<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/75042>75042</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] `std::regex` `$` alone with `match_default` doesn't match `[last, last)` 
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          zufuliu
      </td>
    </tr>
</table>

<pre>
    ```c++
#include <string>
#include <regex>
#include <iostream>
using namespace std;

int main() {
    string s = "ab";
    regex re("$");
    cout << "$" << endl;
    cout << regex_search(s, re, regex_constants::match_default) << endl;
    cout << regex_search(s, re, regex_constants::match_not_eol) << endl;
    return 0;
}
```

llvm-mingw 17.0.6: 
```
D:\notepad2>clang++ -std=c++17 -Wall -Wextra test2.cpp

D:\notepad2>a.exe
$
0
0
```

GCC 13.2.0:
```
D:\notepad2>g++ -std=c++17 -Wall -Wextra test2.cpp

D:\notepad2>a.exe
$
1
0
```

MSVC 2022:
```
D:\notepad2>cl /nologo /EHsc /std:c++17 /W4 test2.cpp
test2.cpp

D:\notepad2>test2.exe
$
1
0
```
</pre>
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