[Bug c++/123147] New: std::chrono::parse does not support wchar_t

[gast128 at hotmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123147

            Bug ID: 123147
           Summary: std::chrono::parse does not support wchar_t
           Product: gcc
           Version: 14.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gast128 at hotmail dot com
  Target Milestone: ---

Hello all,

not 100% sure if it's a bug or not. If we use std::chrono::parse with char it
compiles fine but if we use it with wchar_t it gives an error. msvc accepts the
code. 

Example:

#include <chrono>
#include <sstream>

using ChronoLocalTime  = std::chrono::local_time<std::chrono::microseconds>;

void From(const std::wstring& crstr)
{
    ChronoLocalTime     tpLoc;

    std::wistringstream  isstr{crstr};

    isstr >> std::chrono::parse(L"%FT%T%z", tpLoc);  // error
}


void From(const std::string& crstr)
{
    ChronoLocalTime     tpLoc;

    std::istringstream  isstr{crstr};

    isstr >> std::chrono::parse("%FT%T%z", tpLoc); // ok
}


int main()
{
    return 0;
}

Compile with -std=c++20. In compiler explorer error with 14.2 as 15.2. Error
seems to be chrono_io.h:3844:62: error: conversion from 'basic_string<wchar_t>'
to non-scalar type'. string __str = std::move(__buf).str();