Bug#888220: ignition-math4: FTBFS on mips(el) and hppa: UNIT_Helpers_TEST fails badly

Source: ignition-math4
Version: 4.0.0+dfsg1-1
Severity: important
Tags: upstream
Justification: fails to build from source
User: [email protected]
Usertags: mips mipsel

Builds of ignition-math4 for mips, mipsel, and the non-release
architecture hppa have been failing as detailed at

https://buildd.debian.org/status/fetch.php?pkg=ignition-math4&arch=mips&ver=4.0.0%2Bdfsg1-1&stamp=1516376024&raw=0
https://buildd.debian.org/status/fetch.php?pkg=ignition-math4&arch=mipsel&ver=4.0.0%2Bdfsg1-1&stamp=1516373688&raw=0
https://buildd.debian.org/status/fetch.php?pkg=ignition-math4&arch=hppa&ver=4.0.0%2Bdfsg1-1&stamp=1516373442&raw=0

On mips, this test manages to make ctest itself to run out of memory:

        Start 11: UNIT_Helpers_TEST
  terminate called after throwing an instance of 'std::bad_alloc'
    what():  std::bad_alloc
  Makefile:143: recipe for target 'test' failed
  make[2]: *** [test] Aborted

On mipsel and hppa, HelpersTest.Pair spews millions(!) of errors and
then hits a timeout:

  11/75 Test #11: UNIT_Helpers_TEST ......................***Timeout 240.12 sec
  [...]
  [ RUN      ] HelpersTest.Pair
  /<<BUILDDIR>>/ignition-math4-4.0.0+dfsg1/src/Helpers_TEST.cc:516: Failure
        Expected: a
        Which is: 4294962295
  To be equal to: c
        Which is: 4294962296
  [...]
  /<<BUILDDIR>>/ignition-math4-4.0.0+dfsg1/src/Helpers_TEST.cc:516: Failure
        Expected: a
        Which is: 4294963544
  To be equal to: c
        Which is: 4294963545
  
        Start 12: check_UNIT_Helpers_TEST

(above output from mipsel, hppa is similar)

NB: the mipsel and hppa logs are a couple hundred megs apiece, so you
may wish to consider taking it easy on your browser by downloading raw
logs and viewing them with less. ;-)

Could you please take a look?

Thanks!