[Bug c++/11858] New: Name lookup error ignored when instantiated from expression within sizeof() in template function parameter

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11858

           Summary: Name lookup error ignored when instantiated from
                    expression within sizeof() in template function
                    parameter
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gccbugs at contacts dot eelis dot net
                CC: gcc-bugs at gcc dot gnu dot org

GCC accepts the following invalid code:

template <typename T> struct S { static typename T::x f (); };
template <class T> int f (int [sizeof(T::f())]);
int const i = f<S<int> >(0);

Comeau (4.3.3 beta) does the detect the error, and says:

line 1: error: name followed by "::" must be a class or namespace name
template <typename T> struct S { static typename T::x f (); };
                                                   ^
detected during:
 instantiation of class "S<T> [with T=int]" at line 2
 instantiation of "f" based on template argument <S<int>> at line 3

I'm using GCC version 3.4 20030723.