<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54086>54086</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang in Cygwin: -o /dev/stdout may confuse output redirection
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          pmor13
      </td>
    </tr>
</table>

<pre>
    Scenario:
```
$ clang t455.c -S -o /dev/stdout
        .text
        <asm code>

# introduce the error

$ clang t455.c -S -o /dev/stdout
t455.c:26:1: error: unknown type name 'x'
x
^
t455.c:26:2: error: expected identifier or '('
x
 ^
2 errors generated.

# fix the error

$ clang t455.c -S -o /dev/stdout
# nothing is printed

$ clang --version
clang version 8.0.1 (tags/RELEASE_801/final)
```
Why `clang t455.c -S -o /dev/stdout` leads to nothing is printed?

Note: GCC on Cygwin does not have this issue.
</pre>
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