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From: Ben Bacarisse <ben@bsb.me.uk>
Newsgroups: comp.lang.c
Subject: Re: technology discussion =?utf-8?Q?=E2=86=92?= does the world need
 a "new" C ?
Date: Wed, 10 Jul 2024 00:15:13 +0100
Organization: A noiseless patient Spider
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BGB <cr88192@gmail.com> writes:

> On 7/9/2024 12:22 PM, Ben Bacarisse wrote:
>> bart <bc@freeuk.com> writes:
>> 
>>> On 09/07/2024 16:58, Ben Bacarisse wrote:
>>>> bart <bc@freeuk.com> writes:
>>>>
>>>>> Arrays are passed by reference:
>>>>>
>>>>>     void F(int a[20]) {}
>>>>>
>>>>>     int main(void) {
>>>>>       int x[20];
>>>>>       F(x);
>>>>>     }
>>>> This is the sort of thing that bad tutors say to students so that they
>>>> never learn C properly.  All parameter passing in C is by value.  All of
>>>> it.  You just have to know (a) what the syntax means and (b) what values
>>>> get passed.
>>>
>>> The end result is that a parameter declared with value-array syntax is
>>> passed using a reference rather than by value.
>>>
>>> And it does so because the language says, not because the ABI requires
>>> it. A 2-byte array is also passed by reference.
>> An address value is passed by value.  C has only one parameter passing
>> mechanism.  You can spin it as much as you like, but C's parameter
>> passing is simple to understand, provided learner tune out voices like
>> yours.
>
> Though, in ABI specs, this would usually still be termed as "pass by
> reference"

I am not saying that Bart is alone in getting this wrong.  Any document
that that says that C have any parameter passing mechanism other than
pass by value is wrong.  But then I doubt any ABI spec says that since
an ABI is, almost by definition, not about the C language.

-- 
Ben.