diff -r 8f0b2daa7eaa -r d93ead9ac6df src/HOL/TLA/Memory/MemoryImplementation.thy
--- a/src/HOL/TLA/Memory/MemoryImplementation.thy	Thu Jun 12 08:03:05 2025 +0200
+++ b/src/HOL/TLA/Memory/MemoryImplementation.thy	Thu Jun 12 12:44:47 2025 +0200
@@ -231,7 +231,7 @@
     else K no_tac);
 \<close>
 
-setup \<open>map_theory_simpset (fn ctxt => ctxt addSSolver fast_solver)\<close>
+setup \<open>map_theory_simpset (fn ctxt => ctxt |> Simplifier.add_safe_solver fast_solver)\<close>
 
 ML \<open>val temp_elim = make_elim oo temp_use\<close>