https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111503
Bug ID: 111503
Summary: Issues with POINTER, OPTIONAL, CONTIGUOUS dummy
arguments
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: anlauf at gcc dot gnu.org
Target Milestone: ---
The following code shows an issue that popped up while looking at pr55978:
program test
implicit none
integer, pointer, contiguous :: p(:) => null()
print *, is_contiguous (p)
call one (p) ! accepted
call one () ! accepted (but see pr55978 comment#19)
call one (null()) ! rejected, but accepted by NAG, Intel
call one (null(p)) ! rejected by NAG, accepted by Intel
contains
subroutine one (x)
integer, pointer, optional, contiguous, intent(in) :: x(:)
! integer, optional, contiguous, intent(in) :: x(:) ! accepted
end subroutine one
end
Intel accepts the code as-is. NAG complains that NULL(p) is not contiguous:
Error: pr11xxxx.f90, line 8: Argument X (no. 1) of ONE is a CONTIGUOUS pointer,
but the actual argument NULL(P) is not simply contiguous
I guess that NAG is correct here, and Intel does not properly diagnose.
gfortran is maybe overly "cautious" and gives:
pr11xxxx.f90:7:12:
7 | call one (null()) ! rejected, but accepted by NAG, Intel
| 1
Error: Actual argument to contiguous pointer dummy 'x' at (1) must be simply
contiguous
pr11xxxx.f90:8:12:
8 | call one (null(p)) ! rejected by NAG, accepted by Intel
| 1
Error: Actual argument to contiguous pointer dummy 'x' at (1) must be simply
contiguous
As - in the current context - null() is equivalent to an absent actual
argument, I wonder whether we should relax our checks and follow NAG and Intel.
