The 5.16 does come with stdio.h
it didn't when i tried it, otherwise i wouldn't post it
now that I look the original tar, that's true: the std* headers are "generated" when you compile, because in the new version they are generated when you make the rule
include/iosenum.h, to match the compiler and platform configuration used (so it will work with compilers other than VC, like MinGW).
so then, if you want only the interpreter and don't care mixing interpreted code with compiled code, or don't care for compiling cint, do what tiwag suggests above.
otherwise, (you want to use makecint, want to compile cint, or want the latest ver.), do what I said above.