Intel compiler support

[joaander]

Original report by me.

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Starting with pull request #211, the intel compiler is no longer supported for building hoomd. This is due to numerous compiler bugs which take significant effort to work around. Additionally, intel compilers are not available for free and thus I do not have one on the Jenkins test server to continually test.

I will accept reasonable pull requests that implement workarounds. However, I will not put in significant effort of my own to support intel - I do not have the time to spare. Here is the status of the testing I have done so far:

• Intel 2015
  • Cannot compile boost::signals in boost 1.61. It seems to work with boost 1.56.
  • Cannot compile pybind11 due to a compiler bug. pybind11 developers refuse to support intel 2015: pybind does not compile with Intel C++ 15 pybind/pybind11#276 The workaround requires maintaining a fork of pybind11 with patches to work around compiler bugs. Currently, the only workaround needed is a sizeof operation that does not call sizeof: http://stackoverflow.com/questions/1219199/size-of-a-datatype-without-using-sizeof
  • The intel 2015 compiler runs out of memory when building module-md.cc. Workaround: break module-md up into many smaller files. I suspect that mainly it is the pair and wall potentials (templated exports) that cause the high memory usage.
  • possibly more problems I am not aware of...
• Intel 2016
  • Officially supported and tested by pybind11 developers.
  • Untested with hoomd as a whole. I do not currently have access to a system with intel 2016.
  • Large computing centers (i.e. SDSC Comet) are still running 2015.

[joaander]

Eventually centers will upgrade and this will be a non-issue. In the meantime, I still have no way to perform reliable automated testing of Intel compilers, so this remains an unsupported configuration.