(MULTIBYTE_BYTES_WIDTH): Check validity of a multibyte character.

1 files changed, 9 insertions, 5 deletions

diff --git a/src/indent.c b/src/indent.c
index 9ac2dd7315f..9528894baf2 100644
--- a/src/indent.c
+++ b/src/indent.c
@@ -308,13 +308,17 @@ skip_invisible (pos, next_boundary_p, to, window)
         bytes = BYTES_BY_CHAR_HEAD (c);                                 \
         if (bytes >= 2 && bytes <= pend - p)                            \
           {                                                             \
-            int ch;                                                     \
+            int ch = STRING_CHAR (p, bytes);                            \
                                                                         \
-            if (dp && (ch = STRING_CHAR (p, bytes),                     \
-                       VECTORP (DISP_CHAR_VECTOR (dp, ch))))            \
-              width = XVECTOR (DISP_CHAR_VECTOR (dp, ch))->size;        \
+            if (CHAR_VALID_P (ch, 0))                                   \
+              {                                                         \
+                if (dp && VECTORP (DISP_CHAR_VECTOR (dp, ch)))          \
+                  width = XVECTOR (DISP_CHAR_VECTOR (dp, ch))->size;    \
+                else                                                    \
+                  width = WIDTH_BY_CHAR_HEAD (c);                       \
+              }                                                         \
             else                                                        \
-              width = WIDTH_BY_CHAR_HEAD (c);                           \
+              width = bytes * 4;                                        \
             if (width > 1)                                              \
               wide_column = width;                                      \
           }                                                             \