2016-05-19 17:29:46 +08:00
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.. title:: clang-tidy - misc-incorrect-roundings
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2016-02-08 18:16:13 +08:00
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misc-incorrect-roundings
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Checks the usage of patterns known to produce incorrect rounding.
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2016-02-08 23:09:34 +08:00
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Programmers often use::
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(int)(double_expression + 0.5)
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2016-02-08 18:16:13 +08:00
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to round the double expression to an integer. The problem with this:
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1. It is unnecessarily slow.
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2. It is incorrect. The number 0.499999975 (smallest representable float
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number below 0.5) rounds to 1.0. Even worse behavior for negative
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numbers where both -0.5f and -1.4f both round to 0.0.
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