1 files changed, 1 insertions, 1 deletions
diff --git a/src/utf8.h b/src/utf8.h
index 901b1af..59a959e 100644
--- a/src/utf8.h
+++ b/src/utf8.h
@@ -8,7 +8,7 @@
 uint32_t utf8_nchars(uint8_t *bytes, uint32_t nbytes);
 
 /* Return the number of bytes used to make up the next `nchars` characters */
-uint32_t utf8_nbytes(uint8_t *bytes, uint32_t nchars);
+uint32_t utf8_nbytes(uint8_t *bytes, uint32_t nbytes, uint32_t nchars);
 
 /* true if `byte` is a unicode byte sequence start byte */
 bool utf8_byte_is_unicode_start(uint8_t byte);