diff --git a/src/math/lp/nla_core.cpp b/src/math/lp/nla_core.cpp
index 00db7bc42..7950ffea1 100644
--- a/src/math/lp/nla_core.cpp
+++ b/src/math/lp/nla_core.cpp
@@ -1048,6 +1048,7 @@ new_lemma& new_lemma::operator|=(ineq const& ineq) {
 new_lemma::~new_lemma() {
     static int i = 0;
     (void)i;
+    (void)name;
     // code for checking lemma can be added here
     TRACE("nla_solver", tout << name << " " << (++i) << "\n" << *this; );
 }
diff --git a/src/model/value_factory.cpp b/src/model/value_factory.cpp
index 050e15c67..52fb4f7c0 100644
--- a/src/model/value_factory.cpp
+++ b/src/model/value_factory.cpp
@@ -82,7 +82,6 @@ expr * user_sort_factory::get_some_value(sort * s) {
         m_sort2value_set.find(s, set);
         SASSERT(set != 0);
         SASSERT(!set->m_values.empty());
-        unsigned nv = set->m_values.size();
         random_gen rand(m_manager.get_num_asts());
         unsigned n = 1;
         expr* result = nullptr;
diff --git a/src/smt/seq_regex.cpp b/src/smt/seq_regex.cpp
index 5df4cdc92..41a79ae9e 100644
--- a/src/smt/seq_regex.cpp
+++ b/src/smt/seq_regex.cpp
@@ -544,7 +544,6 @@ namespace smt {
         sort* elem_sort = nullptr, *seq_sort = nullptr;
         VERIFY(u().is_re(r, seq_sort));
         VERIFY(u().is_seq(seq_sort, elem_sort));
-        sort* domain[2] = { m.get_sort(n), a().mk_int() };
         return sk().mk("re.first", n, a().mk_int(r->get_id()), elem_sort);
     }
 }
diff --git a/src/smt/smt_induction.cpp b/src/smt/smt_induction.cpp
index c7562b608..dc90b1047 100644
--- a/src/smt/smt_induction.cpp
+++ b/src/smt/smt_induction.cpp
@@ -94,7 +94,9 @@ collect_induction_literals::collect_induction_literals(context& ctx, ast_manager
     m(m),
     vs(vs),
     m_literal_index(0)
-{}
+{
+    (void)vs;
+}
     
 literal_vector collect_induction_literals::operator()() {    
     literal_vector candidates = pre_select();
diff --git a/src/smt/theory_str.cpp b/src/smt/theory_str.cpp
index 32667f438..afb997370 100644
--- a/src/smt/theory_str.cpp
+++ b/src/smt/theory_str.cpp
@@ -8138,7 +8138,7 @@ namespace smt {
     // Returns true if this can be done in a valid way, placing the converted value in the argument.
     // Otherwise, returns false, if str is empty or contains non-digit characters.
     bool theory_str::string_integer_conversion_valid(zstring str, rational& converted) const {
-        bool valid = true;
+        // bool valid = true;
         converted = rational::zero();
         rational ten(10);
         if (str.length() == 0) {