[PATCH] D49163: ADT: Shrink SmallVector size 0 to 16B on 64-bit platforms

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

@rsmith, what's the least bad way to do what SmallVector is trying to do?



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Comment at: llvm/include/llvm/ADT/SmallVector.h:90
+        reinterpret_cast<const char *>(this) +
+        offsetof(SmallVectorAlignmentAndSize<T>, FirstEl)));
+  }
----------------
This assumes that base classes are laid out more or less the same as fields, but we were already assuming that there wouldn't be padding between FirstEl and InlineElts, so this seems like an improvement.


https://reviews.llvm.org/D49163