I believe, this caused failure
21_strings/basic_string/requirements/dr438/constructor.c in C++20 mode::
In file included from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/functions.h:39,
from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_sequence.h:34,
from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/string:37,
from
/home/tkaminsk/src/gcc/libstdc++-v3/testsuite/21_strings/basic_string/requirements/dr438/constructor.cc:23:
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/helper_functions.h:
In instantiation of 'constexpr bool
__gnu_debug::__valid_range(_InputIterator, _InputIterator) [with
_InputIterator = int]':
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/functions.h:65:
required from 'constexpr _InputIterator
__gnu_debug::__check_valid_range(const _InputIterator&, const
_InputIterator&, const char*, unsigned int, const char*) [with
_InputIterator = int]'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/string:238:
required from '__gnu_debug::basic_string<_CharT, _Traits,
_Allocator>::basic_string(_InputIterator, _InputIterator, const
_Allocator&) [with _InputIterator = int; _CharT = char; _Traits =
std::char_traits<char>; _Allocator = std::allocator<char>]'
/home/tkaminsk/src/gcc/libstdc++-v3/testsuite/21_strings/basic_string/requirements/dr438/constructor.cc:28:
required from here
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/helper_functions.h:212:
error: no matching function for call to '__iterator_category(int&)'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/helper_functions.h:212:
note: there is 1 candidate
In file included from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_construct.h:61,
from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/char_traits.h:59,
from
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/string:45,
from
/home/tkaminsk/src/gcc/libstdc++-v3/testsuite/21_strings/basic_string/requirements/dr438/constructor.cc:22:
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_iterator_base_types.h:241:
note: candidate 1: 'template<class _Iter> constexpr typename
std::iterator_traits<_Iterator>::iterator_category
std::__iterator_category(const _Iter&)'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_iterator_base_types.h:241:
note: template argument deduction/substitution failed:
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_iterator_base_types.h:
In substitution of 'template<class _Iter> constexpr typename
std::iterator_traits<_Iterator>::iterator_category
std::__iterator_category(const _Iter&) [with _Iter = int]':
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/helper_functions.h:212:
required from 'constexpr bool __gnu_debug::__valid_range(_InputIterator,
_InputIterator) [with _InputIterator = int]'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/functions.h:65:
required from 'constexpr _InputIterator
__gnu_debug::__check_valid_range(const _InputIterator&, const
_InputIterator&, const char*, unsigned int, const char*) [with
_InputIterator = int]'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/string:238:
required from '__gnu_debug::basic_string<_CharT, _Traits,
_Allocator>::basic_string(_InputIterator, _InputIterator, const
_Allocator&) [with _InputIterator = int; _CharT = char; _Traits =
std::char_traits<char>; _Allocator = std::allocator<char>]'
/home/tkaminsk/src/gcc/libstdc++-v3/testsuite/21_strings/basic_string/requirements/dr438/constructor.cc:28:
required from here
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_iterator_base_types.h:241:
error: no type named 'iterator_category' in 'struct
std::iterator_traits<int>'
compiler exited with status 1
FAIL: 21_strings/basic_string/requirements/dr438/constructor.cc
-std=gnu++20 (test for excess errors)
Excess errors:
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/helper_functions.h:212:
error: no matching function for call to '__iterator_category(int&)'
/home/tkaminsk/build/gcc/16/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_iterator_base_types.h:241:
error: no type named 'iterator_category' in 'struct
std::iterator_traits<int>'
On Mon, Mar 2, 2026 at 7:00 AM François Dumont <[email protected]> wrote:
> Hi
>
> libstdc++: [_GLIBCXX_DEBUG][__cplusplus >= 201103L] Remove useless
> workaround
>
> Starting with C++11 we leverage on template parameter requirement
> to prevent
> instantiation of methods taking iterators with invalid types.
> So the _GLIBCXX_DEBUG mode do not need to check for potential
> ambiguity between
> integer type and iterator type anymore.
>
> libstdc++-v3/ChangeLog:
>
> * include/debug/functions.h
> [__cplusplus >= 201103L](__foreign_iterator_aux): Remove.
> [__cplusplus >= 201103L](__foreign_iterator): Adapt to use
> __foreign_iterator_aux2.
> * include/debug/helper_functions.h
> [__cplusplus >= 201103L]: Remove include
> bits/cpp_type_traits.h.
> [__cplusplus >= 201103L](_Distance_traits<_Integral,
> std::__true_type>): Remove.
> [__cplusplus >= 201103L](__valid_range_aux(_Integral,
> _Integral, std::__true_type)):
> Remove.
> [__cplusplus >= 201103L](__valid_range_aux(_Iterator,
> _Iterator, std::__false_type)):
> Remove.
> [__cplusplus >= 201103L]
> (__valid_range_aux(_Integral, _Integral,
> _Distance_traits<_Integral>::__type&,
> std::__true_type)): Remove.
> [__cplusplus >= 201103L]
> (__valid_range_aux(_Iterator, _Iterator,
> _Distance_traits<_Iterator>::__type&,
> std::__false_type)): Remove.
> [__cplusplus >= 201103L](__valid_range(_Iterator,
> _Iterator)): Adapt.
> [__cplusplus >= 201103L]
> (__valid_range(_Iterator, _Iterator,
> _Distance_traits<_Iterator>::__type&)): Adapt.
>
> Tested under Linux x64 _GLIBCXX_DEBUG mode.
>
> Ok to commit ?
>
> François
>
>
