1 files changed, 6 insertions, 1 deletions
diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index 7426f788374..d8c038ccf6c 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -11793,7 +11793,12 @@ set_underlying_type (tree x)
       tt = build_variant_type_copy (tt);
       TYPE_STUB_DECL (tt) = TYPE_STUB_DECL (DECL_ORIGINAL_TYPE (x));
       TYPE_NAME (tt) = x;
-      TREE_USED (tt) = TREE_USED (x);
+
+      /* Mark the type as used only when its type decl is decorated
+	 with attribute unused.  */
+      if (lookup_attribute ("unused", DECL_ATTRIBUTES (x)))
+	TREE_USED (tt) = 1;
+
       TREE_TYPE (x) = tt;
     }
 }