The original C compiler had no need for headers or function prototypes/forward declarations. Of course, it also was not a single-pass compiler: it had two (and a half) passes and generated assembly that would then be assembled by a two-pass assembler.

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fuzztester 4 days ago | parent [-]

Yes, function prototypes were introduced in the first ANSI version of C, IIRC, which came some years after the original C. The prototype feature was described in the second version of the classic K&R C book, The C Programming Language.

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pjmlp 4 days ago | parent [-]

Function prototypes came to ANSI/ISO C via the ongoing work on ISO C++.

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fuzztester 4 days ago | parent [-]

Doesn't matter where it came from - in the context of my previous comment.

I was talking w.r.t. the earlier version of C, and not in connection with C++.

	▲	pjmlp 4 days ago \| parent [-]
		It does from historical purposes, how the C standard came to be, what are the decisions that turned K&R C into C89.