[Issue 23681] Generated copy constructors failing to generate

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23681

RazvanN <razvan.nitu1305 at gmail.com> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
                 CC|                            |razvan.nitu1305 at gmail.com
         Resolution|---                         |DUPLICATE

--- Comment #1 from RazvanN <razvan.nitu1305 at gmail.com> ---
When the copy constructor for Depender is generated it looks like:

this(ref inout Depender src) inout
{
    this.dependency = dependency;
}

However, this.dependency = dependency is rewritten to
this.dependency.copyCtor(dependency); which cannot be called because it is
mutable and we are using inout objects. Therefore the cpctor is marked as
disable.

The destructor of Dependency causes the compiler to generate an opAssign with
the signature "ref Dependency opAssign(Dependency src)". The existence of this
assignment operator causes Depender (which contains a Dependency) to also
define an opAssign which receives the argument by value. That is where the
generated (and disabled) copy constructor is called.

This is another effect of what I described here:
https://issues.dlang.org/show_bug.cgi?id=20876#c4 .

Fixing 20876 to correctly generate more accurate copy constructors will also
fix this.

Another approach would be to stop generating assignment operators based on copy
constructors and destructors.

*** This issue has been marked as a duplicate of issue 20876 ***

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