Check by eassert that a bytepos argument isn't in the middle of a character

* src/marker.c (buf_bytepos_to_charpos): Add an eassert to check that the
parameter bytepos is at the beginning of a character or EOB.

diff --git a/src/marker.c b/src/marker.c
index b58051a8c2b9dc2739f804b8e9034d441345d013..0b2e1bf5c6b8f78b5db09e84d7e0420f5d374067 100644 (file)
--- a/src/marker.c
+++ b/src/marker.c
@@ -332,6 +332,10 @@ buf_bytepos_to_charpos (struct buffer *b, ptrdiff_t bytepos)
   if (best_above == best_above_byte)
     return bytepos;
 
+  /* Check bytepos is not in the middle of a character. */
+  eassert (bytepos >= BUF_Z_BYTE (b)
+           || CHAR_HEAD_P (BUF_FETCH_BYTE (b, bytepos)));
+
   best_below = BEG;
   best_below_byte = BEG_BYTE;