[llvm] Fix _WIN32 Wundef warning; NFC (PR #159301)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-support

Author: Sven van Haastregt (svenvh)

<details>
<summary>Changes</summary>

The `_WIN32` macro is tested for defined-ness everywhere else.  The instance here triggers a warning when compiling with `-Wundef`.

---
Full diff: https://github.com/llvm/llvm-project/pull/159301.diff


1 Files Affected:

- (modified) llvm/lib/Support/raw_socket_stream.cpp (+1-1) 


``````````diff
diff --git a/llvm/lib/Support/raw_socket_stream.cpp b/llvm/lib/Support/raw_socket_stream.cpp
index fd1c681672138..3b510d357fd5d 100644
--- a/llvm/lib/Support/raw_socket_stream.cpp
+++ b/llvm/lib/Support/raw_socket_stream.cpp
@@ -255,7 +255,7 @@ manageTimeout(const std::chrono::milliseconds &Timeout,
   // has been canceled by another thread
   if (getActiveFD() == -1 || (CancelFD.has_value() && FD[1].revents & POLLIN))
     return std::make_error_code(std::errc::operation_canceled);
-#if _WIN32
+#ifdef _WIN32
   if (PollStatus == SOCKET_ERROR)
 #else
   if (PollStatus == -1)

``````````

</details>


https://github.com/llvm/llvm-project/pull/159301