GC-related unable to make sense of Maxima expression '(kill(sage4)$o44)...'

[vbraun]

File "src/sage/tests/books/computational-mathematics-with-sagemath/graphique_doctest.py", line 112, in sage.tests.books.computational-mathematics-with-sagemath.graphique_doctest
Failed example:
    for i in srange(-2, 2, 0.2):  # long time
        g += line(desolve_rk4(DE, y(x), ics=[1, i],\
                          step=0.05, end_points=[0,2]))
        g += line(desolve_rk4(DE, y(x), ics=[-1, i],\
                          step=0.05, end_points=[-2,0]))
Exception raised:
    Traceback (most recent call last):
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 671, in _run
        self.compile_and_execute(example, compiler, test.globs)
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 1095, in compile_and_execute
        exec(compiled, globs)
      File "<doctest sage.tests.books.computational-mathematics-with-sagemath.graphique_doctest[50]>", line 3, in <module>
        step=RealNumber('0.05'), end_points=[Integer(0),Integer(2)]))
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/calculus/desolvers.py", line 1378, in desolve_rk4
        sol_2=maxima(cmd).sage()
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/interfaces/interface.py", line 1074, in sage
        return self._sage_(*args, **kwds)
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/interfaces/maxima_abstract.py", line 1238, in _sage_
        maxima=self.parent())
      File "/home/buildbot/slave/sage_git/build/local/lib/python2.7/site-packages/sage/calculus/calculus.py", line 2163, in symbolic_expression_from_maxima_string
        raise TypeError("unable to make sense of Maxima expression '%s' in Sage"%s)
    TypeError: unable to make sense of Maxima expression '(kill(sage4)$o44)[[1.0,-2.0],[1.05,-2.149874965475482],[1.1,-2.298999939830521],[1.15,-2.446624921487998],[1.2,-2.591999909207452],[1.25,-2.7343749020044],[1.3,-2.872999899091065],[1.35,-3.007124899832311],[1.4,-3.135999903712506],[1.45,-3.258874910310362],[1.5,-3.374999919279643],[1.55,-3.483624930334245],[1.6,-3.58399994323656],[1.65,-3.675374957788335],[1.7,-3.756999973823437],[1.75,-3.828124991202094],[1.8,-3.888000009806273],[1.85,-3.935875029535953],[1.9,-3.971000050306113],[1.95,-3.992625072044261],[2.0,-4.000000094688424]]' in Sage
**********************************************************************
1 item had failures:
   1 of 117 in sage.tests.books.computational-mathematics-with-sagemath.graphique_doctest
    [116 tests, 1 failure, 42.43 s]
----------------------------------------------------------------------
sage -t --long src/sage/tests/books/computational-mathematics-with-sagemath/graphique_doctest.py  # 1 doctest failed
----------------------------------------------------------------------

CC: @antonio-rojas

Component: packages: standard

Keywords: random_fail, sdl

Issue created by migration from https://trac.sagemath.org/ticket/27250

[jdemeyer]

comment:1

Again, not random but GC-related.

[vbraun]

comment:2

Looks more like not keeping stdio/stderr/ptty echo separated properly. Possibly related: #26625

[edd8e884-f507-429a-b577-5d554626c0fe]

comment:3

For what is worth, i can reproduce the error on my 32bit patchbot, see the log https://patchbot.sagemath.org/log/0/debian/9.7/i686/4.9.0-7-686/tmonteil-debian-stretch-32/2019-03-20%2016:16:33

[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)

[edd8e884-f507-429a-b577-5d554626c0fe]

comment:5

For information, the problem is still there on 8.8.beta2 : https://patchbot.sagemath.org/log/0/debian/9.7/i686/4.9.0-7-686/tmonteil-debian-stretch-32/2019-04-17%2019:25:29 but apparently, other (non-32-bit) patchbots do not see this issue https://patchbot.sagemath.org/ticket/0/

[jdemeyer]

Description changed:

--- 
+++ 
@@ -1,4 +1,3 @@
-This seems to be exercised by #23572 but obviously isn't caused by it:

File "src/sage/tests/books/computational-mathematics-with-sagemath/graphique_doctest.py", line 112, in sage.tests.books.computational-mathematics-with-sagemath.graphique_doctest

[embray]

comment:7

As the Sage-8.8 release milestone is pending, we should delete the sage-8.8 milestone for tickets that are not actively being worked on or that still require significant work to move forward. If you feel that this ticket should be included in the next Sage release at the soonest please set its milestone to the next release milestone (sage-8.9).

[edd8e884-f507-429a-b577-5d554626c0fe]

Changed keywords from random_fail to random_fail, sdl