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From: Manfred <noname@add.invalid>
Newsgroups: comp.lang.c
Subject: Re: missing gcc attribute "overwritable"
Date: Sun, 5 Jul 2020 20:23:22 +0200
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On 7/5/2020 10:34 AM, aotto1968zwei@gmail.com wrote:
> Am Freitag, 3. Juli 2020 09:38:02 UTC+2 schrieb aotto1...@gmail.com:
>> Am Freitag, 3. Juli 2020 04:33:06 UTC+2 schrieb donal...@gmail.com:
>>> On Thursday, July 2, 2020 at 1:56:33 PM UTC-4, aotto1...@gmail.com wrote:

<snip>

> After think about It, I come to the conclusion that it would be better to switch from:
>> __attribute__((overwritable))
> to the keyword "overwrite".
> 1. "overwrite" have to be applied to the OVERWRITING function and NOT to the
>     OVERWRITTEN function, this mean that OVERWRITABLE is the default.
> 2. This correspond with the c# definition of "override"
>     In the google translate the "overwrite" and the "override" are both the
>     same, the German word "überschreiben"
> 3. the "overwrite" will BREAK the c-syntax - NO compiler WITHOUT "overwrite"
>     feature will be able to translate this code
> 4. the new keyword "overwrite" implicit "static".

It appears you have changed the goal from manual adjustment of some 
generated library code to polymorphism - which is what the "override" 
keyword is about in C++ (and other languages including C#)
There are very good reasons for which polymorphism is explicitly part of 
the OO design[*], and it applies only to member functions, not global 
(or static) functions.
In fact, even in C polymorphism is typically implemented via function 
pointers inside some data structure (although C can have global function 
pointers as well).


Back to the original point, IIUC this feature was supposed to "ease" the 
work of the programmer when adjusting some generated code.
If so, you are envisioning an environment where you have some "bad" code 
generated by some tool, and "good" handwritten code that should replace 
the bad one - however, both the bad and the good code should survive in 
the product (otherwise there's no point in asking the compiler to 
replace anything).
/If/ this is what this is about, my opinion is that it is not going to 
make anyone's life easier.


[*] In fact when he first introduced virtual functions Stroustrup was 
criticized by some computer scientists at the time - the objection was 
that if the programmer does not know what some function does at the 
point of calling, then the software design is poor; the answer is that 
polymorphism does make sense in the context of object semantics.



> 
> Example:
<snip>