On Darwin we have two external symbolizers: atos and llvm-symbolizer.
atos was changed to use posix_spawn (instead of fork+execv) in a
previous commit [1]. Let's use posix_spawn for llvm-symbolizer as well.
Our hope is that eventually we can transition to posix_spawn on other
platforms too.
[1] 399408a92f
llvm-svn: 369021
On Darwin, we currently use forkpty to communicate with the "atos"
symbolizer. There are several problems that fork[pty] has, e.g. that
after fork, interceptors are still active and this sometimes causes
crashes or hangs. This is especially problematic for TSan, which uses
interceptors for OS-provided locks and mutexes, and even Libc functions
use those.
This patch replaces forkpty with posix_spawn on Darwin. Since
posix_spawn doesn't fork (at least on Darwin), the interceptors are not
a problem. Another benefit is that we'll handle post-fork failures (e.g.
sandbox disallows "exec") gracefully now.
Related revisions and previous attempts that were blocked by or had to
be revered due to test failures:
https://reviews.llvm.org/D48451https://reviews.llvm.org/D40032
Reviewed By: kubamracek
Differential Revision: https://reviews.llvm.org/D65253
llvm-svn: 368947
See https://reviews.llvm.org/D58620 for discussion, and for the commands
I ran. In addition I also ran
for f in $(svn diff | diffstat | grep .cc | cut -f 2 -d ' '); do rg $f . ; done
and manually updated (many) references to renamed files found by that.
llvm-svn: 367463
Julian Lettner