1 files changed, 2 insertions, 0 deletions

diff --git a/src/buffer.c b/src/buffer.c
index 6e3412c3d05..c6f9eb28e25 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -5620,6 +5620,8 @@ file I/O and the behavior of various editing commands.
 
 This variable is buffer-local but you cannot set it directly;
 use the function `set-buffer-multibyte' to change a buffer's representation.
+To prevent any attempts to set it or make it buffer-local, Emacs will
+signal an error in those cases.
 See also Info node `(elisp)Text Representations'.  */);
   make_symbol_constant (intern_c_string ("enable-multibyte-characters"));