1 files changed, 1 insertions, 1 deletions

diff --git a/ssh.c b/ssh.c
index 2681ccb6b..0c950745b 100644
--- a/ssh.c
+++ b/ssh.c
@@ -629,7 +629,7 @@ main(int ac, char **av)
         if (options.host_key_alias != NULL) {
                 for (p = options.host_key_alias; *p; p++)
                         if (isupper(*p))
-                                *p = tolower(*p);
+                                *p = (char)tolower(*p);
         }
 
         /* Get default port if port has not been set. */