I believe I finally found a nasty compiler bug. Starting with compiler version intel/2017.5.239 up to the most recent avaiable for me intel/2019.0.117, there is a problem with pointing to a component of an allocated derived type. Opposing to the expectation using the pointer modifies always the first component of type instead of the one that it is pointing to. The following minimal reproducer compiled with -O0 returns:
F F
In the example it is only output, however, it works also wrong for modifying, even with the type components have different POD types. The intel compiler 2016 and earlier shows the expected behavoir.
PROGRAM main
IMPLICIT NONE
TYPE t_traj
LOGICAL :: a = .FALSE.
LOGICAL :: b = .TRUE.
END TYPE t_traj
INTEGER, PARAMETER :: noPart = 3
TYPE(t_traj), TARGET, ALLOCATABLE :: sps(:)
LOGICAL, POINTER :: p_point(:)
ALLOCATE( sps(noPart) )
p_point(1:noPart-1) => sps(1:noPart-1)%b
WRITE(*,*) p_point
DEALLOCATE( sps )
END PROGRAM main
