ASAN is throwing a container-overflow because we are accessing a region in the vector that is valid but does not have an element. We can avoid this by using resize instead of reserve. See the documentation for container-overflow for more details: https://github.com/google/sanitizers/wiki/AddressSanitizerContainerOverflow#:~:text=One%20kind%20of%20bugs%20that%20AddressSanitizer%20can%20find,outside%20of%20the%20current%20container%20bounds.%20Simplest%20example%3A Bug: webrtc:13541 Change-Id: Id11def90ef8c2cfec9c20f38384547ce6c37b980 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/244861 Reviewed-by: Alexander Cooper <alcooper@chromium.org> Commit-Queue: Austin Orion <auorion@microsoft.com> Cr-Commit-Position: refs/heads/main@{#35654}