Warn when number base conversion loses precision#22371
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_php_math_basetozval is used for base_convert, bindec, hexdec and octdec. It uses an integer or double for the internal representation of the number. When the input number is too large to fit in there, it loses precision. This commit emits a notice when this happens. Discussion thread: https://news-web.php.net/php.internals/131364
The test for overflow used a large integer, larger than PHP_INT_MAX. Previously it used base_convert to create an integer 4 * PHP_INT_MAX, but that now raises an overflow warning. We now use PHP_INT_MAX and append a zero, giving 10 * PHP_INT_MAX. We can't just use 4 * PHP_INT_MAX, because that is converted to a float and represented as 3.6893488147419E+19 instead of 36893488147419104082.
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_php_math_basetozval is used for base_convert, bindec, hexdec and octdec. It uses an integer or double for the internal representation of the number. When the input number is too large to fit in there, it loses precision. This commit emits a notice when this happens.
Discussion thread: https://news-web.php.net/php.internals/131364