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+---- Thread: Rule 10.6 An expression shall not be assigned to a wider type (/showthread.php?tid=1524)
Rule 10.6 An expression shall not be assigned to a wider type - LordMordac - 27-01-2020
The full rule title is:
Quote:The value of a composite expression shall not be assigned to an object with a wider essential type
I am having a lively debate with my scanner vendor about the quality of their scans. The following example code is generating the commented violation:
[code]
static inline uint32_t bit32 (uint32_t pos)
{
static const uint32_t mask = 31U;
static const uint32_t one = 1U;
// Event misra_c_2012_rule_10_6_violation: Assigning composite expression "1U
Re: Rule 10.6 An expression shall not be assigned to a wider type - misra-c - 03-02-2020
Appendix D.7 gives the essential type of an Shift Expression. It says:
Quote: Shift( > )In this case 1.2 applies and essential type is that of the left hand operand. The essential type of the left hand operand is uint32_t. There is therefore no assignment to a wider essential type and no violation of rule 10.6.
1. If the left hand operand is essentially unsigned then:
1.1 If both operands are integer constant expressions then the essential type of the result is the UTLR of the result;
1.2 Else the essential type of the result is the essential type of the left hand operand
There would have been a violation of rule 10.6 if the code had been written as
[code] 1U