# Does ifort ignore locality specifiers in do concurrent?

**URL:** <https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723>\
**Category:** Help\
**Created:** [August 19, 2021, 5:05pm UTC](https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723 "2021-08-19T17:05:46Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![hsnyder](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/hsnyder/32/747_2.png) [@hsnyder](https://fortran-lang.discourse.group/u/hsnyder)\
**Post date:** [August 19, 2021, 5:05pm UTC](https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723/1 "2021-08-19T17:05:46Z")

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Does anybody know if ifort actually pays attention to the locality specifiers in `do concurrent` ? Unless I’ve misunderstood the standard (quite possible), the following should not compile, but does:

```auto
module m_demo
      implicit none
contains

      function demo_f(a,b)
          real, contiguous, intent(in) :: a(:), b(:)
          real :: demo_f(size(a))

          do concurrent (integer :: i = 1:size(a)) default(none)
            demo_f(i) = sin(a(i)) + exp(b(i))
          end do
      end function

end module

```

If I use the `-parallel -qopt-report=3` options do get `ifort` to automatically parallelize `do concurrent`, I see in the optimization report a section like:

```
remark #17109: LOOP WAS AUTO-PARALLELIZED
remark #17101: parallel loop shared={ } private={ } firstprivate={ ? i } lastprivate={ } firstlastprivate={ } reduction={ }

```

And I’ve noticed that even if I add `shared()` or `local()` or `local_init()` clauses to the `do concurrent` statement, it always puts all the variables in `firstprivate` in the optimization report.

Is this is a bug, or if my expectations are wrong? Thanks.

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<div class="post-metadata">

**Author:** ![Beliavsky](https://avatars.discourse-cdn.com/v4/letter/b/ba8739/32.png) [@Beliavsky](https://fortran-lang.discourse.group/u/Beliavsky)\
**Post date:** [August 19, 2021, 5:37pm UTC](https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723/2 "2021-08-19T17:37:53Z")

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I cannot answer the OP’s question but will note that gfortran 12.0.0 20210718 from [equation.com](http://equation.com) compiles the code if `i` is declared earlier and if `default(none)` is removed (what does that do?). So this compiles:

```auto
module m_demo
      implicit none
contains

      function demo_f(a,b)
          real, contiguous, intent(in) :: a(:), b(:)
          real :: demo_f(size(a))
          integer :: i
          do concurrent (i = 1:size(a))
            demo_f(i) = sin(a(i)) + exp(b(i))
          end do
      end function

end module

```

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**Author:** ![sblionel](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/sblionel/32/853_2.png) [@sblionel](https://fortran-lang.discourse.group/u/sblionel)\
**Post date:** [August 19, 2021, 8:35pm UTC](https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723/3 "2021-08-19T20:35:32Z")

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I would expect the compiler to require you to specify the locality of the other variables in the block. I suggest you report this to Intel. As far as I know, it does process locality specifiers. When I try your example in 2021.3, it tells me that the loop is not parallelized due to insufficient work.

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<div class="post-metadata">

**Author:** ![hsnyder](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/hsnyder/32/747_2.png) [@hsnyder](https://fortran-lang.discourse.group/u/hsnyder)\
**Post date:** [August 19, 2021, 9:19pm UTC](https://fortran-lang.discourse.group/t/does-ifort-ignore-locality-specifiers-in-do-concurrent/1723/4 "2021-08-19T21:19:26Z")

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@sblionel True, I should have mentioned that in order to get it to auto-parallelize, I added `!dir$ loop count min(512)` directly above the loop.

But thanks for the sanity check - I’ll let Intel know and see what they say.