Unit tests do not build with Serial backend

[ndellingwood]

After generating a makefile with the Serial backend only and running make build-test, no unit tests are built. This occurred with gcc 5.4.

Script used to generate makefile:

KOKKOS_PATH=${HOME}/Research/kokkos_items/kokkos #path to kokkos source
KOKKOSKERNELS_SCALARS=double #the scalar types to instantiate =double,float...
KOKKOSKERNELS_LAYOUTS=LayoutLeft #the layout types to instantiate.
KOKKOSKERNELS_ORDINALS=int #ordinal types to instantiate
KOKKOSKERNELS_OFFSETS=int #offset types to instantiate
KOKKOSKERNELS_PATH=../.. #path to kokkos-kernels top directory.
CXX=g++ #${KOKKOS_PATH}/config/nvcc_wrapper #icpc #
KOKKOSKERNELS_OPTIONS=eti-only #options for kokkoskernels
KOKKOS_DEVICES=Serial # other devices Cuda,Serial ..
KOKKOS_ARCHS=
CXXFLAGS="-Wall -pedantic -Werror -O3 -g -Wshadow -Wsign-compare -Wtype-limits -Wuninitialized"

../../scripts/generate_makefile.bash --kokkoskernels-path=${KOKKOSKERNELS_PATH} --with-scalars=${KOKKOSKERNELS_SCALARS} --with-ordinals=${KOKKOSKERNELS_ORDINALS} --with-offsets=${KOKKOSKERNELS_OFFSETS} --kokkos-path=${KOKKOS_PATH} --with-devices=${KOKKOS_DEVICES} --arch=${KOKKOS_ARCHS} --compiler=${CXX} --with-options=${KOKKOSKERNELS_OPTIONS}  --cxxflags="${CXXFLAGS}"

[ndellingwood]

Added some $(info ...) statements to unit_tests/Makefile to see what variables were/weren't being set.
By generating makefile as in previous statement:

• KOKKOS_INTERNAL_USE_SERIAL is not set to 1.
• KOKKOSKERNELS_INTERNAL_TEST_SERIAL is never set as a result, hence the unit tests never compiling
• KOKKOSKERNELS_INTERNAL_INST_EXECSPACE_SERIAL is set 1

[ndellingwood]

After Makefile.kokkos-kernels includes Makefile.kokkos (from KOKKOS_PATH=${KOKKOSKERNELS_PATH}/../kokkos), KOKKOS_INTERNAL_USE_SERIAL is undefined, though when I add info messages within my clone of Kokkos KOKKOS_INTERNAL_USE_SERIAL is set to 1.

From the print statements from Makefile.kokkos-kernels during compilation:

echo "# Kokkos Internal Settings" >> /Users/ndellin/Research/kokkos_items/kokkos-kernels/testing/Serial-gcc/install/Makefile.kokkos-kernels
echo "KOKKOS_INTERNAL_USE_CUDA = 0" >> /Users/ndellin/Research/kokkos_items/kokkos-kernels/testing/Serial-gcc/install/Makefile.kokkos-kernels
echo "KOKKOS_INTERNAL_USE_OPENMP = 0" >> /Users/ndellin/Research/kokkos_items/kokkos-kernels/testing/Serial-gcc/install/Makefile.kokkos-kernels
echo "KOKKOS_INTERNAL_USE_SERIAL = " >> /Users/ndellin/Research/kokkos_items/kokkos-kernels/testing/Serial-gcc/install/Makefile.kokkos-kernels
echo "KOKKOS_INTERNAL_USE_PTHREADS = 0" >> /Users/ndellin/Research/kokkos_items/kokkos-kernels/testing/Serial-gcc/install/Makefile.kokkos-kernels
...

Also, from my testing/kokkos/install directory, KOKKOS_INTERNAL_USE_SERIAL does not appear in the Makefile.kokkos file; the other exec spaces are set to 0. Last several lines of the file pasted below:

#Internal settings which need to propagated for Kokkos examples
KOKKOS_INTERNAL_USE_CUDA = 0
KOKKOS_INTERNAL_USE_OPENMP = 0
KOKKOS_INTERNAL_USE_PTHREADS = 0
KOKKOS_INTERNAL_USE_ROCM = 0
KOKKOS_INTERNAL_USE_QTHREADS = 0

#Fake kokkos-clean target
kokkos-clean:

[ndellingwood]

Alright, chased this down to a bug in Kokkos in core/src/Makefile.generate_build_files, lines to append KOKKOS_INTERNAL_USE_SERIAL when generating the Makefile.kokkos were missing, so KOKKOS_INTERNAL_USE_SERIAL definition never propogated to Kokkos-Kernels.
Fixed the bug locally and will issue a PR to Kokkos and will cross-reference here.

[ndellingwood]

I opened Kokkos issue # 1418 regarding the issue and PR # 1419 with the fix.

[ndellingwood]

Not sure how to label this since the bug is in Kokkos, not Kokkos-Kernels...