Fix -Wmismatched-tags warnings #21051

1. 
   hebasto commented at 12:38 pm on February 1, 2021: member

   Warnings were introduced in #20749:

    0./validation.h:43:1: warning: class 'CCheckpointData' was previously declared as a struct; this is valid, but may result in linker errors under the Microsoft C++ ABI [-Wmismatched-tags]
    1class CCheckpointData;
    2^
    3./chainparams.h:24:8: note: previous use is here
    4struct CCheckpointData {
    5       ^
    6./validation.h:43:1: note: did you mean struct here?
    7class CCheckpointData;
    8^~~~~
    9struct
   101 warning generated.
   

   This change fixes AppVeyor build: https://ci.appveyor.com/project/DrahtBot/bitcoin/builds/37547435

2. Fix -Wmismatched-tags warnings 1485124291
3. fanquake added the label Validation on Feb 1, 2021
4. 
   jnewbery commented at 1:28 pm on February 1, 2021: member

   Code review ACK 1485124291368c4a2ca8ea09c18e813f1dbabf5c

   Thanks @hebasto!

5. 
   practicalswift commented at 3:47 pm on February 1, 2021: contributor

   cr ACK 1485124291368c4a2ca8ea09c18e813f1dbabf5c: patch looks correct

   Thanks for fixing warnings!

6. 
   hebasto commented at 4:27 pm on February 1, 2021: member

   Thanks for fixing warnings!

   Not warnings only, but MSVC builds are fixed as well :)

7. 
   dongcarl commented at 5:41 pm on February 1, 2021: member

   Code Review ACK 1485124291368c4a2ca8ea09c18e813f1dbabf5c 🤦 @dongcarl
8. ryanofsky approved
9. 
   ryanofsky commented at 8:02 pm on February 1, 2021: member

   Code review ACK. But I unclear on how appveyor failed to catch this before merging. Or maybe changes were merged despite appveyor failing? I do see appveyor errors one of my recent pushes: https://ci.appveyor.com/project/DrahtBot/bitcoin/builds/37552923

   Would be nice to know what’s going on with appveyor. Also ideally we would make either make this an error on linux, or make this not an error on windows to be consistent across platforms.

10. 
    ajtowns commented at 8:59 pm on February 1, 2021: member

    ACK 1485124291368c4a2ca8ea09c18e813f1dbabf5c

    I think adding:

    0AX_CHECK_COMPILE_FLAG([-Werror=mismatched-tags],[ERROR_CXXFLAGS="$ERROR_CXXFLAGS -Werror=mismatched-tags"],,[[$CXXFLAG_WERROR]])
    

    after the -Werror=unreachable-code-loop-increment line is all you need to make this an error for clang on linux when configuring with enable-werror.

11. build: Add -Werror=mismatched-tags b6aadcd5b4
12. 
    hebasto commented at 9:04 pm on February 1, 2021: member

    Updated.
13. 
    glozow commented at 10:39 pm on February 1, 2021: member

    utACK https://github.com/bitcoin/bitcoin/pull/21051/commits/b6aadcd5b4350a6ebcd57e88e7a0853cedf7c2fb 🚗

    Thanks @hebasto, u so fast ⚡

14. 
    practicalswift commented at 10:41 pm on February 1, 2021: contributor

    cr ACK b6aadcd5b4350a6ebcd57e88e7a0853cedf7c2fb: patch looks correct
15. 
    DrahtBot commented at 11:48 pm on February 1, 2021: member

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

    Conflicts

    Reviewers, this pull request conflicts with the following ones:

    • #20544 (build: Do not repeat warning names in -Werror=… options by hebasto)

    If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

16. fanquake merged this on Feb 2, 2021
17. fanquake closed this on Feb 2, 2021

    ---

18. 
    jnewbery commented at 8:19 am on February 2, 2021: member

    But I unclear on how appveyor failed to catch this before merging. Or maybe changes were merged despite appveyor failing?

    This is at least partially my fault. I encouraged @laanwj to merge #20749. I’d seen a “QT download hash mismatch” error in appveyor and assumed it was spurious.

19. hebasto deleted the branch on Feb 2, 2021
20. 
    laanwj commented at 6:05 pm on February 2, 2021: member

    Appveyor is flaky enough, and has been flaky enough historically (with really strange issues like sudden compiler upgrades breaking compatibility) that I must admit to sometimes ignore it. Sorry for that in this case.
21. sidhujag referenced this in commit 3a79b1874b on Feb 3, 2021
22. DrahtBot locked this on Aug 16, 2022

Contributors
hebasto jnewbery practicalswift dongcarl ryanofsky ajtowns glozow DrahtBot laanwj

Labels
Validation