<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/62834>62834</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang crashes on pointer qualified by __seg_gs when optimization is enabled
        </td>
    </tr>

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

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

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

<pre>
    When attempting to compile the provided code using clang-17, the compiler crashes:

Code:
```
void f1(char __seg_gs *s, int n) {
  for (int i = 0; i < n; ++i) s[i] = 0;
}
```

Crash message (also crash on -O2, -O3, -Os)
```
-> $ clang -O2 small.c
fatal error: error in backend: cannot lower memory intrinsic in address space 256
clang: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 17.0.0 (git@github.com:llvm/llvm-project 806dea46be4c49dc587b98dab5e4d9d242a6abdb)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/wierton/disk/llvm-project-trunk-compile/bin
clang: note: diagnostic msg:
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: /tmp/small-af9877.c
clang: note: diagnostic msg: /tmp/small-af9877.sh
clang: note: diagnostic msg:

********************
```

My clang version is :
```
-> $ clang -v
clang version 17.0.0 (git@github.com:llvm/llvm-project 806dea46be4c49dc587b98dab5e4d9d242a6abdb)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/wierton/disk/llvm-project-trunk-compile/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/10
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/12
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/9
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/12
Candidate multilib: .;@m64
Selected multilib: .;@m64
```
</pre>
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