diff --git a/os/access.c b/os/access.c
index 8828e0834..97246160c 100644
--- a/os/access.c
+++ b/os/access.c
@@ -1137,12 +1137,12 @@ ComputeLocalClient(ClientPtr client)
         /* Cut off any colon and whatever comes after it, see
          * https://lists.freedesktop.org/archives/xorg-devel/2015-December/048164.html
          */
-        cmd = strtok(cmd, ":");
+        char *tok = strtok(cmd, ":");
 
 #if !defined(WIN32) || defined(__CYGWIN__)
-        ret = strcmp(basename(cmd), "ssh") != 0;
+        ret = strcmp(basename(tok), "ssh") != 0;
 #else
-        ret = strcmp(cmd, "ssh") != 0;
+        ret = strcmp(tok, "ssh") != 0;
 #endif
 
         free(cmd);