Re: No warning at implicit removal of const. Was: relearning C: why does an in-place change to a char* segfault?

On 8/5/2024 4:03 AM, Ben Bacarisse wrote:

"Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:
 

On 8/4/2024 6:06 PM, Ben Bacarisse wrote:

"Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:
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On 8/2/2024 3:29 PM, Ben Bacarisse wrote:

"Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:
>

For some reason I had a sort of a habit wrt const pointers:
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(experimental code, no ads, raw text...)
https://pastebin.com/raw/f52a443b1
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________________________________
/* Interfaces
____________________________________________________________________*/
#include <stddef.h>
>
>
struct object_prv_vtable {
     int (*fp_destroy) (void* const);
};
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struct device_prv_vtable {
     int (*fp_read) (void* const, void*, size_t);
     int (*fp_write) (void* const, void const*, size_t);
};

Why?  It seems like an arbitrary choice to const qualify some pointer
types and some pointed-to types (but never both).

>
I just wanted to get the point across that the first parameter, aka, akin
to "this" in C++ is a const pointer. Shall not be modified in any way shape
or form. It is as it is, so to speak:
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void foo(struct foobar const* const self);
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constant pointer to a constant foobar, fair enough?

No.  If you intended a const pointer to const object why didn't you
write that?  My point was that the consts seems to be scattered about
without any apparent logic and you've not explained why.
>

;^)

Does the wink mean I should not take what you write seriously?  If so,
please ignore my question.

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The wink was meant to show my habit in basically a jestful sort of
way.

Your habit of what?

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To write the declaration with names and the const access I want, so:
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extern void (void const* const ptr);
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void (void const* const ptr)
{
    // ptr is a const pointer to a const void
}

 I don't think you are following what I'm, saying.  If you think there
might be some value in finding out, you could as a few questions.  I
won't say it again ;-)
 

I must be misunderstanding you. My habit in such code was to always make the "this" pointer wrt some of my "object" oriented code a const pointer. This was always the first parameter:
extern void foobar(void const* const ptr);
or
extern void foobar(void* const ptr);
Actually, I used the name of self for a while.
extern void foobar(void const* const self);
extern void foobar(void* const self);