feat: Enable parameterised precision in the allocator.

Author: semi-h

src/allocator.f90

@@ -1,4 +1,6 @@
 module m_allocator
+   use m_common, only: dp
+
    implicit none
 
    type :: allocator_t
@@ -52,7 +54,7 @@ module m_allocator
      !! field.  User code is currently responsible for incrementing
      !! the reference count.
       type(field_t), pointer :: next
-      real, allocatable :: data(:, :, :)
+      real(dp), allocatable :: data(:, :, :)
       integer :: refcount = 0
       integer :: id !! An integer identifying the memory block.
    end type field_t

src/cuda/allocator.f90

@@ -1,5 +1,7 @@
 module m_cuda_allocator
    use m_allocator, only: allocator_t, field_t
+   use m_common, only: dp
+
    implicit none
 
    type, extends(allocator_t) :: cuda_allocator_t
@@ -8,7 +10,7 @@ module m_cuda_allocator
    end type cuda_allocator_t
 
    type, extends(field_t) :: cuda_field_t
-      real, allocatable, device :: data_d(:, :, :)
+      real(dp), allocatable, device :: data_d(:, :, :)
    end type cuda_field_t
 
    interface cuda_field_t

src/vector3d.f90

@@ -2,6 +2,7 @@ module m_slab
    use m_stencil, only: stencil
    use m_tridiagsolv, only: tridiagsolv
    use m_allocator, only: allocator_t, field_t
+   use m_common, only: dp
 
    implicit none
 
@@ -37,7 +38,7 @@ end subroutine transport_op
    function get_component_ptr(self, i) result(ptr)
       class(slab_t), intent(in) :: self
       integer, intent(in) :: i
-      real, pointer :: ptr(:, :, :)
+      real(dp), pointer :: ptr(:, :, :)
 
       select case (i)
       case (1)