Fix Issue 22997 - DMD crash: copy ctor can't call other ctor

[RazvanN7]

struct Forward{}

struct Foo{
    
    /// 1.
    this(scope ref typeof(this) rhs){
    	this(rhs, Forward.init);  //call ctor 2.
    }
    
    /// 2.
    this(scope ref typeof(this) rhs, Forward){}
    
    /// 3.
    this(scope typeof(this) rhs, int i, double d, string s){}
}

When calling the second constructor, the compiler needs to check all overloads to see the matches. Once it tries the 3rd constructor it tries to match its parameters and therefore it tries to copy construct rhs in the scope of the 3rd constructor. This leads to infinite recursion, because the new constructor call needs to check all of the constructors again. To break this cycle, I have added a new condition that checks whether the number of parameters non default parameters is greater than the number of arguments. If that is the case, then simply return no match and don't try to match args to params anymore. For that I needed to change a few tests, but I think that the error message is better anyway.

I am targeting master since I am going to do some follow up patches for the copy constructor that rely on this patch.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22997	regression	DMD crash: copy ctor can't call other ctor

⚠️⚠️⚠️ Warnings ⚠️⚠️⚠️

• Regression or critical bug fixes should always target the stable branch. Learn more about rebasing to stable or the D release process.

To target stable perform these two steps:

1. Rebase your branch to upstream/stable:

git rebase --onto upstream/stable upstream/master

2. Change the base branch of your PR to stable

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#13976"

[RazvanN7]

Does anyone know what I can do to make Windows 64bit happy?

src\dmd\mtype.d(4691): Deprecation: argument `nargs` for format specification `"%lu"` must be `uint`, not `const(ulong)`

Edit: I hammered it with a cast, following the example here https://github.com/dlang/dmd/blob/master/src/dmd/expressionsem.d#L4154

[dkorpel]

Since Foo has no pointers, scope is stripped in type semantic. Is it relevant to the bug?

[RazvanN7]

Nope, I simply copy-pasted the provided bug report. I can strip it manually.

[dkorpel]

Can you add a link to https://issues.dlang.org/show_bug.cgi?id=22997 in a comment? It's not self-explanatory why this branch is here.

[RazvanN7]

Sure.

[RazvanN7]

@dkorpel Done.

[thewilsonator]

This should go to stable.

[RazvanN7]

@thewilsonator I am intentionally targeting master since I need to do some follow-up changes that depend on this PR that have the potential to break user code.