Dont' use O_CLOEXEC on Windows, since it doesn't exist.

llvm-svn: 228590
diff --git a/lldb/source/Utility/PseudoTerminal.cpp b/lldb/source/Utility/PseudoTerminal.cpp
index 55d4a9a..e728d4a 100644
--- a/lldb/source/Utility/PseudoTerminal.cpp
+++ b/lldb/source/Utility/PseudoTerminal.cpp
@@ -239,7 +239,11 @@
         error_str[0] = '\0';
 
     pid_t pid = LLDB_INVALID_PROCESS_ID;
-    if (OpenFirstAvailableMaster (O_RDWR | O_CLOEXEC, error_str, error_len))
+    int flags = O_RDWR;
+#if !defined(_MSC_VER)
+    flags |= O_CLOEXEC;
+#endif
+    if (OpenFirstAvailableMaster (flags, error_str, error_len))
     {
         // Successfully opened our master pseudo terminal