https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92311
Bug ID: 92311
Summary: Fortran and OpenMP use_device_ptr and OpenACC
attach_ptr/dettach_ptr
Product: gcc
Version: 9.2.0
Status: UNCONFIRMED
Keywords: openacc, openmp
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: naromero at anl dot gov
CC: jakub at gcc dot gnu.org
Target Milestone: ---
Host: x86-64 westmere
Target: NVidia GPU
Build: x86_64-pc-linux-gnu
Created attachment 47152
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47152&action=edit
Test OpenMP use_device_ptr and OpenACC dettach/attach
I attach a simple isolated reproducer that reproduces the issue from a more
complicated scientific code.
The attached file contains both an OpenACC and OpenMP version of the same
program. The OpenACC program build and runs correctly with the latest PGI
Fortran compiler. The OpenMP program also builds and runs with the latest IBM
XL Fortran compiler.
The bug is against the frontend of the Fortran compiler that handles directives
in both OpenACC and OpenMP for NVidia GPUs. Here is the compile-time error with
-fopenmp:
The error for the OpenMP is shown below:
29 | !$omp target data use_device_ptr(this_bin)
| 1
Error: TARGET DATA must contain at least one MAP clause at (1)
AFAIK, this is not a correct interpretation of the standard. You don't need a
map clause here, use_device_ptr clause is enough.
https://www.openmp.org/spec-html/5.0/openmpsu57.html#x83-2580002.12.2
For the OpenACC program, it may be that this is part of the OpenACC spec that
has not been implemented yet. Here is the error with -fopenacc:
test_openacc_attach.F90:27:9:
27 | !$acc enter data attach(this_bin)
| 1
Error: Unclassifiable OpenACC directive at (1)
test_openacc_attach.F90:46:9:
46 | !$acc exit data detach(this_bin)
| 1
Error: Unclassifiable OpenACC directive at (1)
