<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/149749>149749</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            __func__ cannot share addresses with string literals in C
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          Halalaluyafail3
      </td>
    </tr>
</table>

<pre>
    The following program demonstrates this issue:
```c
#include<stdio.h>
int main(){
    static const char X[]="main";
    printf("%i\n",__func__=="main");
 printf("%i\n",X=="main");
}
```
Clang prints 1 then 0 with this program, when it should print 0 then 0.
> The identifier \_\_func\_\_ shall be implicitly declared by the translator as if, immediately following
the opening brace of each function definition, the declaration
> 
> static const char \_\_func\_\_[] = "function-name";
> 
> appeared, where function-name is the name of the lexically-enclosing function.

Section 6.4.2.2 "Predefined identifiers" Paragraph 1 ISO/IEC 9899:2024

Unlike C++, C doesn't say that \_\_func\_\_ can share addresses with string literals so `__func__=="main"` should be zero for the same reason that `X=="main"` is zero.
</pre>
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