<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/103495>103495</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [AArch64][ARM] Why fpack-struct=4 has a higher priority than attribute
        </td>
    </tr>

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

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

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

<pre>
    ```
struct s1
{
  int __attribute__ ((aligned (8))) a;
};

struct
{
  char c;
  struct s1 m;
} v;

int
main (void)
{
  if ((int)&v.m & 7)
    abort ();
  exit (0);
}
```
compile with only one option：-fpack-struct=4

gcc could pass this testcase, but clang could not.
https://godbolt.org/z/h5T5rdYWb

The code can be simplified as follows:
```
struct s1
{
  int __attribute__ ((aligned (8))) a;
}s;
```
https://godbolt.org/z/EbGsEz6eP

if compile without -fpack-struct=4, the alignment  of struct is 8, as same as attribue. But if compile with -fpack-struct=4, the alignment  of struct is 4. Why fpack-struct=4 has a higher priority than attribute? I think attribute should has a higher priority than Compilation options




</pre>
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