[PATCH v2 0/9] Separate shrink-wrapping

Bernd Schmidt bschmidt@redhat.com
Fri Aug 26 13:55:00 GMT 2016


On 08/26/2016 03:48 PM, David Malcolm wrote:
> I'm nervous about the build_random_cfg function: randomness in
> selftests seems like a double-edged sword.  On the one hand, we can use
> it to fuzz-test an optimization to rapidly gain a lot of coverage.  On
> the other hand, does every host generate the same sequence of values?
> Presumably we want everyone to be effectively running the same
> selftests.

I intended to put a srandom call in there at the start but forgot. One 
could argue that there's value in having different tests on different 
hosts, as long as they are stable between runs, but...

> Maybe there's a need for some kind of selftest::rng class here?

That might be a good idea too.

> On a unrelated note, should the various vfunc implementations be marked
> with "FINAL OVERRIDE" (from coretypes.h), so that the compiler has a
> better chance of devirtualizing them in a release build?

Wasn't aware of that - will have a look.

Maybe we could also use a long-running "-fselftest=extensive" for 
stress-testing algorithms such as this (increasing the number of random 
cfgs it tries)?


Bernd



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