Lowercase letter l (ell) can easily be confused with the digit 1 (one). This can be particularly confusing when indicating that an integer literal constant is a long value. This recommendation is similar to DCL02-C. Use visually distinct identifiers.
Likewise, you should use uppercase LL rather than lowercase ll when indicating that an integer literal constant is a long long value.
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Tool | Version | Checker | Description | ||||||
|---|---|---|---|---|---|---|---|---|---|
| ltrlsynt | Fully implemented | |||||||
| PRQA QA·CQA-C |
| Fully implemented |
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CERT C++ Secure Coding Standard: DCL16-CPP. Use 'L', not 'l', to indicate a long value
Bibliography
Lockheed Martin 2005 AV Rule 14, Literal suffixes shall use uppercase rather than lowercase letters.
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