[cfe-dev] Missing FieldDecl from macro calls and template arguments

[Adrien Chauve]

On Wed, Jun 15, 2011 at 23:22, Eli Friedman <eli.friedman at gmail.com> wrote:
> On Wed, Jun 15, 2011 at 2:12 PM, Adrien Chauve <adrien.chauve at gmail.com> wrote:
>> On Wed, Jun 15, 2011 at 22:13, Eli Friedman <eli.friedman at gmail.com> wrote:
>>> On Wed, Jun 15, 2011 at 12:58 PM, Adrien Chauve <adrien.chauve at gmail.com> wrote:
>>>> On Wed, Jun 15, 2011 at 21:53, Eli Friedman <eli.friedman at gmail.com> wrote:
>>>>> On Wed, Jun 15, 2011 at 12:27 PM, Adrien Chauve <adrien.chauve at gmail.com> wrote:
>>>>>> Hi,
>>>>>>
>>>>>> I've implemented an ASTConsumer deriving from RecursiveASTVisitor to
>>>>>> rename field names. The consumer implements VisitFieldDecl and
>>>>>> VisitMemberExpr,
>>>>>> but it seems that (at least) two kinds of expressions are not visited.
>>>>>>
>>>>>> 1- First, function arguments that are instance of templates, e.g.:
>>>>>>
>>>>>>    template<typename T>
>>>>>>    struct Foo
>>>>>>    {
>>>>>>        int bar;
>>>>>>
>>>>>>        void copy(const Foo<T>& other) {
>>>>>>            bar = other.bar;  /// bar is visited but not other.bar
>>>>>>        }
>>>>>>    };
>>>>>
>>>>> other.bar in this situation is a CXXDependentScopeMemberExpr, I think...
>>>>
>>>> Thanks I will definitely try that!
>>>>
>>>>>>
>>>>>> If I write the same code but with a non-template Foo struct, all bar
>>>>>> member expressions are visited.
>>>>>>
>>>>>>
>>>>>> 2- Code inside macros, e.g.:
>>>>>>
>>>>>>    Foo foo;
>>>>>>    foo.bar = 2; // bar is visited
>>>>>>    assert(foo.bar == 2); // bar is not visited
>>>>>>
>>>>>> Do I have to get the body of the macro from the Preprocessor and make
>>>>>> something with it?
>>>>>
>>>>> Are you sure you're compiling the given file with asserts enabled?
>>>>> The expression won't show up in the AST if it gets #define'ed out.
>>>>
>>>> I didn't disable asserts with -DNDEBUG, so are they not enabled by default?
>>>
>>> If you didn't define NDEBUG, they should be enabled... not sure what's
>>> going on here.  If the node is getting compiled, it should show up in
>>> the AST, though.  Maybe take a look at the output of -ast-dump?
>>>
>>
>> Thanks for the tip! I'm not really familiar with the output of
>> ast-dump but it looks really nice and assert is definitely there. I'm
>> going to investigate this. Maybe it's because I filtered out the
>> expressions based on their locations. If the expression inside an
>> assert is located in assert.h, that should answer my question. I
>> thought it would be located in the source file where assert is called.
>
> How exactly are you getting the source location?  There are multiple
> locations associated with an expression inside a macro instantiation.
>
> -Eli
>

I use:

     bool VisitMemberExpr(MemberExpr *Node)
     {
         SourceLocation loc = Node->getExprLoc();
        ...
     }

By the way, I didn't get the difference between loc and:

   instanciated_loc = my_src_manager.getInstatiationLoc(loc);


Thanks,
Adrien