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.
Description: fix python integer type checks in polynomial_integer_dense_flint.pyx
python 3 changes the standard integer types, in python2 a python "int" was
equivilent to a C "long" and a python "long" was an arbitary precision type.
In python 3 a python "int" is now an arbitary precision type and a python
"long" does not exist any more.
This patch adds additional checks that a python int will fit in the range of
a C long before passing it to routines that require it to fit in one. It also
locally defines long=int on python 3 so that isinstance(x0,long) will correctly
test for an arbitary precision python integer.
Author: Peter Michael Green
---
The information above should follow the Patch Tagging Guidelines, please
checkout http://dep.debian.net/deps/dep3/ to learn about the format. Here
are templates for supplementary fields that you might want to add:
Origin: ,
Bug:
Bug-Debian: https://bugs.debian.org/
Bug-Ubuntu: https://launchpad.net/bugs/
Forwarded:
Reviewed-By:
Last-Update: 2019-11-28
--- sagemath-8.9.orig/sage/src/sage/rings/polynomial/polynomial_integer_dense_flint.pyx
+++ sagemath-8.9/sage/src/sage/rings/polynomial/polynomial_integer_dense_flint.pyx
@@ -36,12 +36,21 @@ from __future__ import absolute_import,
from cysignals.memory cimport sig_free
from cysignals.signals cimport sig_on, sig_off
+from libc.limits cimport LONG_MIN
+from libc.limits cimport LONG_MAX
+
include "sage/libs/ntl/decl.pxi"
from cpython.int cimport PyInt_AS_LONG
from sage.libs.gmp.mpz cimport *
from sage.arith.long cimport pyobject_to_long
+import sys
+#we use this later in an isinstance test to detect a python arbitary precision
+#integer
+if sys.version_info.major > 3:
+long = int
+
from sage.rings.polynomial.polynomial_element cimport Polynomial
from sage.structure.element cimport ModuleElement, Element
from sage.structure.element import coerce_binop
@@ -241,7 +250,7 @@ cdef class Polynomial_integer_dense_flin
# now fill them in
for ii, a in x:
i = ii[0] if type(ii) is tuple else ii
-if type(a) is int:
+if (type(a) is int) and (LONG_MIN <= a <= LONG_MAX):
sig_on()
fmpz_poly_set_coeff_si(self.__poly, i, a)
sig_off()
@@ -279,7 +288,7 @@ cdef class Polynomial_integer_dense_flin
sig_off()
for i from 0 <= i < len(x):
a = x[i]
-if type(a) is int:
+if (type(a) is int) && (LONG_MIN <= a <= LONG_MAX):
sig_on()
fmpz_poly_set_coeff_si(self.__poly, i, a)
sig_off()
@@ -398,7 +407,7 @@ cdef class Polynomial_integer_dense_flin
( x0).__poly)
sig_off()
return f
-if isinstance(x0, int):
+if isinstance(x0, int) and (LONG_MIN <= x0 <= LONG_MAX):
z = Integer.__new__(Integer)
sig_on()
fmpz_init(a_fmpz)
@@ -1287,7 +1296,7 @@ cdef class Polynomial_integer_dense_flin
"""
if n < 0:
raise IndexError("n must be >= 0")
-if isinstance(value, int):
+if isinstance(value, int) and (LONG_MIN <= value <= LONG_MAX):
sig_on()
fmpz_poly_set_coeff_si(self.__poly, n, value)
sig_off()
