[llvm] [SmallPtrSet] Don't leave tombstones in small mode (PR #96762)

[Jakub Kuderski via llvm-commits]

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@@ -362,6 +364,22 @@ class SmallPtrSetImpl : public SmallPtrSetImplBase {
   template <typename UnaryPredicate>
   bool remove_if(UnaryPredicate P) {
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kuhar wrote:

This should probably document what happens to iterators to explain what the difference is compared to (a sequence of) erase.

https://github.com/llvm/llvm-project/pull/96762