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This noncompliant code example leads to to undefined behavior if 16 if the integral part of f_a cannot be represented as an integer:
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As a result of these conversions, it is possible that d_a is outside the range of values that can be represented by a float or that big_d is outside the range of values that can be represented as either a float or a double. If this is the case, the result is is undefined on behavior 17 on implementations that do not support Annex F, "IEC 60559 Floating-Point Arithmetic."
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