rsmith added inline comments.
================ Comment at: lib/AST/MicrosoftCXXABI.cpp:253 + + MPI.HasPadding = MPI.Width % MPI.Align == 0; ---------------- rsmith wrote: > erichkeane wrote: > > rsmith wrote: > > > This seems to be backwards? > > > > > > Also, I'm not sure whether this is correct. In the strange case where > > > `Width` is not a multiple of `Align` (because we don't round up the > > > width), there is no padding. We should only set `HasPadding` to `true` in > > > the `alignTo` case below. > > I think you're right about it being backwards. > > > > However, doesn't the struct with a single Ptr and either 1 or 3 Ints have > > tail padding as well? I do believe you're right about the alignTo > > situation below, but only if Width changes, right? > I think the idea is that a struct with one pointer and an odd number of ints, > on 32-bit Windows, will have no padding per se, but its size will simply not > be a multiple of its alignment. (So struct layout can put things in the four > bytes after it, but will insert padding before it to place it at an 8 byte > boundary.) See example here: https://godbolt.org/g/Nr8C2L https://reviews.llvm.org/D39347 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
