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+---- Thread: M5-0-20 clarification (/showthread.php?tid=1640)
M5-0-20 clarification - rt1980 - 25-01-2023
Hi All,
Rule 5-0-20 states that "Non-constant operands to a binary bitwise operator shall have the same underlying type." seems to make sense but my colleagues and I are bit unsure why the non-constant qualifier?
Consider the following example. It's not clear to us why the first should be allowed if the second is not.
Code:
int foo(int i) {
const unsigned char mask = ~(0x10);
return i ^ mask; // compliant: mask is const
}
int foo(int i) {
unsigned char mask = ~(0x10);
return i ^ mask; // non-compliant: mask is not const and a different type than i
}Thanks for your help!
Rafe
RE: M5-0-20 clarification - misra cpp - 10-11-2023
The intent of the rule was to apply to expressions that could be evaluated at compile-time.
Hence both your examples are non-compliant.
This will be addressed in the new version - due imminently.