Earlier quoted context omitted.
I thought you know Lisp? Now you are surprised that Lisp often looks up functions via symbols -> aka "late binding"? How can that be? That's one of the basic Lisp features. Next you can find out what optimizing compilers do to avoid it, where possible or where wanted.
At no point in time did I claim to know lisp well. I stated my familiarity at the outset. But what you all did was claim to know a lot about every other interpreted runtime without a grain of salt. >Next you can find out what optimizing compilers do to avoid it, where possible or where wanted. But compilers I am an expert in and what you're implying is impossible - either you have dynamic linkage, which means symbol…
You are incorrect; optimizations are possible in dynamic linking by making first references go through a slow path, which then patches some code thunk to make a direct call. This is limited only by the undesirability of making either the callling object or the called object a private, writable mapping. Because we want to keep both objects immutable, the call has to go into some privately mapped jump table. That table contains a thunk that can be rewritten to do a direct call to an absolute address. If we didn't care about sharing executables between address spaces we could patch the actual code in one object to jump directly to a resolved address in the other object. (mmap can do this: MAP_FILE plus MAP_PRIVATE: you map a file in a way that you can change the memory, but the changes appear only in your address space and not the file.)