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| From | Bartc <bc@freeuk.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Do variables need to be initialized? |
| Date | 2015-06-06 19:09 +0100 |
| Organization | A noiseless patient Spider |
| Message-ID | <mkvcv9$jji$1@dont-email.me> (permalink) |
| References | (2 earlier) <3572098e-4afe-4626-afdc-e6d67ce2388d@googlegroups.com> <6711371c-5e7c-4af2-a629-6d701827a2a5@googlegroups.com> <mkshk3$9jt$1@dont-email.me> <mkslqf$srg$1@dont-email.me> <mkv615$n3r$1@dont-email.me> |
On 06/06/2015 17:11, Stephen Sprunk wrote:
> On 05-Jun-15 12:22, Bartc wrote:
>> On 05/06/2015 17:10, Stephen Sprunk wrote:
>>> On 04-Jun-15 12:17, David Kleinecke wrote:
>>>> One reason it was silly is that mixing changes nothing significant.
>>>
>>> AIUI, early compilers worked line-by-line, and they needed all the
>>> declarations in one place so they could set up the stack frame before
>>> translating the following statements into code.
>>
>> That seems to be still the case, in that functions need to be declared
>> before use (or at least, will cause problems if they're not).
>
> That's because you need to know the argument and return types to
> properly generate the code to call the function.
That can't have been the actual reason for decades. It's unlikely that
final code will be generated for a function before the rest of the file
has been scanned.
But C compilers still seem happy to generate code for a non-existent
function that they've not had sight of at all; gcc compiles this with no
problem:
int main(void) {
anyfunction(10,20,30.9);
}
It just seems incredibly odd that it can process calls for functions it
knows nothing about, and may not actually exist, or exist but with a
totally different signature that will probably cause the program to
crash, but it can't do so for an actual function that is fully defined
20 lines further on in the file!
--
Bartc
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Do variables need to be initialized? fl <rxjwg98@gmail.com> - 2015-06-01 16:48 -0700
Re: Do variables need to be initialized? Richard Heathfield <rjh@cpax.org.uk> - 2015-06-02 00:55 +0100
Re: Do variables need to be initialized? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-06-01 18:22 -0600
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-06-02 08:05 -0700
Re: Do variables need to be initialized? Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 08:07 -0700
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-07-11 16:47 -0700
Re: Do variables need to be initialized? Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-15 07:42 -0700
Re: Do variables need to be initialized? Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 08:03 -0700
Re: Do variables need to be initialized? David Brown <david.brown@hesbynett.no> - 2015-06-02 09:15 +0200
Re: Do variables need to be initialized? Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 08:09 -0700
Re: Do variables need to be initialized? David Kleinecke <dkleinecke@gmail.com> - 2015-06-03 09:30 -0700
Re: Do variables need to be initialized? gwowen <gwowen@gmail.com> - 2015-06-03 09:41 -0700
Re: Do variables need to be initialized? David Kleinecke <dkleinecke@gmail.com> - 2015-06-04 10:17 -0700
Re: Do variables need to be initialized? Stephen Sprunk <stephen@sprunk.org> - 2015-06-05 11:10 -0500
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-05 18:22 +0100
Re: Do variables need to be initialized? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-06-05 20:54 -0600
Re: Do variables need to be initialized? Ian Collins <ian-news@hotmail.com> - 2015-06-06 15:49 +1200
Re: Do variables need to be initialized? Dr Nick <nospam-4@temporary-address.org.uk> - 2015-06-06 08:42 +0100
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-06-06 13:11 -0700
Re: Do variables need to be initialized? Dr Nick <nospam-4@temporary-address.org.uk> - 2015-06-07 16:58 +0100
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-06 11:01 +0100
Re: Do variables need to be initialized? Ian Collins <ian-news@hotmail.com> - 2015-06-07 09:07 +1200
Re: Do variables need to be initialized? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-06-06 15:06 -0600
Re: Do variables need to be initialized? gwowen <gwowen@gmail.com> - 2015-06-08 05:39 -0700
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-08 14:10 +0100
Re: Do variables need to be initialized? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-08 14:21 +0100
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-08 14:34 +0100
Re: Do variables need to be initialized? David Brown <david.brown@hesbynett.no> - 2015-06-08 16:51 +0200
Re: Do variables need to be initialized? Richard Heathfield <rjh@cpax.org.uk> - 2015-06-08 16:15 +0100
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-08 17:31 +0100
Re: Do variables need to be initialized? Ian Collins <ian-news@hotmail.com> - 2015-06-09 08:06 +1200
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-08 22:58 +0100
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-06-08 08:27 -0700
Re: Do variables need to be initialized? gwowen <gwowen@gmail.com> - 2015-06-08 08:01 -0700
Re: Do variables need to be initialized? Stephen Sprunk <stephen@sprunk.org> - 2015-06-06 11:11 -0500
Re: Do variables need to be initialized? Bartc <bc@freeuk.com> - 2015-06-06 19:09 +0100
Re: Do variables need to be initialized? Robert Wessel <robertwessel2@yahoo.com> - 2015-06-06 13:57 -0500
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-06-06 13:52 -0700
Re: Do variables need to be initialized? James Kuyper <jameskuyper@verizon.net> - 2015-06-06 20:57 -0400
Re: Do variables need to be initialized? Stephen Sprunk <stephen@sprunk.org> - 2015-06-10 14:33 -0500
Re: Do variables need to be initialized? Keith Thompson <kst-u@mib.org> - 2015-06-05 10:56 -0700
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