wallet: remove unused code #36127

1. 
   jeanpablojp commented at 1:04 PM on August 31, 2026: contributor

   Six unused items in src/wallet, one per commit.

   DescriptorScriptPubKeyMan::AddDescriptorKey, a private wrapper that lost its caller in #28333.

   COutput::ToString, no callers. It was used by COutput::print(), which went away with the other print() methods in wallet.

   The two CHDChain keypool index members, whose last uses went away with LegacySPKM in #28710.

   WalletDatabase::m_refcount. Only BDB ever maintained it, and BDB went away in #28710.

   The warnings parameter of CreateFromDump, never written, along with the loop that printed it in wallet-tool. The push_back went away with the -format option in #31250.

   The two BDB-only members of DatabaseOptions, use_shared_memory and max_log_mb. Their last readers went away with BDB in #28710, along with the -privdb and -dblogsize options that set them.

2. wallet: remove unused DescriptorScriptPubKeyMan::AddDescriptorKey

   The private method has no callers. It opened a `WalletBatch` and
   forwarded to `AddDescriptorKeyWithDB`, which is still called from two
   other places.
   
   Its last caller, in `CWallet::AddWalletDescriptor`, was replaced in
   aa4f7823aa ("wallet: include keys when constructing DescriptorSPKM
   during import"), which builds the manager with `CreateFromMigration`
   instead of adding the key afterwards.

   a0e9aac428
3. wallet: remove unused COutput::ToString

   No callers. It was used by `COutput::print()`, which was removed in
   3802224110 ("Remove all other print() methods").

   4afc7bc40d
4. wallet: remove unused CHDChain keypool index members

   `m_next_external_index` and `m_next_internal_index` are declared and
   initialized and never read or written afterwards. Their last uses were
   removed in 83af1a3cca ("wallet: Delete LegacySPKM"). Neither appears in
   `SERIALIZE_METHODS` or in `SetNull`.

   f64b3fa70f
5. wallet: remove unused WalletDatabase::m_refcount

   The counter is never incremented. Only the BDB implementation ever
   maintained it, and that went away in 04a7a7a28c ("build, wallet, doc:
   Remove BDB"). `AddRef()` and `RemoveRef()`, which the comment above the
   member describes as maintaining it, were removed in c0f3f3264f
   ("wallet: Remove unused db functions"), leaving the member behind.

   2f6aa41d3d
6. wallet: remove unused warnings parameter from CreateFromDump

   `CreateFromDump` never writes to the vector, so the loop that prints it
   in wallet-tool cannot produce output. `tool_wallet.py` already asserts
   empty output for `createfromdump`.
   
   The only `warnings.push_back()` was removed in 7a41c939f0 ("wallet:
   Remove -format and bdb from wallet tool's createfromdump").

   bbed824a64
7. DrahtBot added the label Wallet on Aug 31, 2026
8. 
   DrahtBot commented at 1:04 PM on August 31, 2026: contributor

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   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

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   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/36127.

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   Reviews

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   Type	Reviewers
   ACK	pablomartin4btc, vicjuma
   Stale ACK	Eunovo

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9. 
   pablomartin4btc commented at 6:10 PM on August 31, 2026: member

   ACK bbed824a64f0a5335442261b3abd63db22453cd6

   Clean removal, verified every symbol's references.

   Found one more piece of unused code that would make a natural 6th commit for the PR — these 2 data members in struct DatabaseOptions:

   bool use_shared_memory = false; //!< Let other processes access the database.
   int64_t max_log_mb = 100;       //!< Max log size to allow before consolidating.
   

   Both use_shared_memory and max_log_mb were last actually consumed in 04a7a7a28c — part of the merge for PR #28710, the same PR the existing commits already cite for the m_next_* and m_refcount removals.

10. 
    vicjuma commented at 11:26 AM on September 1, 2026: contributor

    ACK bbed824a64f0a5335442261b3abd63db22453cd6

11. 
    Eunovo commented at 11:50 AM on September 1, 2026: contributor

    ACK https://github.com/bitcoin/bitcoin/pull/36127/commits/bbed824a64f0a5335442261b3abd63db22453cd6

12. wallet: remove unused DatabaseOptions members

    `use_shared_memory` and `max_log_mb` are never read or written; they
    only ever hold their initializers. Their last readers, in
    `GetBerkeleyEnv()` and the `BerkeleyDatabase` constructor, were removed
    in 04a7a7a28c ("build, wallet, doc: Remove BDB"), along with the
    `-privdb` and `-dblogsize` options that set them.
    
    Co-authored-by: pablomartin4btc <pablomartin4btc@gmail.com>

    9f0543d69a
13. 
    jeanpablojp commented at 12:51 PM on September 1, 2026: contributor

    Pushed a sixth commit taking @pablomartin4btc's suggestion, use_shared_memory and max_log_mb in DatabaseOptions. Their last readers went with BDB in #28710, same as m_refcount, along with the -privdb and -dblogsize options that set them. Credited on the commit.

14. 
    pablomartin4btc commented at 1:21 PM on September 1, 2026: member

    ACK 9f0543d69a1357371017c8289d9addc457b6f132

15. DrahtBot requested review from Eunovo on Sep 1, 2026
16. 
    vicjuma commented at 1:29 PM on September 1, 2026: contributor

    ACK 9f0543d69a1357371017c8289d9addc457b6f132

17. 
    pablomartin4btc commented at 4:06 PM on September 1, 2026: member

    reACK

    Mmm... I think the @DrahtBot hasn't properly counted @vicjuma's ACK...

    | Type | Reviewers | | ---------| ---------| | ACK | pablomartin4btc | | Concept ACK | vicjuma | | Stale ACK | Eunovo |

18. 
    maflcko commented at 5:34 PM on September 1, 2026: member

    Mmm... I think the @DrahtBot hasn't properly counted @vicjuma's ACK...

    You can find more details on code review in https://github.com/bitcoin/bitcoin/blob/master/CONTRIBUTING.md#code-review. (Without a hash, no one can know what the comment is referring to)

19. 
    vicjuma commented at 5:41 PM on September 1, 2026: contributor

    Mmm... I think the @DrahtBot hasn't properly counted @vicjuma's ACK...

    You can find more details on code

    thanks @maflcko and @pablomartin4btc

20. in src/wallet/wallettool.cpp:165 in 9f0543d69a

     161 | @@ -162,11 +162,7 @@ bool ExecuteWalletToolFunc(const ArgsManager& args, const std::string& command)
     162 |          return ret;
     163 |      } else if (command == "createfromdump") {
     164 |          bilingual_str error;
     165 | -        std::vector<bilingual_str> warnings;
     166 | -        bool ret = CreateFromDump(args, name, path, error, warnings);
     167 | -        for (const auto& warning : warnings) {
     168 | -            tfm::format(std::cout, "%s\n", warning.original);
     169 | -        }
     170 | +        bool ret = CreateFromDump(args, name, path, error);
    

    ---

    ---

    

    fanquake commented at 1:08 PM on September 7, 2026:

    Looks like the last use of warnings in CreateFromDrump was removed in 7a41c939f05f2208c33e8f09eecbbfd579fb4023.

21. fanquake merged this on Sep 7, 2026
22. fanquake closed this on Sep 7, 2026

    ---

23. jeanpablojp deleted the branch on Sep 8, 2026

Review Requested
Eunovo