fix #4082

Signed-off-by: Nikolaj Bjorner <[email protected]>

Author: NikolajBjorner

src/smt/asserted_formulas.cpp

@@ -137,6 +137,8 @@ void asserted_formulas::set_eliminate_and(bool flag) {
     m_params.set_bool("expand_select_store", true);
     //m_params.set_bool("expand_nested_stores", true);
     m_params.set_bool("bv_sort_ac", true);
+    // seq theory solver keeps terms in normal form and has to interact with side-effect of rewriting
+    // m_params.set_bool("coalesce_chars", m_smt_params.m_string_solver != symbol("seq"));
     m_params.set_bool("som", true);
     m_rewriter.updt_params(m_params);
     flush_cache();

src/smt/theory_seq.cpp

@@ -1049,6 +1049,9 @@ bool theory_seq::add_solution(expr* l, expr* r, dependency* deps)  {
     }
     m_new_solution = true;
     m_rep.update(l, r, deps);
+    expr_ref sl(l, m);
+    m_rewrite(sl);
+    m_rep.update(sl, r, deps);
     enode* n1 = ensure_enode(l);
     enode* n2 = ensure_enode(r);    
     TRACE("seq", tout << mk_bounded_pp(l, m, 2) << " ==> " << mk_bounded_pp(r, m, 2) << "\n"; display_deps(tout, deps);