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From: guy%gorodish@Sun.COM (Guy Harris)
Newsgroups: comp.unix.wizards
Subject: Re: have I found a bug in K&R?
Message-ID: <31164@sun.uucp>
Date: Sun, 18-Oct-87 00:16:01 EDT
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Posted: Sun Oct 18 00:16:01 1987
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> This applies whether they are declared as formal parameters or as
> external array declarations. I often declare functions like
> 	fn(a,b)
> 	char *a;
> 	char b[];
> in order to *prevent* myself from changing b during the function.
> It eliminates some coding errors by making the compiler do some
> extra checking for me.

Umm, guess again.  K&R says, in 10.1 "External function definitions":

	...Also, since a reference to an array in any context (in particular as
	an actual parameter) is taken to mean a pointer to the first element of
	the array, declarations of formal parameters declared ``array of ...''
	are adjusted to read ``pointer to ...'''.

Which means that the compiler will treat the declarations of "a" *and* "b" as
declarations of pointers.  Furthermore, PCC, at least, works this way, so most
PCC-based compilers aren't doing any extra checking for you.
	Guy Harris
	{ihnp4, decvax, seismo, decwrl, ...}!sun!guy
	guy@sun.com