Don't import cysignals.alarm on Windows

src/sage/all.py

@@ -57,6 +57,7 @@
 import os
 import operator
 import math
+import sys
 
 # ############### end setup warnings ###############################
 
@@ -157,7 +158,8 @@
 
 from sage.manifolds.all import *
 
-from cysignals.alarm import alarm, cancel_alarm
+if sys.platform != 'win32':
+    from cysignals.alarm import alarm, cancel_alarm
 
 # Lazily import interacts (#15335)
 lazy_import('sage.interacts', 'all', 'interacts')

src/sage/all__sagemath_objects.py

@@ -21,8 +21,6 @@
 
 from sage.cpython.all import *
 
-from cysignals.alarm import alarm, cancel_alarm
-
 from copy import copy, deepcopy
 
 true = True

src/sage/matrix/benchmark.py

@@ -18,13 +18,17 @@
     ======================================================================
 """
 
-from .constructor import random_matrix, Matrix
+import sys
+
+from sage.matrix.constructor import Matrix, random_matrix
 from sage.misc.lazy_import import lazy_import
+from sage.misc.timing import cputime
+from sage.rings.finite_rings.finite_field_constructor import FiniteField as GF
 from sage.rings.integer_ring import ZZ
 from sage.rings.rational_field import QQ
-from sage.rings.finite_rings.finite_field_constructor import FiniteField as GF
-from sage.misc.timing import cputime
-from cysignals.alarm import AlarmInterrupt, alarm, cancel_alarm
+
+if sys.platform != 'win32':
+    from cysignals.alarm import AlarmInterrupt, alarm, cancel_alarm
 
 lazy_import('sage.interfaces.magma', 'magma')
 

src/sage/parallel/use_fork.py

@@ -13,8 +13,11 @@
 # ****************************************************************************
 
 
+import sys
 from shutil import rmtree
-from cysignals.alarm import AlarmInterrupt, alarm, cancel_alarm
+
+if sys.platform != 'win32':
+    from cysignals.alarm import AlarmInterrupt, alarm, cancel_alarm
 
 from sage.interfaces.process import ContainChildren
 from sage.misc.timing import walltime

src/sage/tests/benchmark.py

@@ -15,29 +15,33 @@
 
     sage: import sage.tests.benchmark
 """
-from cysignals.alarm import alarm, cancel_alarm, AlarmInterrupt
+import sys
+
+if sys.platform != 'win32':
+    from cysignals.alarm import AlarmInterrupt, alarm, cancel_alarm
+
 from sage.combinat.combinat import fibonacci
 from sage.functions.other import factorial
 from sage.interfaces.gp import gp
 from sage.interfaces.macaulay2 import macaulay2
-from sage.interfaces.magma import magma, Magma
+from sage.interfaces.magma import Magma, magma
 from sage.interfaces.maple import maple
 from sage.interfaces.mathematica import mathematica
 from sage.interfaces.maxima import maxima
 from sage.interfaces.singular import singular
-from sage.libs.pari import pari
 from sage.libs.gap.libgap import libgap
+from sage.libs.pari import pari
 from sage.matrix.matrix_space import MatrixSpace
 from sage.misc.functional import log
 from sage.misc.timing import cputime, walltime
 from sage.modular.modsym.modsym import ModularSymbols
 from sage.rings.complex_mpfr import ComplexField
 from sage.rings.finite_rings.finite_field_constructor import GF
 from sage.rings.finite_rings.integer_mod_ring import Integers
-from sage.rings.rational_field import QQ
 from sage.rings.integer import Integer
 from sage.rings.integer_ring import ZZ
 from sage.rings.polynomial.polynomial_ring_constructor import PolynomialRing
+from sage.rings.rational_field import QQ
 from sage.schemes.elliptic_curves.constructor import EllipticCurve