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Re: [PATCH] Fix aliasing miscompilation
>>>>> "Jakub" == Jakub Jelinek <firstname.lastname@example.org> writes:
Jakub> If you set it back to -1, it means the restricted pointer
Jakub> now points to an alias set which is a subset of never used
Jakub> alias set, so the end result will be that gcc will assume
Jakub> the restricted pointer cannot ever alias any aggregate of
Jakub> the type it points to, which is bad.
I'm sorry; I should have said alias set zero.
Jakub> So, shouldn't alias.c define a new function which would do
Jakub> exactly what I did in layout_type and frontends would need
Jakub> to call this when they are really finished with type
I think we already have a means of doing that.
There was a lot of discussion in the archives. In the short term, we
really do not want to anything automatic, without the direct
intervention of the front-end. The reason is that in some front-ends
(again, C++ is this way) there are not necessarily FIELD_DECLs for all
things that can appear in the record type.
Please look through the previous emails (look for an exchange between
Kenner and myself) a while back.
Mark Mitchell email@example.com
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