This issue is an ongoing discussion as you can read here:
https://www.mail-archive.com/gcc-bugs@g ... 54941.html
Please understand that we are hesitant to provide users with any fix as long as we are not sure that this is a compiler problem rather than a vasp bug.
If you follow the discussion on the aforementioned thread and check other websites and codes for this "bug",
you will see that, on the one hand, there are several codes that have the same problem.
On the other hand, there is already an "inofficial" patch for gfortran-8 at following website with no guarantee on our side:
https://patches-gcc.linaro.org/patch/10355/.
It seems that in gfortran-9 the behavior concerning contiguous pointers pointing to non-contiguous targets has been changed again and follows the policy of other compilers, such as
intel, cray, IBM or NAG compilers.
In the meanwhile, please use an older version of gfortran (for instance 7 or 6 have been tested successfully by us), try the newest release of gfortran or use an other compiler.