<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/132464>132464</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [MC] Regression regarding .safeseh in inline assembly
        </td>
    </tr>

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

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

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

<pre>
    CC @MaskRay @lhmouse 

There are two closely related regressions in the MC layer, since LLVM 19, regaring using `.safeseh` in inline assembly.

With the following reduced testcase as input:

```c
int foo(void) {
  __asm__(".safeseh my_handler");
 return 0;
}
```

Compiled like this:
```
$ clang -target i686-windows-msvc test.c -g
```

Before e48c4011ca80385573f1b92793c75dc98abb228f ([MC] Cache current fragment in MCStreamer), this runs succesfully. After that commit, it fails, triggering a failed assert:

```
clang: llvm/lib/MC/MCObjectStreamer.cpp:146: MCFragment *llvm::MCObjectStreamer::getCurrentFragment() const: Assertion `CurFrag->getParent() == getCurrentSection().first' failed.
```

If building with asserts disabled, it still succeeds, but closely thereafter, after 626eef5ecf92e98cbfccfa6134e0a760e7592813 ([MC] Optimize getCurrentSectionOnly using CurFrag and make it non-nullable), it also fails in a no-assert build, with the following error:
```
error: all .cv_loc directives for a function must be in the same section
```

</pre>
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