[clang] [Clang] update reasoned delete diagnostic kind to use Extension, making it pedantic only (PR #114713)

[Aaron Ballman via cfe-commits]

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@@ -1,7 +1,17 @@
-// RUN: %clang_cc1 -std=c++23 -fsyntax-only -verify=expected,pre26 -pedantic %s
+// RUN: %clang_cc1 -std=c++17 -fsyntax-only -verify=expected -DTEST_NON_PEDANTIC %s
+// RUN: %clang_cc1 -std=c++17 -fsyntax-only -verify=expected,pre26 -pedantic %s
 // RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify=expected,compat -Wpre-c++26-compat %s
 // RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify %s
 
+#ifdef DTEST_NON_PEDANTIC
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AaronBallman wrote:

It would be better to avoid the conditional logic and instead use `-verify` prefixes alone.

https://github.com/llvm/llvm-project/pull/114713