Ocaml compiled. You seem to be used to interpreted languages, where the runtime system has access to the complete source code of the program. Using a compiled program, the runtime system does not have access to a lot of information. For example, variable names disappear during compilation, and nothing will track the arguments passed to each function, unless it is necessary for the program to run normally (this will require a lot of overhead).
( -g ), , . , . , . OCAMLRUNPARAM , b .
ocamlc -g -o foo foo.ml
export OCAMLRUNPARAM=b
./foo
, .