<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/67551>67551</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] [ranges] sized_range of iota_view<short, short>
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          jonathan-hopkins
      </td>
    </tr>
</table>

<pre>
    Hi. The following code, when compiled with libc++, is unable to deduce the correct size type of iota_view. Changing short to a different integral type generates no errors.

```
#include <ranges>
#include <numeric>

int main() {
 static_assert(std::ranges::sized_range<std::ranges::iota_view<short, short>>, "short");
}
```

clang output:
```
In file included from <source>:1:
In file included from /opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/ranges:353:
In file included from /opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/drop_view.h:30:
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/iota_view.h:368:9: error: 'auto' in return type deduced as 'int' here but deduced as '__make_unsigned_t<int>' (aka 'unsigned int') in earlier return statement
 return std::__to_unsigned_like(__bound_sentinel_) - std::__to_unsigned_like(__value_);
 ^
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/size.h:55:29: note: in instantiation of member function 'std::ranges::iota_view<short, short>::size' requested here
    { _LIBCPP_AUTO_CAST(__t.size()) } -> __integer_like;
 ^
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/size.h:55:7: note: in instantiation of requirement here
    { _LIBCPP_AUTO_CAST(__t.size()) } -> __integer_like;
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__utility/auto_cast.h:20:33: note: expanded from macro '_LIBCPP_AUTO_CAST'
#define _LIBCPP_AUTO_CAST(expr) static_cast<typename decay<decltype((expr))>::type>(expr)
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/size.h:54:3: note: while substituting template arguments into constraint expression here
  requires(_Tp&& __t) {
 ^~~~~~~~~~~~~~~~~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/size.h:92:13: note: while checking the satisfaction of concept '__member_size<std::ranges::iota_view<short, short> &>' requested here
 template <__member_size _Tp>
 ^
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/size.h:92:13: note: while substituting template arguments into constraint expression here
  template <__member_size _Tp>
 ^~~~~~~~~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/concepts.h:78:60: note: while checking constraint satisfaction for template 'operator()<std::ranges::iota_view<short, short> &>' required here
 concept sized_range = range<_Tp> && requires(_Tp& __t) { ranges::size(__t); };
 ^~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/concepts.h:78:60: note: in instantiation of function template specialization 'std::ranges::__size::__fn::operator()<std::ranges::iota_view<short, short> &>' requested here
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/concepts.h:78:60: note: in instantiation of requirement here
  concept sized_range = range<_Tp> && requires(_Tp& __t) { ranges::size(__t); };
 ^~~~~~~~~~~~~~~~~
/opt/compiler-explorer/clang-16.0.0/bin/../include/c++/v1/__ranges/concepts.h:78:39: note: while substituting template arguments into constraint expression here
  concept sized_range = range<_Tp> && requires(_Tp& __t) { ranges::size(__t); };
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
<source>:5:19: note: while checking the satisfaction of concept 'sized_range<std::ranges::iota_view<short, short>>' requested here
 static_assert(std::ranges::sized_range<std::ranges::iota_view<short, short>>, "short");
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
Compiler returned: 1
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzMWF1v2zoS_TX0y8CGTVqS_eAHx46xBRbYApt9FmhqZLGRSC1JJU0f7m-_GEp2nNRpi958NDBshR8azZkzZ0aU3uuDQVyx5Iol25HsQmXd6os1MlTSjCvb3mrjR3tbPKz-pSdwUyGUtq7tvTYHULZAxjdwX6EBZZtW11jAvQ4V1HqvGL-Knw1oD52R-xohWCiw6BRCqBCUdQ5VAK-_IYSHFsGWoG2Q-Z3G-wlsKmkOZMlX1gXaLKHQZYkOTQBtAh6crPudBzToZEAPxgI6Z52fsOmWTdfDdzodPv2_XGij6q5AYGLjpDmgZ-L60qTpGnRaPc7Gb20CNFIbxheML4FlV_04-CCDVrn0Hl1gfOFDwcSaifXRCF2Tx0UeR5jYXFxywoEWkP-EZH8hrunDN8A4H6Y440smhmdg2fay0_Fb1dIcwHah7QKZurTyk4FS1wgDDAWUzjYEhredUxifYD077X5hOd_ZNjC-G7jhxvi1ra1DR2P0FONZOplOpozv9oTkbjJhfDfchNYcKbS7mzG-O6EjEvHOpvN8MM53hbNtz8-KHmX6COHb2XzMiWgzXTCxXjKx7olOF4xnsguW8Qy0AYehc6ZPjD7fCpCeFmkTaE2FDmHfhWezed7IW8w7E3WhyAMTG9pBbMuA8YW8lbTuuAD621ECaAMoXa3RHa1TImCDJgyJcRoeyJ7nwT6aqvUtMr7I873tTJF7NEEbrHO69_inm-5k3WF-ngPAkus3jwulcQxJkjCx5jEkxgakX21AGx-kCVoGbQ1pW4PNHh2UnVFxiPHsd3L_qCAUFIf_79AHLGJMB98BSJAg__enq83nz_n6fzf_yTfr_95ErMKk30u61UvXFsZMXEOeR0lF1-P6gUhmPwOSvNYusutN_f7rB39vhUkXdK3DA-M7yuhcSR8iMpykRohzaPBrK81J9BqpnI1p_L3_2amyFVhqgxcxwq-tI2SGEkaWmdiQihjZkJIo-cDEpkBV02CE8rgp5t7AzThJmnGa_CVAPwLsCwScE8znKN9XVGB8t_dBhy5QQxKwaWsZEKQ7dMRCT1JoQVnjg5PUHJDr6D0R9pyhA3M9UfKmZTxlPIU8D0-biBeQej8UlpwK_AUYVIXqNkJQIXgZtC-lOqalskZhG4ZSEsUuj0n3Oz0OEDh95bkocqcYMLF5Yg0I2GO39r7q9SJsr8SeX_f5XWkzxN1HDDLqTtLpD6hz5ucTBpXWnXnIM9tSS2_doNmvQCLtnnLoSNizfhyY2MKxM-9RhSFNv8vds8SF5-19X3P6loRqzfd15cPDcqmynnqTUyB8i0rLWn-TP-xZ8iHT--vS9FevH8LnOvCH4fdSZ_KhTPtYLRDLN9PDPwXVn7QtT9-bqcOdXcDkV0vrqxwevFBU_4DTi3_SJp6BPutfjk8HQ8VwHLQZGD-8jyI9PMyenYKMipUolmIpR7iapctkMVvO03RUrVKFYr-Us-U0zaalmO1TIZOsnCupyplIcKRXfMrFdMmzGU-yeTqZp4tpxrNsMZvLRCjF5lNspK4ndX3XTKw7jLT3Ha7SLElmo1rusfbxQI7z81M0zpLtyK1o03jfHTybT2vtg3-8TdChjkd5Z9uSLbDkaghMsn2SJ-dnbZeiNOpcvapCaGNI-Y7x3UGHqttPlG0Y35Hh4WfcOvsFFQlKdIZ0IPrzdwAAAP__S8R9oQ">