[gcc r12-448] libstdc++: Fix null dereference in pb_ds containers

[Jonathan Wakely]

https://gcc.gnu.org/g:ca871701c2822c3c4537745d4aa44a7b8f408337

commit r12-448-gca871701c2822c3c4537745d4aa44a7b8f408337
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue May 4 15:46:28 2021 +0100

    libstdc++: Fix null dereference in pb_ds containers
    
    This fixes ubsan errors:
    
    ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp:533:15: runtime error: member access within null pointer of type 'struct entry'
    
    libstdc++-v3/ChangeLog:
    
            * include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp
            (find_key_pointer(key_const_reference, false_type))
            (find_key_pointer(key_const_reference, true_type)): Do not
            dereference null pointer.

Diff:
---
 .../pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp | 26 +++++++++++++---------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/libstdc++-v3/include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp b/libstdc++-v3/include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp
index aa5c94b9aed..c81bf3abfef 100644
--- a/libstdc++-v3/include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp
+++ b/libstdc++-v3/include/ext/pb_ds/detail/cc_hash_table_map_/cc_ht_map_.hpp
@@ -524,13 +524,16 @@ namespace __gnu_pbds
 
 	resize_base::notify_find_search_end();
 
-#ifdef _GLIBCXX_DEBUG
 	if (p_e == 0)
-	  PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
+	  {
+	    PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
+	    return 0;
+	  }
 	else
-	  PB_DS_CHECK_KEY_EXISTS(r_key)
-#endif
-	return &p_e->m_value;
+	  {
+	    PB_DS_CHECK_KEY_EXISTS(r_key)
+	    return &p_e->m_value;
+	  }
       }
 
       inline pointer
@@ -550,13 +553,16 @@ namespace __gnu_pbds
 
 	resize_base::notify_find_search_end();
 
-#ifdef _GLIBCXX_DEBUG
 	if (p_e == 0)
-	  PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
+	  {
+	    PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
+	    return 0;
+	  }
 	else
-	  PB_DS_CHECK_KEY_EXISTS(r_key)
-#endif
-	return &p_e->m_value;
+	  {
+	    PB_DS_CHECK_KEY_EXISTS(r_key)
+	    return &p_e->m_value;
+	  }
       }
 
       inline bool