Use Ustrlen() on a uschar

diff --git a/src/src/expand.c b/src/src/expand.c
index c0edef651e8bd7c6485e16a36380f75b1c512713..88a5ee399db9c15c2a94cd95aae6f364afab3249 100644 (file)
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -5908,7 +5908,7 @@ while (*s != 0)
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_sha256(*(void **)vp->value);
-         yield = string_cat(yield, &size, &ptr, cp, (int)strlen(cp));
+         yield = string_cat(yield, &size, &ptr, cp, (int)Ustrlen(cp));
          }
        else
 #endif