Possibility of integer overflow in JfrThreadSampler::run()

[Yasumasa Suenaga]

Hi all,

I posted this issue in May 2018 [1].
It still occurs in current jdk/jdk when it was build by GCC 8.

We can avoid it with -fno-strict-overflow GCC option. So I propose to add it
to JvmOverrideFiles.gmk:

  http://cr.openjdk.java.net/~ysuenaga/jfr-integer-overflow/webrev.1/

JDK-8147466 has been fixed with similar change for jdk7u [2].

What do you think?
I will file it to JBS if it is accepted.


Thanks,

Yasumasa

[1] https://mail.openjdk.java.net/pipermail/hotspot-jfr-dev/2018-May/000047.html
[2] http://hg.openjdk.java.net/jdk7u/jdk7u/jdk/rev/35dcc0db31dc