diff --git a/src/ast/rewriter/arith_rewriter.cpp b/src/ast/rewriter/arith_rewriter.cpp
index 81385c2af..2b2087e3b 100644
--- a/src/ast/rewriter/arith_rewriter.cpp
+++ b/src/ast/rewriter/arith_rewriter.cpp
@@ -194,7 +194,7 @@ bool arith_rewriter::is_bound(expr * arg1, expr * arg2, op_kind kind, expr_ref &
         }
     }
     expr* t1, *t2;
-    bool is_int;
+    bool is_int = false;
     if (m_util.is_mod(arg2)) {
         std::swap(arg1, arg2);
         switch (kind) {