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  • #2348

Closed
Open
Created Aug 24, 2010 by Pascal Cuoq@pascal

Jessie + alt-ergo unsound in presence of division

ID0000571: This issue was created automatically from Mantis Issue 571. Further discussion may take place here.


Id Project Category View Due Date Updated
ID0000571 Frama-C Plug-in > jessie public 2010-08-24 2010-09-29
Reporter pascal Assigned To pascal Resolution no change required
Priority normal Severity major Reproducibility always
Platform - OS - OS Version -
Product Version Frama-C Boron-20100401 Target Version - Fixed in Version -

Description :

A shorter example than the previous ones of functions named "search", where Jessie + Alt-ergo emit an unsound result:

/*@ requires 0 < x <= 1000000000 ; ensures \result / 2 > x; / int function1(int x) { return (2x + 1); }

frama-c -jessie t.c

With Frama-C 20100401, Why 2.26, Alt-ergo 0.91, the post-condition is proved, when it is in fact false for all arguments that satisfy the pre-condition.

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