Control: forwarded 944648 https://trac.sagemath.org/ticket/28795
On 11/28/19 2:09 AM, peter green wrote: >> All three failures give the error message >> >> OverflowError: Python int too large to convert to C long >> >> from >> >> File "sage/rings/polynomial/polynomial_integer_dense_flint.pyx", line 284, >> in >> sage.rings.polynomial.polynomial_integer_dense_flint.Polynomial_integer_dense_flint.__init__ >> >> (build/cythonized/sage/rings/polynomial/polynomial_integer_dense_flint.cpp:6548) >> fmpz_poly_set_coeff_si(self.__poly, i, a) >> >> Help on finding a fix would be appreciated. > On line 282 of that file (assuming the version at > https://github.com/sagemath/sage/blob/master/src/sage/rings/polynomial/polynomial_integer_dense_flint.pyx > is the same as the one in the Debian package). > > "if type(a) is int:" > > If that conditional is true then the code takes a fast path, which assumes > that the value of "a" fits in a C long. > > In python 2 "int" was a type limited to the size of a c long, so the check > was appropriate. However in python 3 "int" is an arbitrary precision type, so > we need to check if it will fit in the range of a C long. > > There are several other conditionals on types being "int" in the file that > presumably need fixing in the same way. I also spotted a "isinstance(x0, > long):" which i'm pretty sure will fail in python 3 as there is no type long > in python 3. > > I have attached a completely untested patch. > Thanks, that helped a lot. Knowing this I was able to find the upstream ticket were this was fixed only 3 days ago: https://trac.sagemath.org/ticket/28795 I'll apply that upstream patch soon. Sagemath 9.0 will be the first release with Python 3 as default so I hope it will have less problems than 8.9. Best, Tobias
