alias between int* and uint* handled incorrectly
ID0000829: This issue was created automatically from Mantis Issue 829. Further discussion may take place here.
|ID0000829||Frama-C||Plug-in > jessie||public||2011-05-18||2011-05-24|
|Product Version||Frama-C Carbon-20110201||Target Version||-||Fixed in Version||-|
The manual "jessie-tutorial-Carbon-beta.pdf" allows casts between pointer types (p.22). However, in the attached program, the property "*x == \old(*x)" of the function ftest() can be verified under SeparationPolicy(none), although ftest() modifies *x via its (possible) alias *y. A reason for this behavior is that x and y point to different types, viz. int and uint (if y is made an int, too, the bug vanishes).
As a consequence, "p == \old(p)" can be proven for main(), although running the program reveals that p changes from 0 to 123. A side remark: type incompatibility uint* vs. int* seems to be unchecked in the initialization in line 14; no cast was needed there.