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

[Adrien Chauve]

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.

Thanks,
Adrien

> -Eli
>