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| CERT C++ Secure Coding Standard | STR34-CPP. Cast characters to unsigned types before converting to larger integer sizes |
| ISO/IEC TR TS 17961 (Draft) | Conversion of signed characters to wider integer types before a check for EOF [signconv] |
| MISRA-C | Rule 6.1 (required): The plain char type shall be used only for the storage and use of character values |
| MITRE CWE | CWE-704, Incorrect type conversion or cast |
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