libgomp: Fix reverse offload issues
If there is nothing to map, skip the mapping and avoid attempting to
copy 0 bytes from addrs, sizes and kinds.
Additionally, it could happen that a non-allocated address was deallocated,
such as a pointer set, leading to a free for the actual data.
* target.c (gomp_target_rev): Handle mapnum == 0 and avoid
freeing not allocated memory.
* testsuite/libgomp.fortran/reverse-offload-6.f90: New test.
(cherry picked from commit 0b1ce70a813b98ef2893779d14ad6c90c5d06a71)
3 files changed