--- layout: fc_discuss_archives title: Message 54 from Frama-C-discuss on April 2013 ---
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[Frama-c-discuss] New Frama-C version: Fluorine



The fact that a prover "suddenly" proves everything when before it 
wasn't, may be the sign of an inconsistency in the context. A good 
practice in such a case is to try to insert a few "smoke detector" in 
your code. Typically, you may try to insert

//@ assert \false;

right before the return instruction. If this assertion is also proved, 
then you have found an inconsistency.

Hope this helps,

- Claude

On 04/19/2013 09:34 PM, Cristiano Sousa wrote:
> Ok, something really weird is happening. With z3 i'm able to prove
> everything that i previously was not able. Either the POs always have
> been correct and WP was limited, or why/z3 is experiencing some strange
> behavior. I believe it's the latter
>
> On a side note related to the new memory model. What implications arise
> from using the unsafe casts option?
>
>
> 2013/4/19 Cristiano Sousa <cristiano.sousa126 at gmail.com
> <mailto:cristiano.sousa126 at gmail.com>>
>
>     Thanks,
>
>     the patch file however tries to patch various files in src/wp/test
>     that do not exists (at least in the public release). Removing that
>     solves the problem and why works again with the following warnings:
>
>     File "/Users/xxxx/.frama-c-wp/typed/Axiomatic.why", line 16,
>     characters 8-11: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 22, characters 6-9: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 65, characters 6-9: unused variable x_1
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 64, characters 6-9: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 108, characters 6-9: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 141, characters 6-9: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 186, characters 6-9: unused variable x_0
>     File
>     "/Users/xxxx/.frama-c-wp/project.session/../typed/strlen_Why3_ide.why",
>     line 223, characters 6-9: unused variable x_0
>
>     http://pastebin.com/ckjLNaGZ
>
>     curiously z3 is able to successfully prove everything in the
>     original code (without the addition of BASE and END)
>
>
>     2013/4/19 Lo?c Correnson <loic.correnson at cea.fr
>     <mailto:loic.correnson at cea.fr>>
>
>         Missing an include.
>
>
>
>         Le 19 avr. 2013 ? 16:41, Cristiano Sousa a ?crit :
>
>>         Hi,
>>
>>
>>         2013/4/19 Lo?c Correnson <loic.correnson at cea.fr
>>         <mailto:loic.correnson at cea.fr>>
>>
>>             Thanks for the bug report.
>>             Current status :
>>
>>             1. pointer comparison is actually missing in Why3 resources ;
>>             2. pointer difference is incorrectly translated in WP ;
>>
>>
>>         Even with the patch applied, is why3 still not supposed to work?
>>
>>         Error while reading file '../typed/strlen_Why3_ide.why': File
>>         "/usr/local/share/frama-c/wp/memory.why", line 36, characters
>>         36-40: Unbound symbol 'bool'
>>
>>         --
>>         Regards,
>>         Cristiano Sousa
>>         _______________________________________________
>>         Frama-c-discuss mailing list
>>         Frama-c-discuss at lists.gforge.inria.fr
>>         <mailto:Frama-c-discuss at lists.gforge.inria.fr>
>>         http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/frama-c-discuss
>
>
>         _______________________________________________
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>
>
>
>
>     --
>     Cumprimentos,
>     Cristiano Sousa
>
>
>
>
> --
> Cumprimentos,
> Cristiano Sousa
>
>
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