<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/68782>68782</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] character '$' cannot be specified by a universal character name
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    `clang test.c -std=c99 -fdollars-in-identifiers`

```
void abort (void);
int a$b(void) { return 1; }
int main (void)
{
  if (a\u0024b() != 1)
    abort ();

  return 0;
}
```

error:
```
<source>:8:8: error: character '$' cannot be specified by a universal character name
    8 |   if (a\u0024b() != 1)
      |        ^
<source>:8:7: error: use of undeclared identifier 'a'
    8 |   if (a\u0024b() != 1)
      | ^
<source>:8:8: error: expected ')'
    8 |   if (a\u0024b() != 1)
 |        ^
<source>:8:6: note: to match this '('
    8 |   if (a\u0024b() != 1)
      |      ^
3 errors generated.
Compiler returned: 1
```

while llvm-16 can compile this code successfully.

url: https://godbolt.org/z/aPYE5KE77

</pre>
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