Matrix construction over prime field fails for some types of inputs

[vneiger]

Steps To Reproduce

The constructor for matrices of type matrix_modn_dense is supposed to accept a matrix of Python integers int. Yet it will fail with overflow if given integers that exceed the maximum value for a long.

Try the following example:

sage: x = int(2**128 + 1)
sage: mat = matrix(GF(9001), [[x]])

Expected Behavior

We expect that mat is constructed as an 1 x 1 matrix with single entry the element GF(9001)(x) (represented by 7633 in sage).

Actual Behavior

[...]
File src/sage/matrix/matrix_modn_dense_template.pxi:531, in sage.matrix.matrix_modn_dense_double.Matrix_modn_dense_template.__init__()
    529 x = next(it)
    530 if type(x) is int:
--> 531     tmp = (<long>x) % p
    532     v[j] = tmp + (tmp<0)*p
    533 elif type(x) is IntegerMod_int and (<IntegerMod_int>x)._parent is R:

OverflowError: Python int too large to convert to C long

Additional Information

We see in the error message that there is an attempt to convert x into a long, hence the overflow error.

Environment

- **OS**: ubuntu 22.04
- **Sage Version**: 10.1.rc0

Checklist

• I have searched the existing issues for a bug report that matches the one I want to file, without success.
• I have read the documentation and troubleshoot guide