https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81581
Bug ID: 81581
Summary: runtime checks for DIM argument of intrinsic SUM
missing
Product: gcc
Version: 7.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: janus at gcc dot gnu.org
Target Milestone: ---
Please consider this test case:
program summation
integer, dimension(1:10,1:10) :: arr
integer :: i
do i=1,10
arr(i,:) = i
end do
! print *, sum(arr, 5) ! compile-time error: "not a valid dimension index"
call print_sum(1)
call print_sum(2)
call print_sum(5)
contains
subroutine print_sum(d)
integer, intent(in) :: d
print *, sum(arr, d)
end subroutine
end
The commented line correctly generates a compile-time error. However, when the
DIM argument to SUM is not a compile-time constant, wrong values are accepted
and the program runs without any error or warning, producing the output:
55 55 55 55 55 55
55 55 55 55
10 20 30 40 50 60
70 80 90 100
0 0 0 0 0 0
0 0 0 0
I guess one should implement a runtime check that is enabled by -fcheck=all.
(One could possibly include it into -fcheck=bounds?)
