CIL's added return masks issues
ID0000685: This issue was created automatically from Mantis Issue 685. Further discussion may take place here.
| Id | Project | Category | View | Due Date | Updated |
|---|---|---|---|---|---|
| ID0000685 | Frama-C | Kernel | public | 2011-01-24 | 2012-09-19 |
| Reporter | virgile | Assigned To | virgile | Resolution | fixed |
| Priority | normal | Severity | feature | Reproducibility | always |
| Platform | - | OS | - | OS Version | - |
| Product Version | Frama-C Carbon-20101202-beta2 | Target Version | - | Fixed in Version | Frama-C Oxygen-20120901 |
Description :
When an execution path in a function may fall through, CIL adds automatically a return statement. If the path is not unfeasible, this would mask an undefined behavior (6.9.1.14), as shown in the example below, where Frama-C would conclude that z is 0, while gcc reports 12:
int x;
int f(void) { x++; if (x<=10) return x-1; }
int main() { x = 11; int y = 42; int z = f(); return z; }