[PATCH] D89544: [CodingStandards] Clarify the recommendation to use SmallVector

Fri Oct 16 05:24:38 PDT 2020

gribozavr2 added reviewers: jdoerfert, rjmccall.
gribozavr2 added a comment.

In D89544#2334494 <https://reviews.llvm.org/D89544#2334494>, @lebedev.ri wrote:

> What reasoning was used in the patch that added that wording?

https://reviews.llvm.org/D74340

> IIRC `llvm::SmallVector` is better than `std::vector` also because
> former doubles the allocation size instead of just increasing it.

`std::vector` must also use a multiplicative strategy in order to provide O(1) `push_back`. The C++ standard does not guarantee the specific factor though.

As written, the wording can be read to suggest to use `llvm::SmallVector<T, 0>` instead of `std::vector<T>`. Is that the intent?

Repository:
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  https://reviews.llvm.org/D89544/new/

https://reviews.llvm.org/D89544