[llvm] [DebugInfo] Add an specification_of attribute to LLVM DebugInfo (PR #115362)

[Adrian Prantl via llvm-commits]

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@@ -488,6 +488,9 @@ namespace llvm {
     /// \param Elements     Struct elements.
     /// \param RunTimeLang  Optional parameter, Objective-C runtime version.
     /// \param UniqueIdentifier A unique identifier for the struct.
+    /// \param SpecificationOf The type that this type completes (is a
+    /// specification of). For example, this could be a templated type whose
+    /// template parameters have been substituted in.
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adrian-prantl wrote:

If you are using the word `template` you're confusing an image of C++, but, this isn't actually used for C++ at the moment. So maybe it's better to explain this in terms of what this is used for in the Swift frontend?

https://github.com/llvm/llvm-project/pull/115362