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Re: Function Prototypes: Necessary or just good practice?

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On 2012-02-14, /dev/phaeton <blahbleh666@no_more_spam.hotmail.com> wrote:
> In K&R2, function definitions in a program were preceded by a function 
> prototype, i.e.:

It's good practice to declare functions before calling them.
Calling undeclared functions is a deprecated language feature.

However, there is often no need for prototypes within one translation unit,
because you can organize the code so that each function is defined prior to any
calls to the function. A function definition serves as a prototype declaration.

This arrangement is impossible when you have mutual recursion among
two or more functions. Some of them have to be prototyped.

> However, I've noticed that if I omit the function prototype, the program 
> compiles (with gcc 4.6.x at least) and runs just fine.  

With what warning options?

How about with -Wall and -W?

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Function Prototypes: Necessary or just good practice? /dev/phaeton <blahbleh666@no_more_spam.hotmail.com> - 2012-02-13 23:05 -0600
  Re: Function Prototypes: Necessary or just good practice? Johann Klammer <klammerj@NOSPAM.a1.net> - 2012-02-14 07:31 +0100
    Re: Function Prototypes: Necessary or just good practice? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-14 13:14 +0000
      Re: Function Prototypes: Necessary or just good practice? Ralf Damaschke <rwspam@gmx.de> - 2012-02-14 16:20 +0000
      Re: Function Prototypes: Necessary or just good practice? Peter Nilsson <airia@acay.com.au> - 2012-02-14 13:47 -0800
        Re: Function Prototypes: Necessary or just good practice? James Kuyper <jameskuyper@verizon.net> - 2012-02-14 17:01 -0500
          Re: Function Prototypes: Necessary or just good practice? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-14 22:35 +0000
            Re: Function Prototypes: Necessary or just good practice? James Kuyper <jameskuyper@verizon.net> - 2012-02-14 17:51 -0500
              Re: Function Prototypes: Necessary or just good practice? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-15 00:06 +0000
          Re: Function Prototypes: Necessary or just good practice? Peter Nilsson <airia@acay.com.au> - 2012-02-14 20:27 -0800
            Re: Function Prototypes: Necessary or just good practice? Keith Thompson <kst-u@mib.org> - 2012-02-14 22:24 -0800
  Re: Function Prototypes: Necessary or just good practice? Stephen Sprunk <stephen@sprunk.org> - 2012-02-14 01:18 -0600
  Re: Function Prototypes: Necessary or just good practice? Philip Lantz <prl@canterey.us> - 2012-02-14 00:05 -0800
  Re: Function Prototypes: Necessary or just good practice? Kaz Kylheku <kaz@kylheku.com> - 2012-02-14 09:09 +0000
    Re: Function Prototypes: Necessary or just good practice? /dev/phaeton <blahbleh666@no_more_spam.hotmail.com> - 2012-02-14 23:51 -0600
      Re: Function Prototypes: Necessary or just good practice? Kaz Kylheku <kaz@kylheku.com> - 2012-02-15 06:36 +0000
      Re: Function Prototypes: Necessary or just good practice? James Kuyper <jameskuyper@verizon.net> - 2012-02-15 08:31 -0500

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