<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/128195>128195</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            diags without usable source location after #127338
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    ```
$ cat repro.cc
class Location {
 public:
  static Location CurrentWithoutFunctionName(
      const char* file_name = __builtin_FILE(),
      int line_number = __builtin_LINE());
};

class NotReachedNoreturnError {
 public:
 explicit NotReachedNoreturnError(
      const Location& location =
 Location::CurrentWithoutFunctionName());

  [[noreturn]] [[clang::nomerge]] [[clang::noinline]] [[clang::not_tail_called]]
 ~NotReachedNoreturnError();
};

#define NOTREACHED() NotReachedNoreturnError()

int f() {
  NOTREACHED();
  return 4;
}

int g() {
  return 4;
  NOTREACHED();
}
```

```
$ out/gn/bin/clang -c repro.cc -Wunreachable-code-aggressive
repro.cc:22:10: warning: 'return' will never be executed [-Wunreachable-code-return]
   22 | return 4;
      |          ^
repro.cc:12:11: warning: code will never be executed [-Wunreachable-code]
   12 | Location::CurrentWithoutFunctionName());
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2 warnings generated.
```

The first diag points at the line that has the problem. That's good.

The second diag doesn't point even close to the problem. If the macro is in a header and the diag is in a file that uses the macro 20+ times, it's very hard to see where the problem is.

</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJycVcuO6jgTfhqzKYESJyGwyCLNRX9LLX7pqKWzRI5dJB45NvIFztmcZx85SUPfRzMWAuyq-uqrm82ck61GrEjxQIrtjAXfGVtpyc2sMeJ3RZbJ9ElqQnPgzIPFszULzklSc8WcgyfDmZdGAykfSFLDOTRKcpLVcQPOMy_5XWkTrEXtf0rfmeD3QfN4fGA9EroaLOLiRjsPvGOW0BpOUuFRsx6BZFs4HpsglZf6uH982kUruiZ0c7OV2oOSGo869A3adzZPj4ebzZpkkTEpt9Ofl5AOxv9AxjsUB2PRB6t31hr7aYT466wkl_4ro49hveSC0CWoW_KybVS7ybKaZPX3yXodQvQwVPFBT85JsSXFdjrkiul2xNSmR9vi12KpY_a-lvujZ1IdOVMKxagW3f_5Jv7PMk1oJvAkNcLh_88_dvXmf7vtqPtdJul6tI5FPk3qU1U-4IyuAEYIyO8cbhDtO4i3ql9BThCvh-PdluZggid032pC942M30MSYc5vEwTzn0HbGChrFM65EThnbWvROXlBktS3UctqSklWpwnJargyq-VQDiC0nIpNS7hKpUDjBS00CPgLefAoYgU_8XPvkaE3KQVSbj6EH1c8vy1S7N7ySgde6Tte0cW_4nMjko5E_uMY3BmTYvfnnxdJavrC20GLGi3zKBYfq_vcIZykdR6EZC2cjdTeAfPgOxxuG_Ad89AxN5ycrWkU9gt47pgntHTQGjPijlgOudFiBBMGXaygH2EBL6iBK-MQvHkL93ga9j3j1oB0IDUw6JAJtMC0GIQD5ossXp0jteDQvTKmCaEP4GWPjtANyJHlBe1v6JgV0bNDhGuHFl9zAOliGDNRZWKdrdkMq7TMk7QoyjSfddWaiVPZLIVI1mvesFVeYlmcWJIsy4w3KZ_Jiia0SChN02VWpPkiZw0XKE5LIVZZ3ixJnmDPpFoodekXxrYz6VzAKqWrdF3MFGtQueHJolTjFQYpoTS-YLaKRvMmtI7kiZLOuzuMl15hFdPj4Dr2EgQXexCcCZbj_TZmJx9fDpqltMyy1SxYVXXen11sSLqPgy19F5oFNz2h--hi-pmfrfkLeZz9gZgjdD8xv1T07wAAAP__aaNQkw">