chromium/third_party/breakpad/breakpad/src/common/safe_math.h

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// safe_math.h: Helpful math functions.
#ifndef SAFE_MATH_H__
#define SAFE_MATH_H__

#include <utility>

namespace google_breakpad {

// Adds `a` and `b`, returning a pair of:
// - The result after any truncation.
// - Whether an overflow/underflow occurred.
template <typename T>
std::pair<T, bool> AddWithOverflowCheck(T a, T b) { … }

template <typename T>
T AddIgnoringOverflow(T a, T b) { … }

}  // namespace google_breakpad

#endif  // SAFE_MATH_H__