Stop using deprecated std::iterator

As reported in #4615 and others, GCC 12.1 emits deprecation warnings
because we use std::iterator. Replace it with the modern equivalent.

Closes #4615

1 files changed, 7 insertions, 1 deletions

diff --git a/src/parameters_parser.hh b/src/parameters_parser.hh
index afc2c7dc..69fa88eb 100644
--- a/src/parameters_parser.hh
+++ b/src/parameters_parser.hh
@@ -80,8 +80,14 @@ struct ParametersParser
     // a non empty StringView value if the switch took an argument.
     Optional<StringView> get_switch(StringView name) const;
 
-    struct iterator : std::iterator<std::forward_iterator_tag, String>
+    struct iterator
     {
+        using difference_type = ptrdiff_t;
+        using value_type = String;
+        using pointer = String*;
+        using reference = String&;
+        using iterator_category = std::forward_iterator_tag;
+
         iterator(const ParametersParser& parser, size_t index)
             : m_parser(parser), m_index(index) {}