https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120969
Bug ID: 120969
Summary: two consecutive '[' shall only introduce an attribute
before '[' token
Product: gcc
Version: 14.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: f.heckenb...@fh-soft.de
Target Milestone: ---
(see output below)
- First of all, GCC is complaining about its own standard library here!
- The first message doesn't seem to make much sense at all, attribute only
before '[' token, what? (The actual usage looks like a perfectly cromulent
attribute to me, anyway. That's why I'm reporting this against the compiler,
not the library, as I suspect the bug is in the compiler.)
- The errors only appear with "-fconcepts-ts" which I only use because GCC
suggested (required) me to
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120917). If someone could comment
on my proposed workaround there
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120917#c17), maybe I could avoid
using this flag and these errors. (Though even then, the errors seem strange
and worth investigating ...)
% dpkg -l | grep libstdc++
ii libstdc++-14-dev:amd64 14.2.0-19
amd64 GNU Standard C++ Library v3 (development files)
ii libstdc++6:amd64 14.2.0-19
amd64 GNU Standard C++ Library v3
% tail -n+3750 /usr/include/c++/14/format | head -n 7
template<typename... _Tp>
requires (sizeof...(_Tp) == sizeof...(_Args))
[[__gnu__::__always_inline__]]
_Arg_store(_Tp&... __a) noexcept
: _M_args{_S_make_elt(__a)...}
{ }
% cat test.cpp
#include <memory>
% g++ --std="c++23" -Wpedantic -pedantic -pedantic-errors -Wall -Wextra
-fconcepts-ts -c /tmp/test.cpp
cc1plus: note: '-fconcepts-ts' is deprecated and will be removed in GCC 15;
please convert your code to C++20 concepts
In file included from /usr/include/c++/14/ostream:43,
from /usr/include/c++/14/bits/unique_ptr.h:43,
from /usr/include/c++/14/memory:78,
from /tmp/test.cpp:1:
/usr/include/c++/14/format:3753:9: error: two consecutive '[' shall only
introduce an attribute before '[' token
3753 | [[__gnu__::__always_inline__]]
| ^
/usr/include/c++/14/format:4220:5: error: two consecutive '[' shall only
introduce an attribute before '[' token
4220 | [[__gnu__::__always_inline__]]
| ^
/usr/include/c++/14/format:4227:5: error: two consecutive '[' shall only
introduce an attribute before '[' token
4227 | [[__gnu__::__always_inline__]]
| ^
/usr/include/c++/14/format:4234:5: error: two consecutive '[' shall only
introduce an attribute before '[' token
4234 | [[__gnu__::__always_inline__]]
| ^
/usr/include/c++/14/format:4244:5: error: two consecutive '[' shall only
introduce an attribute before '[' token
4244 | [[__gnu__::__always_inline__]]
| ^
/usr/include/c++/14/format: In function 'std::string std::vformat(string_view,
format_args)':
/usr/include/c++/14/format:4258:20: error: no matching function for call to
'vformat_to(std::__format::_Sink_iter<char>, std::string_view&,
std::format_args&)'
4258 | std::vformat_to(__buf.out(), __fmt, __args);
| ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, string_view,
format_args)'
4222 | vformat_to(_Out __out, string_view __fmt, format_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4222:5: note: constraints not satisfied
/usr/include/c++/14/format:4229:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, wstring_view,
wformat_args)'
4229 | vformat_to(_Out __out, wstring_view __fmt, wformat_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4229:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4229:5: note: constraints not satisfied
/usr/include/c++/14/format:4236:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
string_view, format_args)'
4236 | vformat_to(_Out __out, const locale& __loc, string_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4236:5: note: candidate expects 4 arguments, 3
provided
/usr/include/c++/14/format:4246:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
wstring_view, wformat_args)'
4246 | vformat_to(_Out __out, const locale& __loc, wstring_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4246:5: note: candidate expects 4 arguments, 3
provided
/usr/include/c++/14/format: In function 'std::wstring
std::vformat(wstring_view, wformat_args)':
/usr/include/c++/14/format:4268:20: error: no matching function for call to
'vformat_to(std::__format::_Sink_iter<wchar_t>, std::wstring_view&,
std::wformat_args&)'
4268 | std::vformat_to(__buf.out(), __fmt, __args);
| ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, string_view,
format_args)'
4222 | vformat_to(_Out __out, string_view __fmt, format_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4222:5: note: constraints not satisfied
/usr/include/c++/14/format:4229:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, wstring_view,
wformat_args)'
4229 | vformat_to(_Out __out, wstring_view __fmt, wformat_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4229:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4229:5: note: constraints not satisfied
