[cfe-dev] Template class: initialization list and overloaded functions

[Eli Friedman]

On Tue, Sep 25, 2012 at 10:06 AM, Yin Qiu <qiuyin at gmail.com> wrote:
> Hi,
>
> I noticed some discrepancy when I used libclang to parse a template class definition and a plain non-template one.
>
> Here's the code I fed clang:
> 1 struct A
>   2 {
>   3   A(int);
>   4 };
>   5
>   6 struct  Bar
>   7 {
>   8   Bar(int);
>   9
>  10   void go();
>  11   void go(int);
>  12 };
>  13
>  14 template <class T>
>  15 struct Foo : public Bar
>  16 {
>  17   Foo()
>  18     : Bar(3), a(0)
>  19   {}
>  20
>  21   void baz()
>  22   {
>  23     go();
>  24   }
>  25
>  26   A a;
>  27 };
>  28
>  29 struct Oof : public Bar
>  30 {
>  31   Oof()
>  32     : Bar(3), a(0)
>  33   {}
>  34
>  35   void baz()
>  36   {
>  37     go();
>  38   }
>  39
>  40   A a;
>  41 };
>
> Classes Foo and Oof essentially have the same piece of code except that the former is a class template. clang_visitChildren() shows some differences when parsing the two.
>
> Line 18 vs. Line 32:
> clang reported two UnexposedExpr's at line 18 for those two expressions in the initialization list; whereas it reports two CallExpr's (ctor invocations) at line 32. Can we expose those CallExpr's in the initialization list of a class template as well?
>
> Line 23 vs. Line 37:
> For both classes, a CallExpr and a MemberRefExpr are reported. But for Foo<T>, there is an additional OverloadedDeclRef. Although Bar::go() has two overloads, isn't the function resolved already when we say go() (with void argument) in Foo<T>::baz()?
>
> Did I miss something? Please advise. Thanks!

The API is just reflecting the AST, and trying to aggressively build
more resolved expressions in templates hasn't really been a priority.
If you're interested, patches welcome.

-Eli