https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105687
Bug ID: 105687
Summary: non-contiguous data in assumed rank
Product: gcc
Version: 12.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: martin.diehl at kuleuven dot be
Target Milestone: ---
Created attachment 53014
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53014&action=edit
small reproducer
When passing a strided array to a select-rank statement, the information that
that data is non-contiguous is somehow lost. At least when further passing the
data to an assumed-size function, the arriving data differs.
Note: This might be related to bug 105674. This report illustrates the actual
problem I've encountered (wrong data) while the other report shows intermediate
results when trying to write a minimal reproducer.
code
====
program test
integer, dimension(2,2), target :: dim_2
integer, dimension(:,:), pointer :: strided
integer :: i
dim_2 = reshape([(i,i=1,size(dim_2))],shape(dim_2))
strided => dim_2(1:1,:)
print*, 'is_contiguous(strided)', is_contiguous(strided)
print*, 'is_contiguous((strided))', is_contiguous((strided))
print*, ''
print*, 'call show(strided)'
call show(strided,size(strided))
print*, 'call show((strided))'
call show((strided),size((strided)))
print*, 'call assumed_rank(strided)'
call assumed_rank(strided)
print*, 'call assumed_rank((strided))'
call assumed_rank((strided))
contains
subroutine assumed_rank(dataset)
integer, intent(in), dimension(..) :: dataset
select rank(dataset)
rank(2)
print*, 'is contiguous in select', is_contiguous(dataset)
print*, 'data in select', dataset
call show(dataset,size(dataset))
end select
print*, ''
end subroutine assumed_rank
subroutine show(dataset,s)
integer, intent(in) :: s
integer, intent(in), dimension(*) :: dataset
print*, 'is contiguous in show', is_contiguous(dataset)
print*, 'data in show', dataset(1:s)
print*, ''
end subroutine show
end program test
output
======
is_contiguous(strided) F
is_contiguous((strided)) T
call show(strided)
is contiguous in show T
data in show 1 3
call show((strided))
is contiguous in show T
data in show 1 3
call assumed_rank(strided)
is contiguous in select T
data in select 1 3
is contiguous in show T
data in show 1 2
call assumed_rank((strided))
is contiguous in select T
data in select 1 3
is contiguous in show T
data in show 1 3
