[clang] [clang] Implement lifetime analysis for lifetime_capture_by(X) (PR #115921)

[Boaz Brickner via cfe-commits]

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@@ -3925,13 +3925,20 @@ def LifetimeCaptureByDocs : Documentation {
 parameter or implicit object parameter indicates that that objects that are referred to
 by that parameter may also be referred to by the capturing entity ``X``.
 
-By default, a reference is considered to refer to its referenced object, a
-pointer is considered to refer to its pointee, a ``std::initializer_list<T>``
-is considered to refer to its underlying array, and aggregates (arrays and
-simple ``struct``\s) are considered to refer to all objects that their
-transitive subobjects refer to.
+By default:
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bricknerb wrote:

Below is a list of types and what they're considered to refer to, but it's not very clear for what purpose they're considered to refer to.

First, I think it's worth clarifying whether you're talking about the types of the parameter or the type of X (the capturing entity).
Second, what is the purpose of this consideration?

https://github.com/llvm/llvm-project/pull/115921