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+---- Thread: MISRA C++ 9.6.2 (/showthread.php?tid=1695)
MISRA C++ 9.6.2 - gdavis - 06-07-2024
Hello,
My question is about the third example for MISRA C++ 2023 Rule 9.6.2: "A goto statement shall reference a label in a surrounding block".
void f3(int32_t i, int32_t x, int32_t y)
{
switch( i )
{ // statement A
case 0:
if ( x < y )
goto L3; // Non-compliant
break;
case 1:
L3:
break;
}
}
I am not sure why this is non-compliant. In terms of the amplification of the rule, "A goto statement shall be enclosed in a statement that directly encloses its reference label", statement A is the compound statement as shown above. I believe the goto statement is enclosed within statement A, and statement A directly-encloses the reference label (L3).
The MISRA C 2012 and MISRA C 2023 versions of the equivalent rule 15.3 provide a different amplification that directly addresses this: "A switch-clause that does not consist of a compound statement is treated as if it were a block"
Please let me know what you think. Thank you.
RE: MISRA C++ 9.6.2 - misra cpp - 12-07-2024
You're right that the goto is enclosed by the IF, the labelled statement case 0 and the switch body, however L3 is only directly enclosed by the labelled statement case 1 - so is not allowed by this rule.
In addition, the label L3 is part of a switch label group, which is not allowed by 9.4.2 amplification item 3.