diff --git a/qemu/qapi/string-input-visitor.c b/qemu/qapi/string-input-visitor.c
index 8180be3f..9661f91f 100644
--- a/qemu/qapi/string-input-visitor.c
+++ b/qemu/qapi/string-input-visitor.c
@@ -54,6 +54,10 @@ static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
         return 0;
     }
 
+    if (!*str) {
+        return 0;
+    }
+
     do {
         errno = 0;
         start = strtoll(str, &endptr, 0);