diff --git a/packaging/tags.py b/packaging/tags.py
index 20512aaf9..1c1430a4d 100644
--- a/packaging/tags.py
+++ b/packaging/tags.py
@@ -328,8 +328,7 @@ def compatible_tags(
     """
     if not python_version:
         python_version = sys.version_info[:2]
-    if not platforms:
-        platforms = _platform_tags()
+    platforms = list(platforms or _platform_tags())
     for version in _py_interpreter_range(python_version):
         for platform_ in platforms:
             yield Tag(version, "none", platform_)