diff --git a/src/border_agent/border_agent.cpp b/src/border_agent/border_agent.cpp
index f8a1e0fc218..4b22fd0dd22 100644
--- a/src/border_agent/border_agent.cpp
+++ b/src/border_agent/border_agent.cpp
@@ -69,9 +69,11 @@
 
 namespace otbr {
 
-static const char    kBorderAgentServiceType[]      = "_meshcop._udp";   ///< Border agent service type of mDNS
-static const char    kBorderAgentEpskcServiceType[] = "_meshcop-e._udp"; ///< Border agent ePSKc service
-static constexpr int kBorderAgentServiceDummyPort   = 49152;
+static const char kBorderAgentServiceType[] = "_meshcop._udp"; ///< Border agent service type of mDNS
+#if OTBR_ENABLE_EPSKC
+static const char kBorderAgentEpskcServiceType[] = "_meshcop-e._udp"; ///< Border agent ePSKc service
+#endif
+static constexpr int kBorderAgentServiceDummyPort = 49152;
 
 /**
  * Locators
@@ -226,7 +228,9 @@ void BorderAgent::Start(void)
     mServiceInstanceName = GetServiceInstanceNameWithExtAddr(mBaseServiceInstanceName);
     UpdateMeshCopService();
 
+#if OTBR_ENABLE_EPSKC
     otBorderAgentSetEphemeralKeyCallback(mHost.GetInstance(), BorderAgent::HandleEpskcStateChanged, this);
+#endif
 }
 
 void BorderAgent::Stop(void)
@@ -235,6 +239,7 @@ void BorderAgent::Stop(void)
     UnpublishMeshCopService();
 }
 
+#if OTBR_ENABLE_EPSKC
 void BorderAgent::HandleEpskcStateChanged(void *aContext)
 {
     BorderAgent *borderAgent = static_cast<BorderAgent *>(aContext);
@@ -295,6 +300,7 @@ void BorderAgent::UnpublishEpskcService()
                       kBorderAgentEpskcServiceType);
     });
 }
+#endif
 
 void BorderAgent::HandleMdnsState(Mdns::Publisher::State aState)
 {
diff --git a/src/border_agent/border_agent.hpp b/src/border_agent/border_agent.hpp
index 58f84a058a9..5cf42317956 100644
--- a/src/border_agent/border_agent.hpp
+++ b/src/border_agent/border_agent.hpp
@@ -151,9 +151,11 @@ class BorderAgent : private NonCopyable
     std::string GetServiceInstanceNameWithExtAddr(const std::string &aServiceInstanceName) const;
     std::string GetAlternativeServiceInstanceName() const;
 
+#if OTBR_ENABLE_EPSKC
     static void HandleEpskcStateChanged(void *aContext);
     void        PublishEpskcService(void);
     void        UnpublishEpskcService(void);
+#endif
 
     otbr::Ncp::RcpHost &mHost;
     Mdns::Publisher    &mPublisher;
diff --git a/src/ncp/ncp_spinel.cpp b/src/ncp/ncp_spinel.cpp
index 21a1952778f..685bbcd8c2c 100644
--- a/src/ncp/ncp_spinel.cpp
+++ b/src/ncp/ncp_spinel.cpp
@@ -69,9 +69,10 @@ void NcpSpinel::GetDeviceRole(GetDeviceRoleHandler aHandler)
 {
     otError      error = OT_ERROR_NONE;
     spinel_tid_t tid   = GetNextTid();
-    va_list      args;
+    va_list      args  = {};
 
     error = mSpinelDriver->SendCommand(SPINEL_CMD_PROP_VALUE_GET, SPINEL_PROP_NET_ROLE, tid, nullptr, args);
+
     if (error != OT_ERROR_NONE)
     {
         FreeTid(tid);