diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index a564577..4d9e98f 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -86,6 +86,10 @@ add_library(chiaki-lib ${HEADER_FILES} ${SOURCE_FILES} ${CHIAKI_LIB_PROTO_SOURCE
 configure_file(config.h.in include/chiaki/config.h)
 target_include_directories(chiaki-lib PUBLIC "${CMAKE_CURRENT_BINARY_DIR}/include")
 
+if(CMAKE_C_COMPILER_ID STREQUAL GNU OR CMAKE_C_COMPILER_ID STREQUAL Clang)
+	target_compile_options(chiaki-lib PRIVATE -Wall)
+endif()
+
 add_dependencies(chiaki-lib chiaki-pb)
 set_target_properties(chiaki-lib PROPERTIES OUTPUT_NAME chiaki)
 
diff --git a/lib/src/base64.c b/lib/src/base64.c
index 297eb3e..5882ff8 100644
--- a/lib/src/base64.c
+++ b/lib/src/base64.c
@@ -110,7 +110,7 @@ CHIAKI_EXPORT ChiakiErrorCode chiaki_base64_decode(const char *in, size_t in_siz
 
 	while (in < end)
 	{
-		unsigned char c = d[*in++];
+		unsigned char c = d[(size_t)(*in++)];
 
 		switch(c)
 		{
@@ -153,4 +153,4 @@ CHIAKI_EXPORT ChiakiErrorCode chiaki_base64_decode(const char *in, size_t in_siz
 
 	*out_size = len;
 	return CHIAKI_ERR_SUCCESS;
-}
\ No newline at end of file
+}
diff --git a/lib/src/ctrl.c b/lib/src/ctrl.c
index 4fc768c..b410741 100644
--- a/lib/src/ctrl.c
+++ b/lib/src/ctrl.c
@@ -157,6 +157,7 @@ CHIAKI_EXPORT ChiakiErrorCode chiaki_ctrl_send_message(ChiakiCtrl *ctrl, uint16_
 	}
 	chiaki_mutex_unlock(&ctrl->notif_mutex);
 	chiaki_stop_pipe_stop(&ctrl->notif_pipe);
+	return CHIAKI_ERR_SUCCESS;
 }
 
 CHIAKI_EXPORT void chiaki_ctrl_set_login_pin(ChiakiCtrl *ctrl, const uint8_t *pin, size_t pin_size)
diff --git a/lib/src/pb_utils.h b/lib/src/pb_utils.h
index d01b204..70ecd5a 100644
--- a/lib/src/pb_utils.h
+++ b/lib/src/pb_utils.h
@@ -6,7 +6,7 @@
 #include <pb_encode.h>
 #include <pb_decode.h>
 
-static bool chiaki_pb_encode_string(pb_ostream_t *stream, const pb_field_t *field, void *const *arg)
+static inline bool chiaki_pb_encode_string(pb_ostream_t *stream, const pb_field_t *field, void *const *arg)
 {
 	char *str = *arg;
 
@@ -22,7 +22,7 @@ typedef struct chiaki_pb_buf_t
 	uint8_t *buf;
 } ChiakiPBBuf;
 
-static bool chiaki_pb_encode_buf(pb_ostream_t *stream, const pb_field_t *field, void *const *arg)
+static inline bool chiaki_pb_encode_buf(pb_ostream_t *stream, const pb_field_t *field, void *const *arg)
 {
 	ChiakiPBBuf *buf = *arg;
 
@@ -40,7 +40,7 @@ typedef struct chiaki_pb_decode_buf_t
 	uint8_t *buf;
 } ChiakiPBDecodeBuf;
 
-static bool chiaki_pb_decode_buf(pb_istream_t *stream, const pb_field_t *field, void **arg)
+static inline bool chiaki_pb_decode_buf(pb_istream_t *stream, const pb_field_t *field, void **arg)
 {
 	ChiakiPBDecodeBuf *buf = *arg;
 	if(stream->bytes_left > buf->max_size)
@@ -63,7 +63,7 @@ typedef struct chiaki_pb_decode_buf_alloc_t
 	uint8_t *buf;
 } ChiakiPBDecodeBufAlloc;
 
-static bool chiaki_pb_decode_buf_alloc(pb_istream_t *stream, const pb_field_t *field, void **arg)
+static inline bool chiaki_pb_decode_buf_alloc(pb_istream_t *stream, const pb_field_t *field, void **arg)
 {
 	ChiakiPBDecodeBufAlloc *buf = *arg;
 	buf->size = stream->bytes_left;
diff --git a/lib/src/session.c b/lib/src/session.c
index c0850d8..fd1411d 100644
--- a/lib/src/session.c
+++ b/lib/src/session.c
@@ -334,14 +334,6 @@ static bool session_check_state_pred_pin(void *user)
 		   || session->login_pin_entered;
 }
 
-static bool session_check_state_pred_session_id(void *user)
-{
-	ChiakiSession *session = user;
-	return session->should_stop
-		   || session->ctrl_failed
-		   || session->ctrl_session_id_received;
-}
-
 #define ENABLE_SENKUSHA
 
 static void *session_thread_func(void *arg)
diff --git a/lib/src/takion.c b/lib/src/takion.c
index 36374f8..dcb26f2 100644
--- a/lib/src/takion.c
+++ b/lib/src/takion.c
@@ -1273,7 +1273,7 @@ CHIAKI_EXPORT ChiakiErrorCode chiaki_takion_v9_av_packet_parse(ChiakiTakionAVPac
 	uint32_t key_pos_low = ntohl(*((chiaki_unaligned_uint32_t *)(av + 0xd)));
 	packet->key_pos = chiaki_key_state_request_pos(key_state, key_pos_low, true);
 
-	uint8_t unknown_1 = av[0x11];
+	uint8_t unknown_1 = av[0x11]; (void)unknown_1;
 
 	av += 0x11;
 	av_size -= 0x11;