runtime/race: missed race on []byte

[AlekSi]

What steps will reproduce the problem?
http://play.golang.org/p/3A5HyhWX3m (see comment on top)

What is the expected output?
Race detector warnings.

What do you see instead?
No warnings.

Which compiler are you using (5g, 6g, 8g, gccgo)?
6g

Which operating system are you using?
Mac OS X 10.8.3

Which version are you using?  (run 'go version')
Both 1.1 and current tip.

[dvyukov]

Comment 1:

I suspect it's because race detector does not understand that syscall.Read() writes to
the memory.

Labels changed: added racedetector.

Owner changed to @dvyukov.

Status changed to Accepted.

[gopherbot]

Comment 2 by Lytvynov.A.V:

This might probably be a different but similar issue:
http://play.golang.org/p/WT5NUDVs_r
bytes.Buffer does not use syscall.Read() but it uses builtin copy (so I assume it's some
syscall anyways).
Interestingly, with smaller buffer (100, for example) it does detect the race.

[dvyukov]

Comment 3:

And this is because 200%4==0

[dvyukov]

Comment 4:

@Lytvynov.A.V
yes, this is a different issue, I've filed:
https://golang.org/issue/5654

[dvyukov]

Comment 5:

This issue was closed by revision fc80764.

Status changed to Fixed.