/usr/include/c++/14/format:4236:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
string_view, format_args)'
4236 | vformat_to(_Out __out, const locale& __loc, string_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4236:5: note: candidate expects 4 arguments, 3
provided
/usr/include/c++/14/format:4246:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
wstring_view, wformat_args)'
4246 | vformat_to(_Out __out, const locale& __loc, wstring_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4246:5: note: candidate expects 4 arguments, 3
provided
/usr/include/c++/14/format: In function 'std::string std::vformat(const
locale&, string_view, format_args)':
/usr/include/c++/14/format:4278:20: error: no matching function for call to
'vformat_to(std::__format::_Sink_iter<char>, const std::locale&,
std::string_view&, std::format_args&)'
4278 | std::vformat_to(__buf.out(), __loc, __fmt, __args);
| ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, string_view,
format_args)'
4222 | vformat_to(_Out __out, string_view __fmt, format_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4229:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, wstring_view,
wformat_args)'
4229 | vformat_to(_Out __out, wstring_view __fmt, wformat_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4229:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4236:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
string_view, format_args)'
4236 | vformat_to(_Out __out, const locale& __loc, string_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4236:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4236:5: note: constraints not satisfied
/usr/include/c++/14/format:4246:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
wstring_view, wformat_args)'
4246 | vformat_to(_Out __out, const locale& __loc, wstring_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4246:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4246:5: note: constraints not satisfied
/usr/include/c++/14/format: In function 'std::wstring std::vformat(const
locale&, wstring_view, wformat_args)':
/usr/include/c++/14/format:4288:20: error: no matching function for call to
'vformat_to(std::__format::_Sink_iter<wchar_t>, const std::locale&,
std::wstring_view&, std::wformat_args&)'
4288 | std::vformat_to(__buf.out(), __loc, __fmt, __args);
| ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, string_view,
format_args)'
4222 | vformat_to(_Out __out, string_view __fmt, format_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4229:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, wstring_view,
wformat_args)'
4229 | vformat_to(_Out __out, wstring_view __fmt, wformat_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4229:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4236:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
string_view, format_args)'
4236 | vformat_to(_Out __out, const locale& __loc, string_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4236:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4236:5: note: constraints not satisfied
/usr/include/c++/14/format:4246:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
wstring_view, wformat_args)'
4246 | vformat_to(_Out __out, const locale& __loc, wstring_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4246:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4246:5: note: constraints not satisfied
/usr/include/c++/14/ostream: In function 'void std::vprint_nonunicode(ostream&,
string_view, format_args)':
/usr/include/c++/14/ostream:892:24: error: no matching function for call to
'vformat_to(std::__format::_Sink_iter<char>, std::locale, std::string_view&,
std::format_args&)'
892 | std::vformat_to(__buf.out(), __os.getloc(), __fmt, __args);
| ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, string_view,
format_args)'
4222 | vformat_to(_Out __out, string_view __fmt, format_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4222:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4229:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, wstring_view,
wformat_args)'
4229 | vformat_to(_Out __out, wstring_view __fmt, wformat_args __args)
| ^~~~~~~~~~
/usr/include/c++/14/format:4229:5: note: candidate expects 3 arguments, 4
provided
/usr/include/c++/14/format:4236:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
string_view, format_args)'
4236 | vformat_to(_Out __out, const locale& __loc, string_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4236:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4236:5: note: constraints not satisfied
/usr/include/c++/14/format:4246:5: note: candidate: 'template<class _Out>
requires <erroneous-expression> _Out std::vformat_to(_Out, const locale&,
wstring_view, wformat_args)'
4246 | vformat_to(_Out __out, const locale& __loc, wstring_view __fmt,
| ^~~~~~~~~~
/usr/include/c++/14/format:4246:5: note: template argument
deduction/substitution failed:
/usr/include/c++/14/format:4246:5: note: constraints not satisfied
