RGSep is a program logic for reasoning about the correctness of concurrent programs
that combines rely-guarantee reasoning and separation logic.
Although RGSep was initially developed for sequential consistency,
we show that it is also sound under the much weaker release-acquire (RA) consistency model,
which is a well-behaved subset of the C++11 concurrency model.
Our result provides a simpler way to reason about RA programs
than the state-of-the-art program logics that support weak memory consistency models.