diff --git a/channels/urbdrc/common/msusb.c b/channels/urbdrc/common/msusb.c
index 73bde87dd..98d219276 100644
--- a/channels/urbdrc/common/msusb.c
+++ b/channels/urbdrc/common/msusb.c
@@ -103,7 +103,7 @@ out_error:
 	return NULL;
 }
 
-static MSUSB_INTERFACE_DESCRIPTOR* msusb_msinterface_new()
+static MSUSB_INTERFACE_DESCRIPTOR* msusb_msinterface_new(void)
 {
 	return (MSUSB_INTERFACE_DESCRIPTOR*)calloc(1, sizeof(MSUSB_INTERFACE_DESCRIPTOR));
 }
diff --git a/libfreerdp/codec/nsc_encode.c b/libfreerdp/codec/nsc_encode.c
index 3a1422a9b..44798da1d 100644
--- a/libfreerdp/codec/nsc_encode.c
+++ b/libfreerdp/codec/nsc_encode.c
@@ -140,8 +140,8 @@ static BOOL nsc_encode_argb_to_aycocg(NSC_CONTEXT* context, const BYTE* data, UI
 		coplane = context->priv->PlaneBuffers[1] + y * rw;
 		cgplane = context->priv->PlaneBuffers[2] + y * rw;
 		aplane = context->priv->PlaneBuffers[3] + y * context->width;
-		src_32 = (UINT32*)src;
-		src_16 = (UINT16*)src;
+		src_32 = (const UINT32*)src;
+		src_16 = (const UINT16*)src;
 
 		for (x = 0; x < context->width; x++)
 		{
diff --git a/libfreerdp/codec/rfx_encode.c b/libfreerdp/codec/rfx_encode.c
index ec75d4729..1bfaf3164 100644
--- a/libfreerdp/codec/rfx_encode.c
+++ b/libfreerdp/codec/rfx_encode.c
@@ -57,8 +57,8 @@ static void rfx_encode_format_rgb(const BYTE* rgb_data, int width, int height, i
 	for (y = 0; y < height; y++)
 	{
 		src = rgb_data + y * rowstride;
-		src_32 = (UINT32*)src;
-		src_16 = (UINT16*)src;
+		src_32 = (const UINT32*)src;
+		src_16 = (const UINT16*)src;
 
 		switch (pixel_format)
 		{
diff --git a/libfreerdp/core/childsession.c b/libfreerdp/core/childsession.c
index 082306566..649c5f305 100644
--- a/libfreerdp/core/childsession.c
+++ b/libfreerdp/core/childsession.c
@@ -137,13 +137,13 @@ static long transport_bio_named_ctrl(BIO* bio, int cmd, long arg1, void* arg2)
 			int timeout = (int)arg1;
 			return 1;
 		}
-		break;
+
 		case BIO_C_WAIT_WRITE:
 		{
 			int timeout = (int)arg1;
 			return 1;
 		}
-		break;
+
 		default:
 			break;
 	}
@@ -224,7 +224,7 @@ static int transport_bio_named_free(BIO* bio)
 	return 1;
 }
 
-BIO_METHOD* BIO_s_namedpipe(void)
+static BIO_METHOD* BIO_s_namedpipe(void)
 {
 	static BIO_METHOD* bio_methods = NULL;
 
@@ -246,7 +246,7 @@ BIO_METHOD* BIO_s_namedpipe(void)
 }
 
 typedef NTSTATUS (*WinStationCreateChildSessionTransportFn)(WCHAR* path, DWORD len);
-BOOL createChildSessionTransport(HANDLE* pFile)
+static BOOL createChildSessionTransport(HANDLE* pFile)
 {
 	WINPR_ASSERT(pFile);
 
diff --git a/libfreerdp/core/gateway/arm.c b/libfreerdp/core/gateway/arm.c
index d522812db..f6c55fd03 100644
--- a/libfreerdp/core/gateway/arm.c
+++ b/libfreerdp/core/gateway/arm.c
@@ -451,8 +451,8 @@ static BOOL arm_stringEncodeW(const BYTE* pin, size_t cbIn, BYTE** ppOut, size_t
 	return TRUE;
 }
 
-BOOL arm_encodeRedirectPasswd(rdpSettings* settings, const rdpCertificate* cert,
-                              WINPR_CIPHER_CTX* cipher)
+static BOOL arm_encodeRedirectPasswd(rdpSettings* settings, const rdpCertificate* cert,
+                                     WINPR_CIPHER_CTX* cipher)
 {
 	BOOL ret = FALSE;
 	BYTE* output = NULL;
diff --git a/winpr/libwinpr/utils/wlog/Layout.c b/winpr/libwinpr/utils/wlog/Layout.c
index ae48b418c..b9872bf4d 100644
--- a/winpr/libwinpr/utils/wlog/Layout.c
+++ b/winpr/libwinpr/utils/wlog/Layout.c
@@ -70,7 +70,7 @@ struct format_option_recurse
 /**
  * Log Layout
  */
-
+WINPR_ATTR_FORMAT_ARG(3, 0)
 static void WLog_PrintMessagePrefixVA(wLog* log, wLogMessage* message, const char* format,
                                       va_list args)
 {
@@ -78,6 +78,7 @@ static void WLog_PrintMessagePrefixVA(wLog* log, wLogMessage* message, const cha
 	vsnprintf(message->PrefixString, WLOG_MAX_PREFIX_SIZE - 1, format, args);
 }
 
+WINPR_ATTR_FORMAT_ARG(3, 4)
 static void WLog_PrintMessagePrefix(wLog* log, wLogMessage* message, const char* format, ...)
 {
 	va_list args;