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Re: [csmith-dev] version 7d6fae9: x = x = .;

On Sun, Jul 24, 2011 at 11:32 PM, Xuejun Yang <jxyang@cs.utah.edu> wrote:
I believe this problem is fixed in commit cc2104.

I am sorry that I can't confirm that yet, but the reason why I can't
is one you will like: previously, my test script would fill
its working directory of problematic programs in a few seconds,
now it fills its working directory of programs that I believe to
be non-problematic. That is, it finds precision bugs in Frama-C.

Just to be clear, we all agree that the following line is ok, right?

x = f(x=2);

Because Csmith generates them and the development version
of Frama-C warns (I believe wrongly) on them.

A meta-remark for the philosophers: are we all spending a
lot of time for not much here? One of the discussions at
the SCAM conference that I like for its discussions was
whether we shouldn't all be working on Java rather than
previous generation, difficult languages that will be obsolete
before we produce satisfactory analyses for them.
I do not fully agree with that point of view: first, Java has
its own, different, difficulties. Second, many static analysis
techniques are more mature than the statement implies,
and can be made to work now in some contexts, so
it's a good idea to work on whatever languages are used now.

Still, the existing C code whose correctness matters
does not do "x = f (x=2);". Perhaps that part of the
C language should be considered like the obsolete,
difficult language unworthy of working on.

Anyway, everyone has to have a hobby. This one is
as good as many.

Congratulations on the quick fix, we'll try to match
it with a precise analyzer as soon as we can.