin_source_location());
    which has been added for it isn't enough, they also need the
    std::source_location::__impl class to be defined (but incomplete seems
    to be good enough) before the builtin is used.

    The following has been tested on godbolt with clang trunk (old version
    fails with
    error: 'std::source_location::__impl' was not found; it must be defined
before '__builtin_source_location' is called
    and some follow-up errors), getting back to just void * instead of
    __builtin_ret_type and commenting out using doesn't work either and
    just struct __impl; before using __builtin_ret_type doesn't work too.

    2022-04-02  Jakub Jelinek  <jakub@redhat.com>

            PR libstdc++/105128
            * include/std/source_location (std::source_location::__impl): Move
            definition before using __builtin_ret_type.

    (cherry picked from commit 2a82301d409d3aa0e0b3b884e4c6daeaa0486d6b)

[Bug libstdc++/105128] source_location compile error for latest clang 15

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105128

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.4

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Backported for 11.4