Re: question about linker

On 28/11/2024 22:38, Keith Thompson wrote:

Bart <bc@freeuk.com> writes:

On 28/11/2024 19:58, Keith Thompson wrote:

Bart <bc@freeuk.com> writes:
[...]

I think 'const' is confusing for similar reasons that VLAs can be both
confusing and awkward to implement.
>
That's because both really apply to /types/, not directly to variables.

Sure.  For example, given
      const int n = 42;
n is of type `const int`, and &n is of type `consts int*`.  Of course
that implies that n itself is const.

>
But that is a separate thing. Suppose T was an alias for 'const int'. Then:
>
   T x;           // defines a readonly variable (which probably needs
                  // initialising)
   T* y;          // defines a variable pointer
>
'const' is out of the picture.

 You say T is an alias (what, a macro?) for 'const int', you show code
using T, and then you say "'const' is out of the picture".  If you have
a point, it escapes me.

Well, can you see 'const' in my example? You can't tell x is readonly by only looking at this.

Yes, and you seem determines to make it easier to get mixed up.

C doesn't require any help from me for confusing features. The OP said it was confusing and I tried to point out why it might be.
Obviously you as C expert will never be confused. But there are lots of less expert users of the language.
I've just several minutes trying to figure why all these assignments are invalid:
     typedef int* T;
     int  const x;
     T    const y;
     int* const z;
     x=0;
     y=0;
     z=0;
because I thought would behave differently, with 'const' being the opposite side of '*' to the base-type.
I forgot that here it would be the right-most 'const' that controls storage attributes of 'z'.
You will of course say that I'm the only person in the world who could make that mistake.