[cfe-dev] Finding function declaration?

[Manuel Klimek]

On Sun, May 17, 2015 at 2:09 PM Ben Laurie <benl at google.com> wrote:

> On 16 May 2015 at 16:15, Manuel Klimek <klimek at google.com> wrote:
>
>> On Thu, May 14, 2015 at 3:46 PM Ben Laurie <benl at google.com> wrote:
>>
>>> On 14 May 2015 at 14:43, Manuel Klimek <klimek at google.com> wrote:
>>>
>>>> Ah, wrong parent map :) the ast context has a function to retrieve
>>>> parents that supports crossing into decls. I can look up the details when
>>>> I'm back at a real computer ...
>>>>
>>>
>>> Ah! Thanks.
>>>
>>
>> You can get the ASTContext from the CheckerContext, and then call
>> getParents() on it.
>>
>
> Mildly puzzled why there might be multiple parents, but in any case, it
> works, thanks.
>

Templates.
Template instantiation works in clang by doing tree transformations from
the template pattern to the instantiated template.
To make this scale, non-type-dependent statements are shared between all
instantiations of a template (including its pattern).



>
>
>>
>> Also cc'ing Anna and Jordan, who might have better ideas how to capture
>> context info from a static analyzer check.
>>
>>
>>>
>>>
>>>> BTW do you need the symbolic execution engine for what you want to
>>>> check? If the ast is enough consider using a clang-tidy check, those are a
>>>> bit simpler to write with the ast matchers.
>>>>
>>>
>>> I do need symbolic execution.
>>>
>>>
>>>>
>>>> On Thu, May 14, 2015, 1:20 PM Ben Laurie <benl at google.com> wrote:
>>>>
>>>>> Manuel asked me for more info.
>>>>>
>>>>> Given a checker like this:
>>>>>
>>>>> class MyChecker :
>>>>>     public Checker< check::PreStmt<ReturnStmt> > {
>>>>> public:
>>>>>   void checkPreStmt(const ReturnStmt *RS, CheckerContext &C) const;
>>>>> };
>>>>>
>>>>> void MyChecker::checkPreStmt(const ReturnStmt *RS,
>>>>>      CheckerContext &C) const {
>>>>>   RS->dump();
>>>>>
>>>>>   const Stmt *s = RS;
>>>>>
>>>>>   ParentMap &PM = C.getLocationContext()->getParentMap();
>>>>>
>>>>>   while ((s = PM.getParent(s)) != NULL) {
>>>>>     std::cerr << "------\n";
>>>>>     s->dump();
>>>>>   }
>>>>> }
>>>>>
>>>>> And this as input:
>>>>>
>>>>> int f(void)
>>>>>     {
>>>>>     return 1;
>>>>>     }
>>>>>
>>>>>
>>>>> This is the output:
>>>>>
>>>>> ReturnStmt 0x807cbdda8
>>>>> `-IntegerLiteral 0x807cbdd88 'int' 1
>>>>> ------
>>>>> CompoundStmt 0x807cbddc0
>>>>> `-ReturnStmt 0x807cbdda8
>>>>>   `-IntegerLiteral 0x807cbdd88 'int' 1
>>>>>
>>>>> As you can see, it terminates at the function body, not the
>>>>> declaration.
>>>>>
>>>>>
>>>>> On 14 May 2015 at 07:03, Ben Laurie <benl at google.com> wrote:
>>>>>
>>>>>>
>>>>>>
>>>>>> On 11 May 2015 at 11:20, Manuel Klimek <klimek at google.com> wrote:
>>>>>>
>>>>>>> On Sun, May 10, 2015 at 11:54 PM Nikola Smiljanic <
>>>>>>> popizdeh at gmail.com> wrote:
>>>>>>>
>>>>>>>> I think you'll need to use ParentMap from ASTContext.
>>>>>>>>
>>>>>>>
>>>>>>> Note that the parent-map is lazy-built (that is, the first time you
>>>>>>> get a parent, you build the parent-map for the whole TU), and thus has a
>>>>>>> pretty high cost. Usually we first try to get away with not using it.
>>>>>>>
>>>>>>> Can you give a bit more context on what you're trying to do?
>>>>>>>
>>>>>>
>>>>>> Sorry for delay ... I am trying to label functions to have certain
>>>>>> checks done on their return values if an attribute is set on the function.
>>>>>>
>>>>>> ParentMap appears not to work for this case (it stops finding parents
>>>>>> once you have the function body).
>>>>>>
>>>>>> Currently, the only way I could make this work was to construct a map
>>>>>> of function bodies that have the attribute set in an AST observer, and then
>>>>>> using ParentMap to get back to the body, which is looked up in the map.
>>>>>>
>>>>>> Doesn't seem optimal!
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> On Mon, May 11, 2015 at 4:18 AM, Ben Laurie <benl at google.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> If I have a checker for check::PreStmt<ReturnStmt>, how do I get
>>>>>>>>> from
>>>>>>>>> the ReturnStmt to the function it is part of (I want to check
>>>>>>>>> attributes on that function)?
>>>>>>>>> _______________________________________________
>>>>>>>>> cfe-dev mailing list
>>>>>>>>> cfe-dev at cs.uiuc.edu
>>>>>>>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
>>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> cfe-dev mailing list
>>>>>>>> cfe-dev at cs.uiuc.edu
>>>>>>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
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