Bitcoin-Qt suddenly stopped with "assertion failed"

[cpunks]

Bitcoin version 0.8.1-beta
Qt version 4.8.3

Screenshot:

http://www.freeimagehosting.nl/pics/44408cb76129be8e0813ed1286be3f86.png

Background:

I have used this Bitcoin client for a while. The configuration was initialized under Windows XP, and later on transferred to a Windows 7 machine. It has worked for several months swithout any notable problems -- with the only exception of it sometimes not including a "mined" transaction into my free balance immediately as it matures (instead it needs to be restarted).

Today, about 4 hours after receiving a "mined" transaction, it then crashed telling:

Assertion failed!
File: src/main.cpp
Line: 1127
Expression: pindexFirst

After restarting, it appears to have recovered fully.

[sipa]

Are you mining?

EDIT: I mean solo-mining (or p2pool), against Bitcoin-qt?

[cpunks]

Nope, not against my local bitcoin-qt -- a different machine is mining against a pool, local client just receives the resulting bitcoins (they appear as "mined" transactions since Eligius does it that way).

[sipa]

For the record: @gmaxwell noticed yesterday that this can only be cause by the retargetting code. That should narrow down the problem a lot.

[cpunks]

Would retargeting code only run on an instance of Bitcoin intended for mining?

In that case, I have to clarify: I have in the past, used this Bitcoin instance for mining too, and now that I checked, as a historic leftover, "rpcuser" and "rpcpassword" are still set in "bitcoin.conf".

[sipa]

Sorry for the confusion. It is unrelated to mining - I asked that question before it was discovered that this assertion failure is caused by the retargetting code. I just added it here so we don't forget.

[cpunks]

However, to further clarify, I am not starting it with a "-server" command line option, so anything that results from that code path, should be excluded.

[cpunks]

Aha, thanks. If you have any additional questions, just ask. I'll check back about once a day, even if the problem is not disturbing my activities in any manner.

[bitcoinstarter]

@sipa any workaround/fix regarding this problem? I too have this issue for more than 2 weeks now.

[Diapolo]

The part of the code which triggers your problem is (in GetNextWorkRequired()):

    // Go back by what we want to be 14 days worth of blocks
    const CBlockIndex* pindexFirst = pindexLast;
    for (int i = 0; pindexFirst && i < nInterval-1; i++)
        pindexFirst = pindexFirst->pprev;
    assert(pindexFirst);

But this needs to be looked at by a core dev...

[bitcoinstarter]

@gavinandresen

Can you please take a look the problem stated by @Diapolo above?

thanks

[gavinandresen]

Duplicate; hopefully fixed by the "don't use too many file descriptors" fix.

[sipa]

@gavinandresen That's very unlikely on Windows.

[sipa]

@bitcoinstarter You have this problem for more than two weeks now. Does that mean that you fix it, and it re-appears, or after it happened the first time, it just doesn't go away?

[bitcoinstarter]

@sipa @gavinandresen Im still having issues. The problem still persist and I cannot finish synchronizing because of the issue. Below is the latest screenshot of my wallet showing the error.

[bitcoinstarter]

@sipa @gavinandresen no matter what button I choose from the error above, bitcoin-qt.exe has stopped working. This is my problem since I started downloading the client for more than 2 weeks now and I keep having this problem no matter how many times I have re-download the client whether I using the install version or the zip version. same issues.

btw, I using windows 7 Ultimate with 4GB RAM (just for reference).

[sipa]

Is this an error that appears immediately at startup, every time? If so, start with -reindex on the command line, once. That will rebuild the database from scratch.

[bitcoinstarter]

@sipa Yes, that is an error after I fire up the exe. the error appears after a few minutes of initialization.

btw, how do I start wit -reindex on the command line?

Is there a command line version for the wallet? or are you referring to the Windows CMD prompt?

[bitcoinstarter]

@sipa Ok I think youre referring to the Windows CMD prompt so Im giving it a shot. Hope it works and will let you know :)

[sipa]

Did you ever play with testnet before?

[laanwj]

User hasn't reported back after 8 months, likely the -reindex solved the problem.

[partsoven]

-reindex worked for me!