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

[Utkarsh Saxena via cfe-commits]

================
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -Wdangling -Wdangling-field -Wreturn-stack-address -verify %s
+// RUN: %clang_cc1 --std=c++20 -fsyntax-only -Wdangling -Wdangling-field -Wreturn-stack-address -verify %s
----------------
usx95 wrote:

I think this should be fine. The analysis being tested is not specific to C++20. The use of concepts in the tests now requires C++20.

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