1 files changed, 28 insertions, 0 deletions
diff --git a/src/internal/syscall/windows/sysdll/sysdll.go b/src/internal/syscall/windows/sysdll/sysdll.go
new file mode 100644
index 0000000000..4e0018f387
--- /dev/null
+++ b/src/internal/syscall/windows/sysdll/sysdll.go
@@ -0,0 +1,28 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package sysdll is an internal leaf package that records and reports
+// which Windows DLL names are used by Go itself. These DLLs are then
+// only loaded from the System32 directory. See Issue 14959.
+package sysdll
+
+// IsSystemDLL reports whether the named dll key (a base name, like
+// "foo.dll") is a system DLL which should only be loaded from the
+// Windows SYSTEM32 directory.
+//
+// Filenames are case sensitive, but that doesn't matter because
+// the case registered with Add is also the same case used with
+// LoadDLL later.
+//
+// It has no associated mutex and should only be mutated serially
+// (currently: during init), and not concurrent with DLL loading.
+var IsSystemDLL = map[string]bool{}
+
+// Add notes that dll is a system32 DLL which should only be loaded
+// from the Windows SYSTEM32 directory. It returns its argument back,
+// for ease of use in generated code.
+func Add(dll string) string {
+	IsSystemDLL[dll] = true
+	return dll
+}