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diff --git a/absl/log/die_if_null.h b/absl/log/die_if_null.h
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+// Copyright 2022 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: log/die_if_null.h
+// -----------------------------------------------------------------------------
+//
+// This header declares macro `ABSL_DIE_IF_NULL`.
+
+#ifndef ABSL_LOG_DIE_IF_NULL_H_
+#define ABSL_LOG_DIE_IF_NULL_H_
+
+#include <stdint.h>
+
+#include <utility>
+
+#include "absl/base/attributes.h"
+#include "absl/base/config.h"
+#include "absl/base/optimization.h"
+
+// ABSL_DIE_IF_NULL()
+//
+// `ABSL_DIE_IF_NULL` behaves as `CHECK_NE` against `nullptr` but *also*
+// "returns" its argument.  It is useful in initializers where statements (like
+// `CHECK_NE`) can't be used.  Outside initializers, prefer `CHECK` or
+// `CHECK_NE`. `ABSL_DIE_IF_NULL` works for both raw pointers and (compatible)
+// smart pointers including `std::unique_ptr` and `std::shared_ptr`; more
+// generally, it works for any type that can be compared to nullptr_t.  For
+// types that aren't raw pointers, `ABSL_DIE_IF_NULL` returns a reference to
+// its argument, preserving the value category. Example:
+//
+//   Foo() : bar_(ABSL_DIE_IF_NULL(MethodReturningUniquePtr())) {}
+//
+// Use `CHECK(ptr)` or `CHECK(ptr != nullptr)` if the returned pointer is
+// unused.
+#define ABSL_DIE_IF_NULL(val) \
+  ::absl::log_internal::DieIfNull(__FILE__, __LINE__, #val, (val))
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace log_internal {
+
+// Crashes the process after logging `exprtext` annotated at the `file` and
+// `line` location. Called when `ABSL_DIE_IF_NULL` fails. Calling this function
+// generates less code than its implementation would if inlined, for a slight
+// code size reduction each time `ABSL_DIE_IF_NULL` is called.
+ABSL_ATTRIBUTE_NORETURN ABSL_ATTRIBUTE_NOINLINE void DieBecauseNull(
+    const char* file, int line, const char* exprtext);
+
+// Helper for `ABSL_DIE_IF_NULL`.
+template <typename T>
+ABSL_MUST_USE_RESULT T DieIfNull(const char* file, int line,
+                                 const char* exprtext, T&& t) {
+  if (ABSL_PREDICT_FALSE(t == nullptr)) {
+    // Call a non-inline helper function for a small code size improvement.
+    DieBecauseNull(file, line, exprtext);
+  }
+  return std::forward<T>(t);
+}
+
+}  // namespace log_internal
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_LOG_DIE_IF_NULL_H_