1153415 - TSan: data race db/sqlite3/src/sqlite3.c:50478 walIndexTryHdr

Status: RESOLVED DUPLICATE of bug 1153409

(Toolkit :: Storage, defect)

Description

[Nathan Froyd [:froydnj]]

Attachment: sqlite-walindextryhdr.txt

The attached logfile shows a thread/data race detected by TSan (ThreadSanitizer).

* Specific information about this bug

I think this is related-to and similar-to bug 1153409, which I just filed, but filing it separately, in case the bug is actually with sqlite and needs a separate fix.

If the other bug is fixed with locking on the Gecko side, then this race will probably go away.

* General information about TSan, data races, etc.

Typically, races reported by TSan are not false positives, but it is possible that the race is benign. Even in this case though, we should try to come up with a fix unless this would cause unacceptable performance issues. Also note that seemingly benign races can possibly be harmful (also depending on the compiler and the architecture) [1][2].

If the bug cannot be fixed, then this bug should be used to either make a compile-time annotation for blacklisting or add an entry to the runtime blacklist.

[1] http://software.intel.com/en-us/blogs/2013/01/06/benign-data-races-what-could-possibly-go-wrong
[2] _How to miscompile programs with "benign" data races_: https://www.usenix.org/legacy/events/hotpar11/tech/final_files/Boehm.pdf

Comment 1

[Dan Kennedy]

I think this is the same issue as bug 1153409 as well.