blockchain: fix setting non trovial alternate chain as invalid

The wrong iterator was being used.
Also preincrement iterators to avoid possibly invalidating them,
I'm not sure this is necessary, but let's be safe.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index df9c0f3f3..df24204f8 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -832,12 +832,12 @@ bool Blockchain::switch_to_alternative_blockchain(std::list<blocks_ext_by_hash::
       // looking into.
       add_block_as_invalid(ch_ent->second, get_block_hash(ch_ent->second.bl));
       LOG_PRINT_L1("The block was inserted as invalid while connecting new alternative chain, block_id: " << get_block_hash(ch_ent->second.bl));
-      m_alternative_chains.erase(ch_ent);
+      m_alternative_chains.erase(*alt_ch_iter++);
 
-      for(auto alt_ch_to_orph_iter = ++alt_ch_iter; alt_ch_to_orph_iter != alt_chain.end(); alt_ch_to_orph_iter++)
+      for(auto alt_ch_to_orph_iter = alt_ch_iter; alt_ch_to_orph_iter != alt_chain.end(); )
       {
-        add_block_as_invalid((*alt_ch_iter)->second, (*alt_ch_iter)->first);
-        m_alternative_chains.erase(*alt_ch_to_orph_iter);
+        add_block_as_invalid((*alt_ch_to_orph_iter)->second, (*alt_ch_to_orph_iter)->first);
+        m_alternative_chains.erase(*alt_ch_to_orph_iter++);
       }
       return false;
     }