Other errors in the same build:

0:14:10 load avg: 7.70 [392/420/2] test_http_cookiejar crashed (Exit code -6) -- running: test_buffer (1 min 9 sec), test_pickle (57.5 sec), test_asyncio (3 min 47 sec), test_tarfile (36.8 sec), test_unparse (46.4 sec)
./Include/object.h:492: _Py_NegativeRefcount: Assertion failed: object has negative ref count
Enable tracemalloc to get the memory block allocation traceback

object address  : 0xb53dddc0
object refcount : -1
object type     : 0x772950
object type name: str
object repr     : <refcnt -1 at 0xb53dddc0>

Fatal Python error: _PyObject_AssertFailed: _PyObject_AssertFailed
Python runtime state: initialized

Current thread 0xb6f1b010 (most recent call first):
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/runtest.py", line 193 in runtest
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/runtest_mp.py", line 80 in run_tests_worker
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 654 in _main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 634 in main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 712 in main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/regrtest.py", line 43 in _main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/regrtest.py", line 47 in <module>
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/runpy.py", line 87 in _run_code
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/runpy.py", line 197 in _run_module_as_main

(...)

0:14:26 load avg: 7.84 [402/420/3] test_unicode crashed (Exit code -6) -- running: test_buffer (1 min 25 sec), test_pickle (1 min 13 sec), test_asyncio (4 min 3 sec), test_unparse (1 min 2 sec)
Objects/unicodeobject.c:559: _PyUnicode_CheckConsistency: Assertion failed: compact->wstr_length == ascii->length
Enable tracemalloc to get the memory block allocation traceback

object address  : 0xb12af060
object refcount : 1
object type     : 0x76d950
object type name: str
object repr     : Objects/unicodeobject.c:559: _PyUnicode_CheckConsistency: Assertion failed: compact->wstr_length == ascii->length
Enable tracemalloc to get the memory block allocation traceback

object address  : 0xb12af060
object refcount : 1
object type     : 0x76d950
object type name: str
object repr     : Objects/unicodeobject.c:559: _PyUnicode_CheckConsistency: Assertion failed: compact->wstr_length == ascii->length
Enable tracemalloc to get the memory block allocation traceback

(... same error dozens of times ...)