Re: technology discussion → does the world need a "new" C ?

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.