diff --git a/tgt-vhdl/vhdl_syntax.cc b/tgt-vhdl/vhdl_syntax.cc
index f437a84f6..8047baa9c 100644
--- a/tgt-vhdl/vhdl_syntax.cc
+++ b/tgt-vhdl/vhdl_syntax.cc
@@ -662,6 +662,14 @@ void vhdl_const_bits::emit(std::ostream &of, int level) const
    of << (qualified_ ? "\")" : "\"");
 }
 
+vhdl_expr *vhdl_const_bit::cast(const vhdl_type *to)
+{
+   if (to->get_name() == VHDL_TYPE_INTEGER)
+      return new vhdl_const_int(bit_ == '1' ? 1 : 0);
+   else
+      return vhdl_expr::cast(to);
+}
+
 void vhdl_const_bit::emit(std::ostream &of, int level) const
 {
    of << "'" << vl_to_vhdl_bit(bit_) << "'";
diff --git a/tgt-vhdl/vhdl_syntax.hh b/tgt-vhdl/vhdl_syntax.hh
index 21a20510a..9f9fdcfcb 100644
--- a/tgt-vhdl/vhdl_syntax.hh
+++ b/tgt-vhdl/vhdl_syntax.hh
@@ -151,6 +151,7 @@ public:
    vhdl_const_bit(char bit)
       : vhdl_expr(vhdl_type::std_logic(), true), bit_(bit) {}
    void emit(std::ostream &of, int level) const;
+   vhdl_expr *cast(const vhdl_type *to);
 private:
    char bit_;
 };