Bug#887340: gromacs: FTBFS on x32: tests 2 and 13 time out

Source: gromacs
Version: 2018-1
Severity: important
Tags: upstream
Justification: fails to build from source (but built successfully in the past)
User: [email protected]
Usertags: x32

Builds of gromacs 2018 for x32 (admittedly not a release architecture)
have been failing with mysterious timeouts in tests 2 and 13, per
the below excerpts from [1].

Could you please take a look?

Thanks!

[1] https://buildd.debian.org/status/fetch.php?pkg=gromacs&arch=x32&ver=2018-1&stamp=1515722173&raw=0

----------------------------------------------------------------------

 2/24 Test  #2: TestUtilsMpiUnitTests ............***Timeout  30.01 sec
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from MpiSelfTest
[ RUN      ] MpiSelfTest.Runs
[       OK ] MpiSelfTest.Runs (0 ms)
[----------] 1 test from MpiSelfTest (0 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (0 ms total)
[  PASSED  ] 1 test.

[...]

13/24 Test #13: MdrunUtilityMpiUnitTests .........***Timeout  30.01 sec
[==========] Running 13 tests from 2 test cases.
[----------] Global test environment set-up.
[----------] 6 tests from ThreadAffinityMultiRankTest
[...]
[----------] 6 tests from ThreadAffinityMultiRankTest (459 ms total)

[----------] 7 tests from ThreadAffinityHeterogeneousNodesTest
[...]
[----------] 7 tests from ThreadAffinityHeterogeneousNodesTest (776 ms total)

[----------] Global test environment tear-down
[==========] 13 tests from 2 test cases ran. (1236 ms total)
[  PASSED  ] 13 tests.
[...]
92% tests passed, 2 tests failed out of 24

Label Time Summary:
GTest       =  62.39 sec (24 tests)
MpiTest     =  60.02 sec (2 tests)
UnitTest    =  62.39 sec (24 tests)

Total Test time (real) =  62.48 sec

The following tests FAILED:
          2 - TestUtilsMpiUnitTests (Timeout)
         13 - MdrunUtilityMpiUnitTests (Timeout)
Errors while running CTest