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diff --git a/gn/tools/gn/label_ptr.h b/gn/tools/gn/label_ptr.h
new file mode 100644
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+++ b/gn/tools/gn/label_ptr.h
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+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef TOOLS_GN_LABEL_PTR_H_
+#define TOOLS_GN_LABEL_PTR_H_
+
+#include <stddef.h>
+
+#include <functional>
+
+#include "tools/gn/label.h"
+
+class Config;
+class ParseNode;
+class Target;
+
+// Structure that holds a labeled "thing". This is used for various places
+// where we need to store lists of targets or configs. We sometimes populate
+// the pointers on another thread from where we compute the labels, so this
+// structure lets us save them separately. This also allows us to store the
+// location of the thing that added this dependency.
+template <typename T>
+struct LabelPtrPair {
+  typedef T DestType;
+
+  LabelPtrPair() : label(), ptr(nullptr), origin(nullptr) {}
+
+  explicit LabelPtrPair(const Label& l)
+      : label(l), ptr(nullptr), origin(nullptr) {}
+
+  // This contructor is typically used in unit tests, it extracts the label
+  // automatically from a given pointer.
+  explicit LabelPtrPair(const T* p)
+      : label(p->label()), ptr(p), origin(nullptr) {}
+
+  ~LabelPtrPair() {}
+
+  Label label;
+  const T* ptr;  // May be NULL.
+
+  // The origin of this dependency. This will be null for internally generated
+  // dependencies. This happens when a group is automatically expanded and that
+  // group's members are added to the target that depends on that group.
+  const ParseNode* origin;
+};
+
+typedef LabelPtrPair<Config> LabelConfigPair;
+typedef LabelPtrPair<Target> LabelTargetPair;
+
+typedef std::vector<LabelConfigPair> LabelConfigVector;
+typedef std::vector<LabelTargetPair> LabelTargetVector;
+
+// Comparison and search functions ---------------------------------------------
+
+// To do a brute-force search by label:
+// std::find_if(vect.begin(), vect.end(), LabelPtrLabelEquals<Config>(label));
+template <typename T>
+struct LabelPtrLabelEquals {
+  explicit LabelPtrLabelEquals(const Label& l) : label(l) {}
+
+  bool operator()(const LabelPtrPair<T>& arg) const {
+    return arg.label == label;
+  }
+
+  const Label& label;
+};
+
+// To do a brute-force search by object pointer:
+// std::find_if(vect.begin(), vect.end(), LabelPtrPtrEquals<Config>(config));
+template <typename T>
+struct LabelPtrPtrEquals {
+  explicit LabelPtrPtrEquals(const T* p) : ptr(p) {}
+
+  bool operator()(const LabelPtrPair<T>& arg) const { return arg.ptr == ptr; }
+
+  const T* ptr;
+};
+
+// To sort by label:
+// std::sort(vect.begin(), vect.end(), LabelPtrLabelLess<Config>());
+template <typename T>
+struct LabelPtrLabelLess {
+  bool operator()(const LabelPtrPair<T>& a, const LabelPtrPair<T>& b) const {
+    return a.label < b.label;
+  }
+};
+
+// Default comparison operators -----------------------------------------------
+//
+// The default hash and comparison operators operate on the label, which should
+// always be valid, whereas the pointer is sometimes null.
+
+template <typename T>
+inline bool operator==(const LabelPtrPair<T>& a, const LabelPtrPair<T>& b) {
+  return a.label == b.label;
+}
+
+template <typename T>
+inline bool operator<(const LabelPtrPair<T>& a, const LabelPtrPair<T>& b) {
+  return a.label < b.label;
+}
+
+namespace std {
+
+template <typename T>
+struct hash<LabelPtrPair<T>> {
+  std::size_t operator()(const LabelPtrPair<T>& v) const {
+    hash<Label> h;
+    return h(v.label);
+  }
+};
+
+}  // namespace std
+
+#endif  // TOOLS_GN_LABEL_PTR_H_