Remove fixed locals for iterators

Also fixes a bug in JIT affecting caseful matching of backreferences.

Author: zherczeg

ChangeLog

@@ -107,6 +107,10 @@ well as interpreting \b and \v as characters.
 24. Fixed a bug in JIT affecting greedy bounded repeats. The upper limit of
 repeats inside a repeated bracket might be incorrectly checked.
 
+25. Fixed a bug in JIT affecting caseful matching of backreferences. When
+utf is disabled, and dupnames is enabled, casesless matching is used instead
+of caseful matching.
+
 
 Version 10.44 07-June-2024
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