`RULE-18-1`: Picky about how pointers are tracked, doesn't consider derefs before 1 from end, or array-to-pointer conversions
Nobody has claimed this yet.
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 35/100
Research direction
Locate the query implementations for RULE-18-1 and M5-0-16, then compare how they track pointer creation, array-to-pointer conversions, direct address expressions, and one-past-the-end accesses. Done means the examples distinguish valid one-past pointers from invalid dereferences or indexing and report each non-compliant case without the listed false negatives.
Written by the indexing model from the issue text.
Description
Affected rules
RULE-18-1M5-0-16
Description
The query expects that as pointers are made they are assigned to variables, and assumes that pointers into arrays always use ArrayExpr (eg x[y]). It also allows dereferencing or indexing past 1 of an array -- its OK to make a pointer to 1 past the array, but dereferencing is not defined.
Example
void example_function() {
int x[10];
int *p1 = &x[12]; // NON_COMPLIANT
f(p1);
int *p2 = x + 12; // NON_COMPLIANT[FALSE_NEGATIVE]
f(&x[12]); // NON_COMPLIANT[FALSE_NEGATIVE]
int *p3 = &x[10]; // COMPLIANT
*p3; // NON_COMPLIANT[FALSE_NEGATIVE]
x[10]; // NON_COMPLIANT[FALSE_NEGATIVE] - at least for MISRA-C
}
- Dominant language
- CodeQL
- Stars
- 227
- Forks
- 82
- Avg merge
- 6d 7h
- Merged PRs (30d)
- 9
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
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