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From: "schaub.johannes at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/49051] New: Doesn't SFINAE away an invalid substitution into toplevel parameter type "T[N]"
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49051

           Summary: Doesn't SFINAE away an invalid substitution into
                    toplevel parameter type "T[N]"
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: schaub.johannes@googlemail.com


GCC incorrectly fails to compile this code

template<typename T> void f(T[1]) = delete; 
template<typename T> void f(...); 
int main() { f<void>(0); }

The substitution into "T" should fail, because "T[1]" is an invalid type, and
hence the call should use the second template. 

Note that I think it's unspecified in the spec what happens when we tweak
things as follows

template<typename T> void f(T[1]) = delete; 
template<typename T> void f(T*);
template<typename T> void f(...); 
int main() { f<void>(0); }

The first two templates are equivalent, but behave different during
substitution. The spec doesn't specify what the outcome of this is, I think.