53796: fix local reference chains and detect self-reference across local scopes

Author: paltherr

ChangeLog

@@ -11,6 +11,9 @@
 	omit base level for up-scope references; do not follow reference
 	chains when computing base level of new references
 
+	* Philippe: 53796: Src/params.c, Test/K01nameref.ztst: fix local
+	reference chains and detect self-reference across local scopes
+
 2025-10-24  Oliver Kiddle  <[email protected]>
 
 	* 54002: Src/parse.c: silence compiler warning for static function

Src/params.c

@@ -6412,8 +6412,6 @@ setscope(Param pm)
 	stop.name = pm->node.nam;
 	stop.value.scalar = NULL;
 	stop.flags = PM_NAMEREF;
-	if (locallevel && !(pm->node.flags & PM_UPPER))
-	    stop.flags |= PM_LOCAL;
 	dont_queue_signals();	/* Prevent unkillable loops */
 	basepm = (Param)resolve_nameref(pm, &stop);
 	restore_queue_signals(q);

Test/K01nameref.ztst

@@ -1179,6 +1179,16 @@ F:previously this could create an infinite recursion and crash
 >typeset PS1=zz
 *?*
 
+ typeset -n ref1
+ typeset -n ref2=ref1
+ () {
+   typeset -n ref3=ref2
+   typeset ref2=foo
+   ref1=ref3
+ }
+1:self reference chain including a hidden reference
+?(anon):3: ref3: invalid self reference
+
  zmodload -u zsh/random
  echo z=${(M)${(f)${ zmodload -ap}}:#*SRANDOM*}
  typeset -n ref=SRANDOM