Work on offloading to GPU using gcc/OpenACC

[willend]

Something along the lines of gcc -fopenmp -foffload=-lm -foffload=-latomic -DOPENACC BNL_H8.c -lm

seems to at least provide a compiled binary using gcc 10.

Investigate further. Original and edited BNL_H8.c codes here:

BNL_H8_orig.c.TXT BNL_H8.c.TXT

• naturally segfaults at execution ;-)

[willend]

https://gcc.gnu.org/wiki/Offloading#Compilation_process to educate ourselves, try with simple non-mcstas code first