diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index a9cd779..fa8a998 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -465,6 +465,7 @@ static struct synth_field *parse_synth_field(int argc, const char **argv,
 	struct synth_field *field;
 	const char *prefix = NULL, *field_type = argv[0], *field_name, *array;
 	int len, ret = 0;
+	ssize_t size;
 
 	if (field_type[0] == ';')
 		field_type++;
@@ -520,11 +521,12 @@ static struct synth_field *parse_synth_field(int argc, const char **argv,
 			field->type[len - 1] = '\0';
 	}
 
-	field->size = synth_field_size(field->type);
-	if (!field->size) {
+	size = synth_field_size(field->type);
+	if (size <= 0) {
 		ret = -EINVAL;
 		goto free;
 	}
+	field->size = size;
 
 	if (synth_field_is_string(field->type))
 		field->is_string = true;