Array bounds checking with Intel compiler: false positive

[Harald1]

The Intel compiler appears to be somewhat special with array bounds checking. When array expressions (like slices) are involved, -check bounds does not trigger. The suggested "correct" version is -check shape, which however has annoying false positives.

Example:

subroutine test (j,js,si)
implicit none
integer :: js(3,2), j(10,2), si(1,3)
js(:,:) = j(si(1,:),:)
js(1:3,1:2) = j(si(1,1:3),1:2)
end subroutine test

% ifort -V -check shape -c ifort-shape.f90
Intel(R) Fortran Intel(R) 64 Compiler Classic for applications running on Intel(R) 64, Version 2021.1 Build 20201112_000000
Copyright (C) 1985-2020 Intel Corporation. All rights reserved.

Intel(R) Fortran 2021.1-2085
ifort-shape.f90(4): error #5581: Shape mismatch: The extent of dimension 1 of array JS is 3 and the corresponding extent of array J is 1
js(:,:) = j(si(1,:),:)
----------------^
ifort-shape.f90(5): error #5581: Shape mismatch: The extent of dimension 1 of array JS is 3 and the corresponding extent of array J is 1
js(1:3,1:2) = j(si(1,1:3),1:2)
----------------^
compilation aborted for ifort-shape.f90 (code 1)

I hope this can be fixed some day...

Harald

[Devorah_H_Intel · Accepted solution]

"I hope this can be fixed some day..."

This has been fixed already. Be on the lookout for the upcoming 2021.2 ifort.

[Harald1]

This is good news.

Thanks!

[Harald1]

Indeed it is fixed in ifort 2021.2.0.  (The -check options seem to be not yet implemented in ifx).

Thanks,

Harald