Yeah, a bunch of projects use Boehm (or their own GC, like the Lua VM). For large projects the extra size of including a GC implementation isn't so bad (but for

Yeah, a bunch of projects use Boehm (or their own GC, like the Lua VM). For large projects the extra size of including a GC implementation isn't so bad (but for small ones it can be). And it can be fairly fast. A problem is that you can't have GC cycles with the outside world, so you can't interact with the DOM in a normal way. In particular, your objects can't be automatically GC'd if they can be held on to by anything outside of the compiled linear memory. That's why emscripten's C++ <-> JS binding tool has a .destroy() method on each wrapped C++ object, as they need to be manually destroyed by the user. For local variables, they aren't scannable by themselves. You need to emit special inline code that writes them to linear memory. In C++, you can do this with an RAII class for a reference, for example.