[clang] [clang][Sema] Deprecate `global`/`unknown` in `lifetime_capture_by` (PR #196635)

[Aaron Ballman via cfe-commits]

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@@ -4426,6 +4450,17 @@ LifetimeCaptureByAttr *Sema::ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
     }
     assert(AL.isArgIdent(I));
     IdentifierLoc *IdLoc = AL.getArgAsIdent(I);
+    StringRef Name = IdLoc->getIdentifierInfo()->getName();
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AaronBallman wrote:

You can use `IdentifierInfo::isStr()` instead of getting the name as a string, then pass the `IdentifierInfo *` into the call to `Diag` and it will be quoted properly in the diagnostic text.

https://github.com/llvm/llvm-project/pull/196635