[Issue 22540] Instantiation modifies dependant type of value / alias template parameters

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=22540

Dlang Bot <dlang-bot at dlang.rocks> changed:

           What    |Removed                     |Added
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           Keywords|                            |pull

--- Comment #1 from Dlang Bot <dlang-bot at dlang.rocks> ---
@MoonlightSentinel created dlang/dmd pull request #13352 "Fix 22540 - Copy
parameter types / defaults of dependant template..." fixing this issue:

- Fix 22540 - Copy parameter types / defaults of dependant template...

  ... value / alias parameters.

  The introduced copies ensure that the initialized parameters of the
  instantiation do not share objects with the template declaration.

  Previously, sharing could occur in the following scenarios:

  - type parameter appears inside of value type, e.g. `foo(T, T* val)`
    Later semantic resolves `T` to the concrete type and hence changes
    the type of `val` in the template declaration.
  - alias parameter default value isn't copied and manifested according to
    the first template instance.

https://github.com/dlang/dmd/pull/13352

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