javac, gcc, and clang all support some form of -std=<lang_level>, and ABI/source interop between code that uses different language versions. The post-gcc 2.95

javac, gcc, and clang all support some form of -std=<lang_level>, and ABI/source interop between code that uses different language versions. The post-gcc 2.95 C++ ABI breakage was pretty suck, though. [edit] And please don't misinterpret my criticism as intentional FUD. I work on $MAJOR_OS and am achingly tired of writing C, so I keep my eye on Rust as one possible salvation, once it's had time to mature. It's just a very hard sell when there's no ABI stability, we're talking about code that's expected to last for decades, etc.