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From: Michael S <already5chosen@yahoo.com>
Newsgroups: comp.lang.c
Subject: Re: Two questions on arrays with size defined by variables
Date: Sun, 9 Feb 2025 19:57:11 +0200
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On Sun, 9 Feb 2025 18:18:04 +0100
Janis Papanagnou <janis_papanagnou+ng@hotmail.com> wrote:

> On 09.02.2025 11:39, Michael S wrote:
> > On Sun, 9 Feb 2025 10:54:36 +0100
> > Janis Papanagnou <janis_papanagnou+ng@hotmail.com> wrote:
> > [...]
> > 
> > There is another problem in your code - it assigns string literal to
> > non-const char*. It is legal, as far as 'C' Standard is concerned,
> > but makes very little practical sense, because any attempt to
> > assign to string literal through resulting pointer is UB. And not
> > just a theoretical UB, but a real-world UB.  
> 
> This comment specifically draw my attention and made me nervous.
> 
> You know, I'm rarely programming in plain "C", and while in C++
> I generally try to program in "const-correct" form 

Which, I suppose, is not easy.

> I never make
> use of 'const' in "C". - Unless the compiler complains about it,
> but I don't recall it (ever?) did.
> 
> In my test application I actually never assign string literals
> or strings to any other string object (modulo the buffer that I
> filled with a 'fgets'). I operate solely with pointers to 'argv'
> elements and to the 'char buf[]' buffer data.
> 
> Do you see any issue with that?
> 
> Janis
> 

I see no issues.

Generally, due to absence of user-defined polymorphism, C does not have
the type of ugly surprises with constness that make life of C++
programmers miserable. Still, behavior of string literals can be
surprising.
I would guess that if it was feasible to make a breaking changes, C89
would define type of string literals as 'const char*' rather than
'char*'. But breaking changes were not feasible.