{motive : Lean.Compiler.LCNF.AuxDeclCacheKey → Sort u} →
  (t : Lean.Compiler.LCNF.AuxDeclCacheKey) →
    ((pu : Lean.Compiler.LCNF.Purity) → (decl : Lean.Compiler.LCNF.Decl pu) → motive { pu := pu, decl := decl }) →
      motive t