Fix invalid use of sig_on() in sage.matrix.matrix_sparse.Matrix_sparse._multiply_classical

[jdemeyer]

sage -t --long src/sage/rings/number_field/number_field.py
**********************************************************************
File "src/sage/rings/number_field/number_field.py", line 1288, in sage.rings.number_field.number_field.NumberField_generic
Failed example:
    for chi in G:
        D = ModularSymbols(chi, 2, -1).cuspidal_subspace().new_subspace().decomposition()
        for f in D:
            elt = f.q_eigenform(10, 'alpha')[3]
            assert elt.is_integral()
Exception raised:
    Traceback (most recent call last):
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 671, in _run
        self.compile_and_execute(example, compiler, test.globs)
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 1095, in compile_and_execute
        exec(compiled, globs)
      File "<doctest sage.rings.number_field.number_field.NumberField_generic[47]>", line 4, in <module>
        elt = f.q_eigenform(Integer(10), 'alpha')[Integer(3)]
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/modular/modsym/space.py", line 1263, in q_eigenform
        ext = [self.eigenvalue(n, names) for n in range(f.prec(),prec)]
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/modular/hecke/module.py", line 1304, in eigenvalue
        Tn_e = self._eigen_nonzero_element(n)
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/modular/hecke/module.py", line 635, in _eigen_nonzero_element
        return A._hecke_image_of_ith_basis_vector(n, i)
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/modular/hecke/module.py", line 650, in _hecke_image_of_ith_basis_vector
        return T.apply_sparse(self.gen(i))
      File "/home/vdelecro/sage_patchbot/local/lib/python2.7/site-packages/sage/modular/modsym/hecke_operator.py", line 72, in apply_sparse
        return M(v.parent()((W * R).row(0)))
      File "sage/structure/element.pyx", line 3681, in sage.structure.element.Matrix.__mul__ (build/cythonized/sage/structure/element.c:22564)
        return coercion_model.bin_op(left, right, mul)
      File "sage/structure/coerce.pyx", line 1158, in sage.structure.coerce.CoercionModel.bin_op (build/cythonized/sage/structure/coerce.c:9985)
        return (<Action>action)._act_(x, y)
      File "sage/matrix/action.pyx", line 260, in sage.matrix.action.MatrixMatrixAction._act_ (build/cythonized/sage/matrix/action.c:4606)
        prod = A._matrix_times_matrix_(B)
      File "sage/matrix/matrix0.pyx", line 5213, in sage.matrix.matrix0.Matrix._matrix_times_matrix_ (build/cythonized/sage/matrix/matrix0.c:35087)
        return self._multiply_classical(right)
      File "sage/matrix/matrix_sparse.pyx", line 193, in sage.matrix.matrix_sparse.Matrix_sparse._multiply_classical (build/cythonized/sage/matrix/matrix_sparse.c:3861)
        sig_on()
    SystemError: calling remove_from_pari_stack() inside sig_on()
**********************************************************************

Component: cython

Author: Jeroen Demeyer

Branch/Commit: c9b0cc9

Reviewer: Frédéric Chapoton

Issue created by migration from https://trac.sagemath.org/ticket/27477

[jdemeyer]

Branch: u/jdemeyer/fix_invalid_use_of_sig_on___in_sage_matrix_matrix_sparse_matrix_sparse__multiply_classical

[jdemeyer]

New commits:

c9b0cc9

Fix invalid uses of sig_on() in sage.matrix.matrix_sparse.Matrix_sparse

[jdemeyer]

Commit: c9b0cc9

[jdemeyer]

Author: Jeroen Demeyer

[fchapoton]

Reviewer: Frédéric Chapoton

[fchapoton]

comment:3

ok, thx

[embray]

comment:4

Ticket retargeted after milestone closed (if you don't believe this ticket is appropriate for the Sage 8.8 release please retarget manually)

[vbraun]

Changed branch from u/jdemeyer/fix_invalid_use_of_sig_on___in_sage_matrix_matrix_sparse_matrix_sparse__multiply_classical to c9b0cc9