Previously tsan modelled dup2(oldfd, newfd) as write on newfd.
We hit several cases where the write lead to false positives:
1. Some software dups a closed pipe in place of a socket before closing
the socket (to prevent races actually).
2. Some daemons dup /dev/null in place of stdin/stdout.
On the other hand we have not seen cases when write here catches real bugs.
So model dup2 as read on newfd instead.
llvm-svn: 240687
The new storage (MetaMap) is based on direct shadow (instead of a hashmap + per-block lists).
This solves a number of problems:
- eliminates quadratic behaviour in SyncTab::GetAndLock (https://code.google.com/p/thread-sanitizer/issues/detail?id=26)
- eliminates contention in SyncTab
- eliminates contention in internal allocator during allocation of sync objects
- removes a bunch of ad-hoc code in java interface
- reduces java shadow from 2x to 1/2x
- allows to memorize heap block meta info for Java and Go
- allows to cleanup sync object meta info for Go
- which in turn enabled deadlock detector for Go
llvm-svn: 209810
some tests test libc/filesystem error handling paths (e.g. close(INT_MAX)),
currently such tests fail
with this change they work as expected
llvm-svn: 193400
Dmitry Vyukov