Re: [csmith-dev] Complicatedness limits might need a little tweaking

[John Regehr <regehr@cs.utah.edu>]

Hi Arthur, you're right.

The solution we've discussed is to put caps on the sizes of more 
constructs.  For example I don't think there's any cap right now on 
total bytes of global variables.  There are limits on function size, 
struct size, array size, and probably a bunch more that I'm forgetting 
about.  Not very elegant, but probably it solves the problem.

Currently our driver scripts (the nasty internal ones, not the ones we 
released) put a timeout on Csmith as well as on everything else :(.

John


On 05/07/2011 01:38 AM, Arthur O'Dwyer wrote:
> For the most part, Csmith generates pretty reasonable medium-sized
> test cases, but it is still possible for it to get carried away. I
> just ran across this unusual case where Csmith 2.0.0 was generating a
> main() function of more than 6000 lines --- thanks to hundreds of
> global variables, a surprising number of which were structs containing
> structs containing structs.
>
> csmith --bitfields --packed-struct -s 785395829>test.c
> wc test.c ; md5sum test.c
>     9043  36116 839634 test.c
> 0814cae40428306881450005f3d23a6c  test.c
>
> I mention it just in case it inspires anyone to figure out a better
> way to limit the worst-case complicatedness of tests.  (Or is limiting
> worst-case complicatedness even a reasonable goal? The occasional
> ridiculously huge test could be seen as a positive thing, by someone
> who's not me.)
>
> -Arthur