https://issues.dlang.org/show_bug.cgi?id=23926

dave287091@gmail.com changed:

           What    |Removed                     |Added
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           Keywords|                            |ImportC

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https://issues.dlang.org/show_bug.cgi?id=23926

--- Comment #1 from dave287091@gmail.com ---
Thinking more about this, C doesn’t have transitive const so maybe this is actually correct. Maybe D needs head const to properly express C const.

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https://issues.dlang.org/show_bug.cgi?id=23926

--- Comment #2 from dave287091@gmail.com ---
(In reply to dave287091 from comment #1)
> Thinking more about this, C doesn’t have transitive const so maybe this is actually correct. Maybe D needs head const to properly express C const.

The error message could be improved though.

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https://issues.dlang.org/show_bug.cgi?id=23926

Walter Bright <bugzilla@digitalmars.com> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
                 CC|                            |bugzilla@digitalmars.com
         Resolution|---                         |LATER

--- Comment #3 from Walter Bright <bugzilla@digitalmars.com> ---
You're right, it's about the non-transitivity of C const. D's choices are:

1. compile correct C code, and also compile some incorrect C code

2. not compile some correct C code, not compile incorrect C code

3. implement non-transitive const in D

(1) is the most pragmatic choice. Maybe eventually we can do (3), but it's a
low priority. Note that any hand-translated C code to D has the same issue.

Improving the error message also would be rather clumsy. I wish I had better news on that.

BTW, `const struct Foo*` in C looks like const(Foo)* in D, while `const Foo*`
in D is actually `const(Foo*)`.

I'm going to resolve this as "LATER".

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https://issues.dlang.org/show_bug.cgi?id=23926

Lance Bachmeier <lance@lancebachmeier.com> changed:

           What    |Removed                     |Added
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                 CC|                            |lance@lancebachmeier.com

--- Comment #4 from Lance Bachmeier <lance@lancebachmeier.com> ---
Can this be resolved by having ImportC generate a D overload? If const struct Foo* is rewritten to Foo*, it should. This is a solution for this particular example:

struct Foo;
void foo(Foo* x) {}
// ImportC generates this function when encountering const struct Foo*
void foo(const(Foo)* x) {
        foo(cast(Foo*) x);
}
void bar(const Foo* x) {
    foo(x);
}

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