[PATCH] D52268: [AST] Squeeze some bits in LinkageComputer

[Erich Keane via Phabricator via cfe-commits]

erichkeane added subscribers: gbiv, george.burgess.iv.
erichkeane added a comment.

In https://reviews.llvm.org/D52268#1239557, @riccibruno wrote:

> In https://reviews.llvm.org/D52268#1239538, @erichkeane wrote:
>
> > Does this still work with 32 bit hosts?  Does PointerIntPair have 3 bits in that case?  Is the alignof static_assert valid in that case?
>
>
> I think it does since Decl is manually over-aligned to 8 bytes. But you are right that the static_assert is probably not needed
>  here since llvm::PointerIntPair checks that the low bits are available.
>
> > I'm not sure how often this ever gets modified, but it is a touch scary to me that we've already maxed out the size of this struct.
>
> I am not sure either... It was just a quick change I spotted and this is borderline not worth doing. If you think that we ought to keep
>  some space left I will abandon this revision.


I did a little digging on this, and it seems to be to keep track of a declarations linkage for caching sake.  Unless the committees change linkage at all, I guess I don't see this changing much.  I think my concerns are assuaged.

That said, I'm adding @george.burgess.iv (or @gbiv ?) to the review, since he's the original author.


Repository:
  rC Clang

https://reviews.llvm.org/D52268