Hi, I've run into issues with code using Bimap and GCC optimizations. The description has been submitted both as a bug report to GCC (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115767) and as an issue in Boost Bimap (https://github.com/boostorg/bimap/issues/43). While trying to reduce the Bimap code to find a minimal example, I've found what looks like a proper bug in Bimap and have created a pull request (https://github.com/boostorg/bimap/pull/45). It's now been two weeks and the PR is still awaiting approval, so I thought maybe I better write about it here as well. I suspect the issues might come from both a bug in GCC optimizations and from Bimap, because they seem to be gone when I compile with the latest GCC (which received some optimization-related patches lately) and the patched Bimap, both on aarch64 and x86_64, but I can't tell for sure. Cheers, Ignacy