Pgfotran hangs while compiling this simple program

Hi,
I downloaded today the NVIDIA HPC Software Development Kit ( Bundled with the newest CUDA version (11.4)) and I am running it on Ubuntu 21.04 LTS. I cannot compile this program attached:
addition.f90 (345 Bytes)
I tried:
pgfortran -acc addition.f90 -o fast_addition.exe

however I can compile with:
gfortran addition.f90 -fopenacc -o fast.exe

How can I make it work with pgfortran?

Thank you for the help

nvfortran (aka pgfortran) can compile this, it just takes awhile. The problem being this line:

real, dimension(15000,20000) :: Mat = 0.

Static initialization of a fixed size array means that the compiler needs to set-up the BSS section to contain the initialization on load of the program which can take time as this is done per element. Better to change this to runtime initialization:

% cat addition.f90
      program addition

        integer :: i, j
        real, dimension(15000,20000) :: Mat
        Mat=0.

        i = 0
        j = 0
!$acc parallel loop
        do i = 1,15000
          do j = 1,20000
            Mat(i,j) = i+j
          enddo
        enddo
!$acc end parallel loop
        print *,Mat(10000,20000)
      end program addition

% time nvfortran addition.f90 -acc
0.880u 0.147s 0:01.14 89.4%     0+0k 0+632io 0pf+0w
% a.out
    30000.00

Thanks a lot for the explanation

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.