X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/7da629c2abc50b798dbb25c2badd0e98ee702f79..d403792172617a7b719e2bb4600ad312011dd787:/cmdgen.c

diff --git a/cmdgen.c b/cmdgen.c
index 9aa585f3..ae405208 100644
--- a/cmdgen.c
+++ b/cmdgen.c
@@ -119,7 +119,7 @@ void sk_cleanup(void)
 void showversion(void)
 {
     char *verstr = dupstr(ver);
-    verstr[0] = tolower(verstr[0]);
+    verstr[0] = tolower((unsigned char)verstr[0]);
     printf("PuTTYgen %s\n", verstr);
     sfree(verstr);
 }