<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/115149>115149</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Miscompile with -O3 and -O0/1/2 since 18.1.0
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          cardigan1008
      </td>
    </tr>
</table>

<pre>
    When I compiled this code with -O0/1/2, its output is 0. However, with -O3, it returned 143:

```c
int printf(const char *, ...);
char a, b;
int c;
char *e = &b;
int f(char *g, int *k) {
  char *d = g + *k;
  for (; *d && *d <= ' '; d++)
    ;
  if (*d)
    return 0;
  return 1;
}
int l(int g) {
  char h[] = {a, a, a};
  int i[] = {g};
  int j = f(h, i);
  return j;
}
long m() {
  *e = 255;
  for (; l(b + 1);)
    return 0;
  for (;;)
 ;
}
int main() {
  m();
  printf("%d\n", c);
}
```

Details can be found here: https://godbolt.org/z/MKW3535W6
</pre>
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