| > I don't know realistically what Obj C uses in the osx cpu architecture but I'm almost certain it's not going to be as simple as just retargeting your compiler... Objective C is in mainline GCC. You retarget your compiler and port the runtime. As far as I know, any target with GCC support can run Objective C, given a runtime. The important parts of the runtime require kilobytes, not megabytes, of space. Remember that Objective C was originally a very thin layer on top of C. You take all the [method calls] and replace them with calls to objc_msgSend(). The overhead is fairly small— your object instances need the “isa” pointer, which is basically just a pointer to a vtable. The objc_msgSend() function reads the vtable and forwards method calls to the correct implementation. My experience is that Objective C binaries typically have a much smaller footprint than C++ binaries. That’s obviously not some kind of rule, but it reflects idiomatic usage of Objective C. In C++ you'd use a std::vector<T> which is a templated class, which gets instantiated for every different T you use in your program. In Objective C, you’d use NSArray, which is monomorphic. This all should be completely unsurprising—since Objective C first appeared in the 1980s, it’s no surprise that it doesn’t need much memory. |