Automerge: fix abi

Author: cor3ntin

clang/include/clang/Sema/Sema.h

@@ -10671,6 +10671,10 @@ class Sema final : public SemaBase {
                            SourceLocation EndLoc);
   void ActOnForEachDeclStmt(DeclGroupPtrTy Decl);
 
+
+  // Unused, kept in Clang 20 for ABI stability.
+  void DiagnoseDiscardedExprMarkedNodiscard(const Expr *E) {};
+
   /// DiagnoseUnusedExprResult - If the statement passed in is an expression
   /// whose result is unused, warn.
   void DiagnoseUnusedExprResult(const Stmt *S, unsigned DiagID);