1 files changed, 2 insertions, 0 deletions

diff --git a/src/coding.c b/src/coding.c
index 81e8e4e10bc..4e8063543fe 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -2695,6 +2695,8 @@ detect_coding_iso_2022 (coding, detect_info)
       struct coding_system *this = &(coding_categories[i]);
       Lisp_Object attrs, val;
 
+      if (this->id < 0)
+        continue;
       attrs = CODING_ID_ATTRS (this->id);
       if (CODING_ISO_FLAGS (this) & CODING_ISO_FLAG_FULL_SUPPORT
           && ! EQ (CODING_ATTR_SAFE_CHARSETS (attrs), Viso_2022_charset_list))