Possible benchmark performance regression and async benchmark segfaults

[Ingramz]

I noticed an issue while trying to run benchmarks:
v5.1.2 with 898fc90 applied:

> .\node_modules\.bin\coffee .\benchmark\benchmark.coffee
oneline.js
sync:  149652 matches in 260ms
large.js
sync:  14594 matches in 69ms
async: 14594 matches in 795ms
> echo $LASTEXITCODE
0

v6.0.0 and up:

> .\node_modules\.bin\coffee .\benchmark\benchmark.coffee
OR (depending on version)
> node .\benchmark\benchmark.js
oneline.js
sync:  149652 matches in 21987ms
large.js
sync:  14594 matches in 243ms
> echo $LASTEXITCODE
-1073741819

Sometimes async gets displayed as well and everything looks "normal":

> .\node_modules\.bin\coffee .\benchmark\benchmark.coffee
oneline.js
sync:  149652 matches in 22129ms
large.js
sync:  14594 matches in 245ms
async: 14595 matches in 740ms
> echo $LASTEXITCODE
0

Same result on both OS X and Windows.

Whether the benchmark results are meaningful, I cannot tell, however I couldn't figure out what exactly causes the segfaults in async benchmark.

Pinging @alexandrudima @zcbenz @maxbrunsfeld

[michaelb87]

Hi,
I noticed those segfaults on a production app based on load.
When we were debugging this using gdb, we found it's due to a race condition of the async worker.

Unfortunately I don't have a fix, since we decided to just replace the library.

[Aerijo]

The shared pointer holding the OnigResult appears to be the cause of the segfaults when it gets destructed (coupled with thread race stuff). Converting it to a regular pointer and managing memory manually seems to fix it. I'm not sure why the shared pointer is having issues though.

[michaelb87]

@Aerijo out of curiosity I'm revisiting this from time to time.
Found the pull request where they replaced the regular pointer with a shared pointer: https://github.com/atom/node-oniguruma/pull/6/files
Seems they fixed one issue, but might have introduced another one. Or the async stuff was added later, not sure.

I'm not a C++ dev, but might give it a shot on fixing this. If anyone has recommendations on how to approach the issue, I'm more than happy for input.