byte-compile-discard is a compiled Lisp function in `bytecomp.el'.

(byte-compile-discard &optional NUM PRESERVE-TOS)

Output byte codes to discard the NUM entries at the top of the stack.
NUM defaults to 1.
If PRESERVE-TOS is non-nil, preserve the top-of-stack value, as if it were
popped before discarding the num values, and then pushed back again after