'svn add' files I forgot for r201224 (Add an option to allow Clang verify

source files for a module only once during)

llvm-svn: 201225

clang/tools/libclang/BuildSystem.cpp

@@ -0,0 +1,22 @@
+//===- BuildSystem.cpp - Utilities for use by build systems ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements various utilities for use by build systems.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang-c/BuildSystem.h"
+#include "llvm/Support/TimeValue.h"
+
+extern "C" {
+unsigned long long clang_getBuildSessionTimestamp(void) {
+  return llvm::sys::TimeValue::now().toEpochTime();
+}
+} // extern "C"
+