[clang] [clang] Add C++26 diagnostics to compatibility diagnosic groups (PR #97806)

[Vlad Serebrennikov via cfe-commits]

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@@ -384,39 +386,47 @@ def CXX11Compat : DiagGroup<"c++11-compat",
                              CXXPre14Compat,
                              CXXPre17Compat,
                              CXXPre20Compat,
-                             CXXPre23Compat]>;
+                             CXXPre23Compat,
+                             CXXPre26Compat]>;
 def : DiagGroup<"c++0x-compat", [CXX11Compat]>;
 def CXX11CompatPedantic : DiagGroup<"c++11-compat-pedantic",
                                     [CXX11Compat,
                                      CXXPre14CompatPedantic,
                                      CXXPre17CompatPedantic,
                                      CXXPre20CompatPedantic,
-                                     CXXPre23CompatPedantic]>;
+                                     CXXPre23CompatPedantic,
+                                     CXXPre26CompatPedantic]>;
 
 def CXX14Compat : DiagGroup<"c++14-compat", [CXXPre17Compat,
                                              CXXPre20Compat,
-                                             CXXPre23Compat]>;
+                                             CXXPre23Compat,
+                                             CXXPre26Compat]>;
 def CXX14CompatPedantic : DiagGroup<"c++14-compat-pedantic",
                                     [CXX14Compat,
                                      CXXPre17CompatPedantic,
                                      CXXPre20CompatPedantic,
-                                     CXXPre23CompatPedantic]>;
+                                     CXXPre23CompatPedantic,
+                                     CXXPre26CompatPedantic]>;
 
 def CXX17Compat : DiagGroup<"c++17-compat", [DeprecatedRegister,
                                              DeprecatedIncrementBool,
                                              CXX17CompatMangling,
                                              CXXPre20Compat,
-                                             CXXPre23Compat]>;
+                                             CXXPre23Compat,
+                                             CXXPre26Compat]>;
 def CXX17CompatPedantic : DiagGroup<"c++17-compat-pedantic",
                                     [CXX17Compat,
                                      CXXPre20CompatPedantic,
-                                     CXXPre23CompatPedantic]>;
+                                     CXXPre23CompatPedantic,
+                                     CXXPre26CompatPedantic]>;
 def : DiagGroup<"c++1z-compat", [CXX17Compat]>;
 
-def CXX20Compat : DiagGroup<"c++20-compat", [CXXPre23Compat]>;
+def CXX20Compat : DiagGroup<"c++20-compat", [CXXPre23Compat,
+                                             CXXPre26Compat]>;
 def CXX20CompatPedantic : DiagGroup<"c++20-compat-pedantic",
                                     [CXX20Compat,
-                                     CXXPre23CompatPedantic]>;
+                                     CXXPre23CompatPedantic,
+                                     CXXPre26CompatPedantic]>;
----------------
Endilll wrote:

My initial though was to not add a flag that doesn't do anything, but I added it as you requested.

https://github.com/llvm/llvm-project/pull/97806