Several issues with new CMake build infrastructure (reported by Eric Phipps)

[etphipp]

I have a (non-Trilinos) project that builds Kokkos with CMake inline with the rest of the project, and I have come across a few issues with the CMake build infrastructure that was updated recently (this is with the latest Kokkos master).

1. You now have to use CMake version 3.3 or greater, even though it only checks for version 3.1 or greater. The issue is in kokkos_build.cmake you have

target_compile_options(
    kokkoscore
    PUBLIC $<$<COMPILE_LANGUAGE:CXX>:${KOKKOS_CXX_FLAGS}>
  )

and $<COMPILE_LANGUAGE:CXX> is a valid generator expression only in cmake 3.3 or greater. With 3.2.2 I get

  Error evaluating generator expression:

    $<COMPILE_LANGUAGE:CXX>

  Expression did not evaluate to a known generator expression

2. There appears to be no way to set the HWLOC path. If I enable HWLOC and set KOKKOS_HWLOC_DIR to its installation directory, I get:

/home/etphipp/project/tensors/genten/genten/kokkos/core/src/impl/Kokkos_hwloc.cpp:221:19: fatal error: hwloc.h: No such file or directory
 #include <hwloc.h>

Looking through the CMake logic in Kokkos, it appears that KOKKOS_HWLOC_DIR is a valid option, but it is never used anywhere. Setting HWLOC_PATH doesn't work either.

3. At the end of the configure, Kokkos spews out some annoying output:

CMake Warning at kokkos/cmake/tribits.cmake:6 (MESSAGE):
  The project name is: Kokkos
Call Stack (most recent call first):
  kokkos/CMakeLists.txt:50 (include)


-- ProjectName: Kokkos
-- Tests: OFF
-- ProjectName: Kokkos
-- Tests: OFF
-- ProjectName: Kokkos
-- Tests: OFF
-- ProjectName: Kokkos
-- Tests: OFF
-- ProjectName: Kokkos
-- Tests: OFF

It would be nice if this could be cleaned up.

[etphipp]

Another issue:
4. If I make a CMakeLists.txt change and run "make" as usual, I now get the error:

CMake Error at kokkos/cmake/kokkos_settings.cmake:20 (message):
  SNB,Kepler35 is not an accepted value for KOKKOS_ARCH.  Please pick from
  these choices: None

         AMDAVX
         ARMv80
         ARMv81
         ARMv8-ThunderX
         WSM
         SNB
         HSW
         BDW
         SKX
         KNC
         KNL
         BGQ
         Power7
         Power8
         Power9
         Kepler
         Kepler30
         Kepler32
         Kepler35
         Kepler37
         Maxwell
         Maxwell50
         Maxwell52
         Maxwell53
         Pascal60
         Pascal61

It looks to me that the KOKKOS_ARCH list I specify as

-D KOKKOS_ARCH="SNB;Kepler35"

is internally being transformed to "SNB,Kepler35", which is no longer valid CMake list syntax. To work around this I now have to blow away the CMakeCache.txt and reconfigure from scratch each time I make a change that requires a reconfigure.

[mhoemmen]

(following)

[ibaned]

@etphipp Thanks for reporting!
My recent pull request #1361 should fix the 4th item you raised.
Also my pull request #1346 fixes part of the annoying output (the warning in the 3rd item), but not the repeated stuff after it.

[crtrott]

We can kill that project output alltogether, I don't think we care.

[ibaned]

@etphipp I just created a branch and pull request to fix all the remaining issues: #1382. Would you be able to check out that branch and confirm whether it fixes all of this for you?

[etphipp]

HWLOC is still not working. I have -D KOKKOS_HWLOC_DIR=/usr/local/software/hwloc/current and you can see that it still isn't being added to the include path:

[  1%] Building CXX object kokkos/CMakeFiles/kokkos.dir/core/src/impl/Kokkos_hwloc.cpp.o
cd /home/etphipp/project/tensors/genten/build/opt_intel_inline/kokkos && /home/software/intel/compilers_and_libraries_2017.4.196/linux/bin/intel64/icpc    -I/home/etphipp/project/tensors/genten/genten/kokkos/core/src -I/home/etphipp/project/tensors/genten/genten/kokkos/containers/src -I/home/etphipp/project/tensors/genten/genten/kokkos/algorithms/src -I/home/etphipp/project/tensors/genten/build/opt_intel_inline/kokkos  -g -xHost -restrict -gxx-name=g++-4.9 -g   --std=c++11 -mavx -fopenmp -o CMakeFiles/kokkos.dir/core/src/impl/Kokkos_hwloc.cpp.o -c /home/etphipp/project/tensors/genten/genten/kokkos/core/src/impl/Kokkos_hwloc.cpp
/home/etphipp/project/tensors/genten/genten/kokkos/core/src/impl/Kokkos_hwloc.cpp(221): catastrophic error: cannot open source file "hwloc.h"
  #include <hwloc.h>

[ibaned]

I think all the items in this issue have been fixed after a series of several pull requests. This will all be available on master and in Trilinos at the next Kokkos release.