id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
12559,sqrt for cpp_int_backend behaves incorrect for small argument values,Rüdiger Brünner <rbruenner@…>,John Maddock,"The sqrt function for multiprecision integers does not work for small values.
Using this code:
{{{
checked_int128_t int1;
for (int i = 10; i >= 0; i--)
{
	int1 = i;
	try
	{
		int1 = sqrt(int1);
		std::cout << ""sqrt("" << i << "") = "" << int1 << std::endl;
	}
	catch (std::exception& ex)
	{
		std::cout << ""sqrt("" << i << "") -> "" << typeid(ex).name() << "": "" << ex.what() << std::endl;
	}
}
}}}

I get the following output:
{{{
sqrt(10) = 3
sqrt(9) = 3
sqrt(8) = 2
sqrt(7) = 2
sqrt(6) = 2
sqrt(5) = 2
sqrt(4) = 2
sqrt(3) -> class boost::exception_detail::clone_impl<struct boost::exception_detail::error_info_injector<class std::overflow_error> >: Unable to allocate sufficient storage for the value of the result: value overflows the maximum allowable magnitude.
sqrt(2) -> class boost::exception_detail::clone_impl<struct boost::exception_detail::error_info_injector<class std::overflow_error> >: Unable to allocate sufficient storage for the value of the result: value overflows the maximum allowable magnitude.
sqrt(1) = 0
sqrt(0) = 0
}}}

While sqrt(3) and sqrt(2) are raising an exception, sqrt(1) gives a wrong result.",Bugs,closed,To Be Determined,multiprecision,Boost 1.62.0,Problem,fixed,multiprecision integer sqrt,