diff --git a/lib/System/Win32/Win32.h b/lib/System/Win32/Win32.h
index fb2c7e96fdf..ab6b3c2b498 100644
--- a/lib/System/Win32/Win32.h
+++ b/lib/System/Win32/Win32.h
@@ -31,3 +31,6 @@ inline void ThrowError(const std::string& msg) {
   throw s;
 }
 
+inline void ThrowErrno(const std::string& prefix) {
+    ThrowError(prefix + ": " + strerror(errno));
+}