On Wed, 7 Dec 2022 15:54:42 +0100 Tobias Burnus <tob...@codesourcery.com> wrote:
> Hi Julian, > > If I understand Deepak's comment (on OpenMP.org's omp-lang list, sorry > it is a nonpublic list) correctly, the following wording implies that > a 'from: s.w[z:4]' for a pointer 's.w' also implies a mapping of > 's.w' - if 's' is used inside the target region and, thus, gets > implicitly mapped. > > [TR11 157:21-26] (approx. [5.2 154:22-27], [5.1 352:17-22], [5.0 > 320:22-27]) > > "If a list item with an implicit data-mapping attribute does not have > any corresponding storage in the device data environment prior to a > task encountering the construct associated with the map clause, and > one or more contiguous parts of the original storage are either list > items or base pointers to list items that are explicitly mapped on > the construct, only those parts of the original storage will have > corresponding storage in the device data environment as a result of > the map clauses on the construct." Hmmm... IIRC that is a different conclusion than the one we have understood previously, leading to e.g. the patch here (Chung-Lin CC'ed): https://gcc.gnu.org/pipermail/gcc-patches/2021-May/570075.html Follow-on discussion then questioned whether the change was really the intention of the spec, but we thought it was. Has that changed now? (I think actually changing the behaviour is a matter of flipping a switch, but let's make sure we choose the right setting!) Thanks, Julian
