Rule 5-0-3 false positive warning

Rule 5-0-3 false positive warning - Printable Version

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Rule 5-0-3 false positive warning - mikearmagedon - 04-04-2017

My static analyzer is throwing the following warning:

Quote:MCPP Rule 5-0-3: This complex expression is implicitly converted to a different essential type

for the following code:

Code:
void func(const uint32_t arg)

{

    //32U has underlying type uint8_t

    const uint32_t u32a = arg % 32U; //warning issued in this line

    const uint32_t u32b = static_cast(arg % 32U); //compliant

}

I think this warning may be a false positive because, despite the 32U having a uint8_t underlying type, the expression should take the underlying type of the larger type, in this case the uint32_t, thus making the need for the static_cast unnecessary.

Do you agree this is a false positive? Or am I looking at it all wrong?

Re: Rule 5-0-3 false positive warning - misra cpp - 10-07-2017

Your example code is compliant - contact your static analysis vendor