[cfe-dev] check whether a `case` statement has a `break` statement?

[Marshall Clow]

On Jan 3, 2013, at 12:56 PM, John McCall <rjmccall at apple.com> wrote:

> On Jan 1, 2013, at 6:30 AM, kevinlynx <kevinlynx at gmail.com> wrote:
>> In my parser, I get a `SwitchStmt`, and I can traverse all `case` statements of it. I want to check whether a `case` statement has a `break` statement. But i can not figure it out. Here is my codes:
>> 
>>    for (SwitchCase *c = stmt->getSwitchCaseList(); c != NULL; c = c->getNextSwitchCase()) {
>>            if (isa<CaseStmt>(c)) {
>>                CaseStmt *caseStmt = cast<CaseStmt>(c)
>>                // I do not know how to check `CaseStmt` has a `BreakStmt`
>>            }
>>    }
> 
> Unfortunately, C does not work the way you think it does;  a switch statement
> simply opens a new statement scope, and case statements can be embedded
> at arbitrary positions within those statements.  This really is a control-flow
> analysis, and you need to use the CFG.

Make sure that you have a version of Duff's device in your test matrix for this.

	http://en.wikipedia.org/wiki/Duff's_device

-- Marshall

Marshall Clow     Idio Software   <mailto:mclow.lists at gmail.com>

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