http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52460

             Bug #: 52460
           Summary: Misleading error message with templated c++ code
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: pets...@gmail.com


compiling the following:

---8<---8<---8<---8<---
template<typename T>
struct Base
{
        typename T::Type        var;
};
template<typename U>
struct Derived : Base<Derived<U> >
{
        typedef U       Type;
};
void foo()
{
        Derived<int> i;
}
---8<---8<---8<---8<---

gives the error

gcctempl.cpp: In instantiation of ‘struct Base<Derived<int> >’:
gcctempl.cpp:7:8:   required from ‘struct Derived<int>’
gcctempl.cpp:13:15:   required from here
gcctempl.cpp:4:19: error: no type named ‘Type’ in ‘struct Derived<int>’

on all tested gcc versions (4.4, 4.5, 4.6, 4.7). 

There is definitely a type called 'Type' in struct 'Derived', hence the error
message is misleading.

 I'm not sure, the above code is probably ill-formed, because it creates a
circular dependence between the two types, but then, this should be
communicated to the user.

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