[clang] Sema: suppress deprecated field warnings in implicit special-member functions Fixes: https://github.com/llvm/llvm-project/issues/147293 (PR #147400)

[Yanzuo Liu via cfe-commits]

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@@ -547,6 +547,20 @@ static void DoEmitAvailabilityWarning(Sema &S, AvailabilityResult K,
     return;
   }
   case AR_Deprecated:
+    // Suppress -Wdeprecated-declarations in purely implicit special-member functions.
+    if (const FunctionDecl *FD = S.getCurFunctionDecl()) {
+      // Only proceed if this is an implicit, defaulted member function:
+      if (auto *MD = dyn_cast_if_present<CXXMethodDecl>(FD);
+          MD && MD->isImplicit() && MD->isDefaulted()) {
+        // Match any special-member kind:
+        if (isa<CXXConstructorDecl>(MD) ||
+            isa<CXXDestructorDecl>(MD) ||
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zwuis wrote:

`isa<Decl1, Decl2>(MD)`

https://github.com/llvm/llvm-project/pull/147400