[Numpy-discussion] Problem with compiling openacc with f2py

Vikram Singh

2016-10-30 14:12:27 UTC

Ok, I got it to compile using

f2py -c -m --f90flags='-fopenmp -fopenacc -foffload=nvptx-none -foffload=-O3
-O3 -fPIC' hello hello.f90 -L/usr/local/cuda/lib64 -lcublas -lcudart
-lgomp

But now I get the import error,
/home/Experiments/fortran_python/hello.cpython-35m-x86_64-linux-gnu.so:
undefined symbol: __offload_func_table

Seems to me I have to link another library. But where is __offload_func_table

Post by Vikram Singh
I am a newbie to f2py so I have been creating simple test cases.
Eventually I want to be able to use openacc subroutine from python. So
here's the test case
module test
use iso_c_binding, only: sp => C_FLOAT, dp => C_DOUBLE, i8 => C_INT
use omp_lib
use openacc
implicit none
contains
subroutine add_acc (a, b, n, c)
integer(kind=i8), intent(in) :: n
real(kind=dp), intent(in) :: a(n)
real(kind=dp), intent(in) :: b(n)
real(kind=dp), intent(out) :: c(n)
integer(kind=i8) :: i
!$acc kernels
do i = 1, n
c(i) = a(i) + b(i)
end do
!$acc end kernels
end subroutine add_acc
subroutine add_omp (a, b, n, c)
integer(kind=i8), intent(in) :: n
real(kind=dp), intent(in) :: a(n)
real(kind=dp), intent(in) :: b(n)
real(kind=dp), intent(out) :: c(n)
integer(kind=i8) :: i, j
!$omp parallel do
do i = 1, n
c(i) = a(i) + b(i)
end do
!$omp end parallel do
end subroutine add_omp
subroutine nt (c)
integer(kind=i8), intent(out) :: c
c = omp_get_max_threads()
end subroutine nt
subroutine mult (a, b, c)
real(kind=dp), intent(in) :: a
real(kind=dp), intent(in) :: b
real(kind=dp), intent(out) :: c
c = a * b
end subroutine mult
end module test
I compile using
f2py -c -m --f90flags='-fopenacc -foffload=nvptx-none -foffload=-O3
-O3 -fPIC' hello hello.f90 -L/usr/local/cuda/lib64 -lcublas -lcudart
-lgomp
Now, until I add the acc directives everything works fine. But as soon
as I add the acc directives I get this error.
gfortran:f90: /tmp/tmpld6ssow3/src.linux-x86_64-3.5/hello-f2pywrappers2.f90
/home//Experiments/Nvidia/OpenACC/OLCFHack15/gcc6/install/bin/gfortran
-Wall -g -Wall -g -shared
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/hellomodule.o
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/fortranobject.o
/tmp/tmpld6ssow3/hello.o
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/hello-f2pywrappers2.o
-L/usr/local/cuda/lib64 -L/home//usr/local/miniconda/lib -lcublas
-lcudart -lgomp -lpython3.5m -lgfortran -o
./hello.cpython-35m-x86_64-linux-gnu.so
/usr/bin/ld: /tmp/cc2yQ89d.target.o: relocation R_X86_64_32 against
`.rodata' can not be used when making a shared object; recompile with
-fPIC
/tmp/cc2yQ89d.target.o: error adding symbols: Bad value
collect2: error: ld returned 1 exit status
/usr/bin/ld: /tmp/cc2yQ89d.target.o: relocation R_X86_64_32 against
`.rodata' can not be used when making a shared object; recompile with
-fPIC
/tmp/cc2yQ89d.target.o: error adding symbols: Bad value
collect2: error: ld returned 1 exit status
error: Command "/home//Experiments/Nvidia/OpenACC/OLCFHack15/gcc6/install/bin/gfortran
-Wall -g -Wall -g -shared
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/hellomodule.o
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/fortranobject.o
/tmp/tmpld6ssow3/hello.o
/tmp/tmpld6ssow3/tmp/tmpld6ssow3/src.linux-x86_64-3.5/hello-f2pywrappers2.o
-L/usr/local/cuda/lib64 -L/home//usr/local/miniconda/lib -lcublas
-lcudart -lgomp -lpython3.5m -lgfortran -o
./hello.cpython-35m-x86_64-linux-gnu.so" failed with exit status 1
I don't get why just putting acc directives should create errors, when
omp does not.
Vikram