[clang] [C++26][clang] Implement P2795R5 'Erroneous behaviour for uninitialized reads' (PR #177614)

[Vlad Serebrennikov via cfe-commits]

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@@ -4,7 +4,7 @@
 // RUN: %clang_cc1 -std=c++17 %s -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify=expected,since-cxx11
 // RUN: %clang_cc1 -std=c++20 %s -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify=expected,since-cxx11
 // RUN: %clang_cc1 -std=c++23 %s -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify=expected,since-cxx11
-// RUN: %clang_cc1 -std=c++2c %s -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify=expected,since-cxx11
+// RUN: %clang_cc1 -std=c++26 %s -fexceptions -fcxx-exceptions -pedantic-errors -verify-directives -verify=expected,since-cxx11
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Endilll wrote:

Why is this necessary for this PR?

https://github.com/llvm/llvm-project/pull/177614