From: Jonathan Wakely <jwakely@redhat.com>
Date: Thu, 12 Dec 2024 20:42:19 +0000 (+0000)
Subject: libstdc++: Initialize all members of hashtable local iterators
X-Git-Tag: basepoints/gcc-16~3277
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f1309dbc7c281dc9fd70db8ec6e8cb804b2089fc;p=thirdparty%2Fgcc.git

libstdc++: Initialize all members of hashtable local iterators

Currently the _M_bucket members are left uninitialized for
default-initialized local iterators, and then copy construction copies
indeterminate values. We should just ensure they're initialized on
construction.

Setting them to zero makes default-initialization consistent with
value-initialization and avoids indeterminate values.

For the _Local_iterator_base<..., false> specialization we preserve the
existing behaviour of setting _M_bucket_count to -1 in the default
constructor, as a sentinel value to indicate there's no hash object
present.

libstdc++-v3/ChangeLog:

	* include/bits/hashtable_policy.h (_Local_iterator_base): Use
	default member-initializers.
---

diff --git a/libstdc++-v3/include/bits/hashtable_policy.h b/libstdc++-v3/include/bits/hashtable_policy.h
index b7788eb5bd78..6f46a5796ba3 100644
--- a/libstdc++-v3/include/bits/hashtable_policy.h
+++ b/libstdc++-v3/include/bits/hashtable_policy.h
@@ -1156,8 +1156,8 @@ namespace __detail
 	  }
       }
 
-      size_t _M_bucket;
-      size_t _M_bucket_count;
+      size_t _M_bucket = 0;
+      size_t _M_bucket_count = 0;
 
     public:
       size_t
@@ -1194,7 +1194,7 @@ namespace __detail
       using __hash_obj_storage = _Hash_obj_storage<_Hash>;
       using __node_iter_base = _Node_iterator_base<_Value, false>;
 
-      _Local_iterator_base() : _M_bucket_count(-1) { }
+      _Local_iterator_base() = default;
 
       _Local_iterator_base(const __hash_code_base& __base,
 			   _Hash_node<_Value, false>* __p,
@@ -1242,8 +1242,8 @@ namespace __detail
 	  }
       }
 
-      size_t _M_bucket;
-      size_t _M_bucket_count;
+      size_t _M_bucket = 0;
+      size_t _M_bucket_count = -1;
 
       void
       _M_init(const _Hash& __h)