merge revision(s) 9726736006b3f74635fd8af05814fe0908e2cf84: [Backport #19327]

	Set STR_SHARED_ROOT flag on root of string

	---
	 string.c | 1 +
	 1 file changed, 1 insertion(+)

1 files changed, 1 insertions, 0 deletions

diff --git a/string.c b/string.c
index cae87907c3..6773ed2d86 100644
--- a/string.c
+++ b/string.c
@@ -1787,6 +1787,7 @@ str_duplicate_setup(VALUE klass, VALUE str, VALUE dup)
         else {
             RSTRING(dup)->as.heap.len = RSTRING_LEN(str);
             RSTRING(dup)->as.heap.ptr = RSTRING_PTR(str);
+            FL_SET(root, STR_SHARED_ROOT);
             RB_OBJ_WRITE(dup, &RSTRING(dup)->as.heap.aux.shared, root);
             flags |= RSTRING_NOEMBED | STR_SHARED;
         }