in reply to
Re^4: Perl 5 interpreter
in thread Perl 5 interpreter
If "by choice" you mean "the C compiler that my OS vendor uses", I guess too many, especially for OSes that you pay real money for :-)
I think there are some macros that you can't conveniently elide, like dTHX, which expands to "the current thread context" if Perl is compiled with iThreads and "nothing" if threads are not compiled (but you know that). I'm not sure whether having inlined functions is much better, structurally, than having the macros.