PGI compiler bug: datatype not supported

[lisanhu]

When optimizing memory consumption of the tool, the original working OpenACC multicore code doesn't work. The error message says:

single_end:
    306, Accelerator region ignored
    307, Accelerator restriction: invalid loop
    390, Accelerator restriction: datatype not supported: .Q0045
PGC/x86-64 Linux 18.10-1: compilation completed with severe errors

The data type it refers to is the result data structure. I changed a few char * to mstring to save memory.

Then I find a workaround: the original code is using fields initializer (result r = {.loc = loc, ...}). I change that part to default initializer and manually assign the values to the fields. The code could compile in this way.

This problem seems to be a compiler bug. My guess of the failure is that the mstring introduce a few function call during the initialization, which might produce the problem.