[Bug middle-end/92929] OpenACC/OpenMP 'target' 'exit data'/'update' optimizations

[tschwinge at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92929

--- Comment #4 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
The recent r279626 "OpenACC 2.6 deep copy: middle-end parts" contains changes
related to this (which caused PR93026).

Would've been good to first sort out the desired behavior (this PR92929) before
introducing new functionality (OpenACC 2.6 manual deep copy) that supposedly
depends on these optimizations?

In particular, this needs careful attention, because we have to stay ABI
compatible with existing GCC releases: libgomp needs to do the right things for
both the "old" and the "new" way.  (I'm not claiming that it isn't -- just that
it needs careful attention.)