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

[Haojian Wu via cfe-commits]

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@@ -793,3 +806,202 @@ void test13() {
 }
 
 } // namespace GH100526
+
+namespace lifetime_capture_by {
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hokein wrote:

I think it is probably worth having a separated test for this capture_by attribute. We could move the std types to a common header to reuse the code.

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