diff --git a/src/iss/arch/riscv_hart_common.h b/src/iss/arch/riscv_hart_common.h
index da5fe29..e1523a6 100644
--- a/src/iss/arch/riscv_hart_common.h
+++ b/src/iss/arch/riscv_hart_common.h
@@ -884,8 +884,7 @@ protected:
 
     instrumentation_if* get_instrumentation_if() override { return &instr_if; };
 
-    using csr_type = util::sparse_array<typename traits<BASE>::reg_t, 1ULL << 12, 12>;
-    using csr_page_type = typename csr_type::page_type;
+    using csr_type = std::array<typename traits<BASE>::reg_t, 1ULL << 12>;
     csr_type csr;
 
     std::unordered_map<unsigned, rd_csr_f> csr_rd_cb;
diff --git a/src/iss/debugger/riscv_target_adapter.h b/src/iss/debugger/riscv_target_adapter.h
index a99c612..951597c 100644
--- a/src/iss/debugger/riscv_target_adapter.h
+++ b/src/iss/debugger/riscv_target_adapter.h
@@ -39,7 +39,6 @@
 #include <iss/iss.h>
 
 #include <array>
-#include <memory>
 #ifndef FMT_HEADER_ONLY
 #define FMT_HEADER_ONLY
 #endif