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Re: [csmith-bugs] csmith hang



Hi Ahmed,

Nice to see you here :)

Although Csmith often runs pretty quickly, there are, buried within it, some algorithms that probably scale cubically or worse with respect to function size, number of pointer variables, and stuff like that. So, as you have noticed, it sometimes runs for a long long time.
My position would be that we should definitely fix real termination 
errors (actual infinite loops) but that fixing the "very long run-time" 
problem is probably impractical given the level of resources that we 
have.  Unfortunately, telling these cases apart is hard!  And probably 
not worth it.
On the bright side, we have done some looking into the problem of 
teaching a random testcase generator how to "escape" from the program it 
is generating -- while still producing a valid test case -- when some 
resource budget (time, memory, or whatever) is exceeded.  It appears 
that this is feasible, but we're not going to try it out in Csmith.
John




On 10/18/11 11:56 PM, Ahmed Charles wrote:
The following seed seems to cause csmith (github version) to hang. If
these hangs aren't interesting, just let me know.

/*
  * This is a RANDOMLY GENERATED PROGRAM.
  *
  * Generator: csmith 2.1.0
  * Git version: a5e5fd1
  * Options:   --bitfields --packed-struct --output test4.c
  * Seed:      386941147
  */

#include "csmith.h"


static long __undefined;