This is a bit more complete. It removes the possibility of rflag being equal to 3, the behavior of which, AFAICT, isn't defind.

Any -R overrides any -r.

Multiple/extra instances of -r are ignored (-rr is the same as -r).

There is still an implicit -r with -x.

--- a/src/screen.c
+++ b/src/screen.c
@@ -678,24 +692,24 @@ char **av;
                 case 'q':
                   quietflag = 1;
                   break;
-                case 'r':
                 case 'R':
+                  rflag = (rflag/2) ? 4 : 2;
+                  /* FALLTHROUGH */
 #ifdef MULTI
                 case 'x':
+                  if (*ap == 'x')
+                      xflag = 1;
+                  /* FALLTHROUGH */
 #endif
+                case 'r':
+                  if (!rflag)
+                    rflag = 1;
                   if (ac > 1 && *av[1] != '-' && !SockMatch)
                     {
                       SockMatch = *++av;
                       ac--;
-                      debug2("rflag=%d, SockMatch=%s\n", dflag, SockMatch);
+                      debug2("rflag=%d, SockMatch=%s\n", rflag, SockMatch);
                     }
-#ifdef MULTI
-                  if (*ap == 'x')
-                    xflag = 1;
-#endif
-                  if (rflag)
-                    rflag = 2;
-                  rflag += (*ap == 'R') ? 2 : 1;
                   break;
 #ifdef REMOTE_DETACH
                 case 'd':

In screen.c:

                  rflag += (*ap == 'R') ? 2 : 1;

This appears to add to rflag, which might not already be initialized, accounting for inconsistency.

Patch attached.


(file #18656)