I build the code:

program main

use accel_lib

integer :: n ! size of the vector

real,dimension(:),allocatable :: a ! the vector

real,dimension(:),allocatable :: r ! the results

real,dimension(:),allocatable :: e ! expected results

integer :: i

integer :: c0, c1, c2, c3, cgpu, chost

character(10) :: arg1

if( iargc() .gt. 0 )then

call getarg( 1, arg1 )

read(arg1,’(i10)’) n

else

n = 100000

endif

if( n .le. 0 ) n = 100000

allocate(a(n))

allocate(r(n))

allocate(e(n))

do i = 1,n

a(i) = i*2.0

enddo

call acc_init( acc_device_nvidia )

call system_clock( count=c1 )

!$acc region

do i = 1,n

r(i) = sin(a(i)) ** 2 + cos(a(i)) ** 2

enddo

!$acc end region

call system_clock( count=c2 )

cgpu = c2 - c1

do i = 1,n

e(i) = sin(a(i)) ** 2 + cos(a(i)) ** 2

enddo

call system_clock( count=c3 )

chost = c3 - c2

! check the results

do i = 1,n

if( abs(r(i) - e(i)) .gt. 0.000001 )then

print *, i, r(i), e(i)

endif

enddo

print *, n, ’ iterations completed’

print *, cgpu, ’ microseconds on GPU’

print *, chost, ’ microseconds on host’

end program

Then:

Linking…

ConsoleApp.obj : error LNK2019: unresolved external symbol acc_init_ referenced in function MAIN_

Why? I need your help Mat,thank you!