diff --git a/lib/Support/Windows/Process.inc b/lib/Support/Windows/Process.inc
index 8d646b3217a..18aef610d54 100644
--- a/lib/Support/Windows/Process.inc
+++ b/lib/Support/Windows/Process.inc
@@ -47,7 +47,6 @@
 #endif
 
 using namespace llvm;
-using namespace sys;
 
 // This function retrieves the page size using GetNativeSystemInfo() and is
 // present solely so it can be called once to initialize the self_process member