The error message:
mod_matrices.o:(.data+0x1790): undefined reference to `allocator_rank_2_sub_'
The module mMatrices (in mod_matrices.f08) calls the function allocator_rank_2_sub
which is in a submodule smAllocations (in mod_sub_matrices_allocators.f08). The code worked before breaking the module mMatrices
into a module and a submodule.
The module:
module mMatrices
use mPrecisionDefinitions, only : ip, rp
implicit none
type :: matrices
real ( rp ), allocatable :: A ( : , : ), AS ( : , : ), ASAinv ( : , : )
contains
private
procedure, nopass, public :: allocator_rank_2 => allocator_rank_2_sub
procedure, public :: construct_matrices => construct_matrices_sub
end type matrices
private :: allocator_rank_2_sub
private :: construct_matrices_sub
interface
subroutine allocator_rank_2_sub ( array, rows, cols )
use mPrecisionDefinitions, only : ip, rp
real ( rp ), allocatable, intent ( out ) :: array ( : , : )
integer ( ip ), intent ( in ) :: rows, cols
end subroutine allocator_rank_2_sub
end interface
contains
subroutine construct_matrices_sub ( me, ints, mydof, measure )
...
call me % allocator_rank_2 ( me % A, m, mydof )
...
end subroutine construct_matrices_sub
end module mMatrices
The submodule:
submodule ( mMatrices ) smAllocations
contains
module subroutine allocator_rank_2_sub ( array, rows, cols )
...
end subroutine allocator_rank_2_sub
end submodule smAllocations
The compilation via make:
ftn -g -c -r s -o mod_precision_definitions.o mod_precision_definitions.f08
...
ftn -g -c -r s -o mod_matrices.o mod_matrices.f08
...
ftn -g -c -r s -o mod_sub_matrices_allocators.o mod_sub_matrices_allocators.f08
...
ftn -g -c -r s -o lsq.o lsq.f08
ftn -g -o lsq lsq.o --- mod_matrices.o --- mod_precision_definitions.o --- mod_sub_matrices_allocators.o ---
mod_matrices.o:(.data+0x1790): undefined reference to `allocator_rank_2_sub_'
make: *** [lsq] Error 1
The last portion of `makefile'
# Main program depends on all modules
$(PRG_OBJ) : $(MOD_OBJS)
# resolve module interdependencies
...
mod_matrices.o : mod_precision_definitions.o mod_parameters.o mod_intermediates.o
mod_sub_matrices_allocators.o : mod_matrices.o
...
The machine: Cray XC30
The compiler: Fortran 5.2.82
The question: What needs to be fixed?
The corrected code fragment incorporating @IanH's fix:
interface
MODULE subroutine allocator_rank_2_sub ( array, rows, cols )
use mPrecisionDefinitions, only : ip, rp
real ( rp ), allocatable, intent ( out ) :: array ( : , : )
integer ( ip ), intent ( in ) :: rows, cols
end subroutine allocator_rank_2_sub
end interface