1 files changed, 1 insertions, 0 deletions
diff --git a/string.c b/string.c
index 68fcfc2852..f770118660 100644
--- a/string.c
+++ b/string.c
@@ -60,6 +60,7 @@ VALUE rb_cSymbol;
  * 7:     STR_TMPLOCK
  * 8-9:   ENC_CODERANGE (2 bits)
  * 10-16: ENCODING (7 bits == 128)
+ * 17:    RSTRING_FSTR
  * 18:    STR_NOFREE
  * 19:    STR_FAKESTR
  */