<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/87446>87446</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Clang stack frame is too large in specific scenarios.
        </td>
    </tr>

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

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

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

<pre>
    test.c
```
#define PERROR(fmt)                  \
  do {                               \
    char dbg_buffer[4096 +1]={0};    \
  } while(0);

void foo() {
  PERROR("/opt/1");
  PERROR("/opt/2");
  PERROR("/opt/3");
}
```
clang
```
% clang test.c -o test.s -S -O0
foo:                                    // @foo
        stp     x29, x30, [sp, #-32]!           // 16-byte Folded Spill
        str     x28, [sp, #16]                  // 8-byte Folded Spill
        mov     x29, sp
        sub     sp, sp, #3, lsl #12             // =12288
  ...
```
gcc
```
% gcc test.c -o test.s -S -O0
foo:
        mov     x12, 4128
        sub     sp, sp, x12
  ...
```
https://godbolt.org/z/od5Yc1zKr
clang is 12288，while gcc is only 4128. It seems that  clang is (PERROR nums * struct size), and gcc is more reasonable.
</pre>
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