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diff --git a/src/compat/assumptions.h b/src/compat/assumptions.h
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+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+// Compile-time verification of assumptions we make.
+
+#ifndef BITCOIN_COMPAT_ASSUMPTIONS_H
+#define BITCOIN_COMPAT_ASSUMPTIONS_H
+
+#include <limits>
+
+// Assumption: We assume that the macro NDEBUG is not defined.
+// Example(s): We use assert(...) extensively with the assumption of it never
+//             being a noop at runtime.
+#if defined(NDEBUG)
+# error "Bitcoin cannot be compiled without assertions."
+#endif
+
+// Assumption: We assume a C++11 (ISO/IEC 14882:2011) compiler (minimum requirement).
+// Example(s): We assume the presence of C++11 features everywhere :-)
+// Note:       MSVC does not report the expected __cplusplus value due to legacy
+//             reasons.
+#if !defined(_MSC_VER)
+// ISO Standard C++11 [cpp.predefined]p1:
+// "The name __cplusplus is defined to the value 201103L when compiling a C++
+//  translation unit."
+static_assert(__cplusplus >= 201103L, "C++11 standard assumed");
+#endif
+
+// Assumption: We assume the floating-point types to fulfill the requirements of
+//             IEC 559 (IEEE 754) standard.
+// Example(s): Floating-point division by zero in ConnectBlock, CreateTransaction
+//             and EstimateMedianVal.
+static_assert(std::numeric_limits<float>::is_iec559, "IEEE 754 float assumed");
+static_assert(std::numeric_limits<double>::is_iec559, "IEEE 754 double assumed");
+
+// Assumption: We assume eight bits per byte (obviously, but remember: don't
+//             trust -- verify!).
+// Example(s): Everywhere :-)
+static_assert(std::numeric_limits<unsigned char>::digits == 8, "8-bit byte assumed");
+
+// Assumption: We assume floating-point widths.
+// Example(s): Type punning in serialization code (ser_{float,double}_to_uint{32,64}).
+static_assert(sizeof(float) == 4, "32-bit float assumed");
+static_assert(sizeof(double) == 8, "64-bit double assumed");
+
+// Assumption: We assume integer widths.
+// Example(s): GetSizeOfCompactSize and WriteCompactSize in the serialization
+//             code.
+static_assert(sizeof(short) == 2, "16-bit short assumed");
+static_assert(sizeof(int) == 4, "32-bit int assumed");
+
+// Assumption: We assume size_t to be 32-bit or 64-bit.
+// Example(s): size_t assumed to be at least 32-bit in ecdsa_signature_parse_der_lax(...).
+//             size_t assumed to be 32-bit or 64-bit in MallocUsage(...).
+static_assert(sizeof(size_t) == 4 || sizeof(size_t) == 8, "size_t assumed to be 32-bit or 64-bit");
+static_assert(sizeof(size_t) == sizeof(void*), "Sizes of size_t and void* assumed to be equal");
+
+// Some important things we are NOT assuming (non-exhaustive list):
+// * We are NOT assuming a specific value for std::endian::native.
+// * We are NOT assuming a specific value for std::locale("").name().
+// * We are NOT assuming a specific value for std::numeric_limits<char>::is_signed.
+
+#endif // BITCOIN_COMPAT_ASSUMPTIONS_H