diff --git a/src/message.c b/src/message.c
index 41dfffb..bf340d0 100644
--- a/src/message.c
+++ b/src/message.c
@@ -1390,7 +1390,7 @@
 									attr);
 		plain_start = str + 1;
 		msg_puts_attr(s, attr == 0 ? hl_attr(HLF_8) : attr);
-		retval += STRLEN(s);
+		retval += (int)STRLEN(s);
 	    }
 	    else
 		++retval;