Doctest failures on ARM Chromebook

[Bouillaguet]

uname -a
Linux localhost.localdomain 3.4.0 #1 SMP Tue Dec 11 03:10:30 PST 2012 armv7l armv7l armv7l GNU/Linux

cat /proc/cpuinfo
Processor: ARMv7 Processor rev 4 (v7l)
processor: 0
BogoMIPS: 1694.10

processor: 1
BogoMIPS: 1694.10

Features: swp half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt 
CPU implementer: 0x41
CPU architecture: 7
CPU variant: 0x0
CPU part: 0xc0f
CPU revision: 4

Hardware: SAMSUNG EXYNOS5 (Flattened Device Tree)
Revision: 0000
Serial: 0000000000000000

make ptestlong
...
The following tests failed:

sage -t  --long -force_lib devel/sage/sage/rings/arith.py # 1 doctests failed
sage -t  --long -force_lib devel/sage/sage/symbolic/expression.pyx # 1 doctests failed
sage -t  --long -force_lib devel/sage/sage/functions/other.py # 1 doctests failed
----------------------------------------------------------------------
Total time for all tests: 11437.2 seconds

The detailed failures are:

**********************************************************************
File "/home/user/Downloads/sage-5.6/devel/sage/sage/rings/arith.py", line 3162:
    sage: binomial(0.5r, 5)
Expected:
    0.02734375
Got:
    0.02734375000000001
**********************************************************************

**********************************************************************
File "/home/user/Downloads/sage-5.6/devel/sage/sage/symbolic/expression.pyx", line 6698:
    sage: SR(10.0r).gamma()
Expected:
    362880.0
Got:
    362880.00000000047
#0: simplify_sum(expr='sum(q^k,k,0,inf))
#1: simplify_sum(expr=a*'sum(q^k,k,0,inf))
**********************************************************************

and:

**********************************************************************
File "/home/user/Downloads/sage-5.6/devel/sage/sage/functions/other.py", line 664:
    sage: gamma1(float(6))
Expected:
    120.0
Got:
    119.99999999999997
**********************************************************************

[jdemeyer]

Isn't this essentially a duplicate of #10285?

[jpflori]

I guess its the same libc bug isn't it? See ​http://trac.sagemath.org/sage_trac/ticket/10285#comment:36 and ​https://groups.google.com/d/msg/sage-devel/QACdziLhniU/nvBT-EwS4b4J

FYI we have the same problem on Cygwin, see ​http://trac.sagemath.org/sage_trac/ticket/6743#comment:116

[dimpase]

I propose this be closed as a duplicate.