This is a draft version of a MISRA C++ 202x rule proposed for public review.
MISRA Rule 9.6.3
Category: Required
Analysis Type: Decidable,Single Translation Unit
Rationale
The unconstrained use of goto can lead to programs that are extremely difficult to comprehend and analyse. However, flags may need to
be introduced to give the required control flow when it is not used, with the possibility that the flags may themselves make the code less transparent
than if goto were used. The restricted use of goto is therefore allowed where that use will not lead to semantics contrary
to developer expectations.
This rule prohibits the use of back jumps as they can be used to introduce iteration without using the well-defined iteration statements supplied
by the language.
Note: the C++ Standard places restrictions on the uses of forward jumps. For example, it is not permitted to jump from a point
where a local variable with initialization is not in scope to a point where it is in scope.
Example
void f()
{
int32_t x = 0;
L1:
if ( x == 10 )
{
goto L2; // Compliant
}
else
{
++x;
goto L1; // Non-compliant
}
L2:
return;
}
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