...
| Code Block | ||||
|---|---|---|---|---|
| ||||
int value;
if (scanf("%d", &value) == 1) {
if (value % 2 != 0) {
/* Take action if value is odd */
}
}
|
Compliant Solution
Using bitwise operators is safe on unsigned integers:
| Code Block | ||||
|---|---|---|---|---|
| ||||
unsigned int value;
if (scanf("%u", &value) == 1) {
if (value & 0x1 != 0) {
/* Take action if value is odd */
}
}
|
Risk Assessment
Incorrect assumptions about integer representation can lead to execution of unintended code branches and other unexpected behavior.
Recommendation | Severity | Likelihood | Remediation Cost | Priority | Level |
|---|---|---|---|---|---|
INT16-C | Medium | Unlikely | High | P2 | L3 |
Automated Detection
Tool | Version | Checker | Description | ||||||
| Astrée |
| bitop-type | Partially checked | ||||||
| Helix QAC |
| C2940, C2945 DF2941, DF2942, DF2943, DF2946, DF2947, DF2948 | |||||||
| LDRA tool suite |
| 50 S, 120 S | Partially Implemented | ||||||
| Parasoft C/C++test |
|
|
|
2940, 2941, 2942, 2943, 2945, 2946, 2947, 2948
...
| CERT_C-INT16-a | Bitwise operators shall only be applied to operands of unsigned underlying type | ||||||||
| PC-lint Plus |
| 502, 2704, 9088 | Partially supported: reports bitwise not of signed quantity, declaration of named signed single-bit bitfields, and negation of the minimum negative integer | ||||||
| RuleChecker |
| bitop-type | Partially checked |
...