Crash when writing parallel compressed chunks


Just an observation from a run compiled with 1.10.6 + the patch provided by @jhenderson earlier in this discussion chain.

When the 2nd H5Dcreate call is moved to before the 1st H5Dwrite in @jrichardshaw’s test program, the error was gone. It looks like the problem occurs when calls to H5Dcreate and H5Dwrite are interleaved.

After reading into file H5C.c and adding a few printf statements, it appears that values of entry_ptr->coll_access checked in line 2271 are not consistent among the 4 running processes, which causes only 2 of the 4 processes calling MPI_Bcast at line 2297, and thus the error.