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From: "mkp76 at wp dot pl" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/51426] New: explicit instantiation declaration without definition
Date: Mon, 05 Dec 2011 18:41:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51426

             Bug #: 51426
           Summary: explicit instantiation declaration without definition
    Classification: Unclassified
           Product: gcc
           Version: 4.6.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mkp76@wp.pl


The below code can be compiled (with -std=C++0x option).

--------------------------
template <typename T>
struct A { };

extern template
struct A<int>;

int main()
{
    A<int> a;
}
--------------------------

According to C++11 standard (14.7 paragraph 5) it shouldn't
"an explicit instantiation definition shall appear at most once in a program"

I was trying to test 'extern templates' based on Bjarne Stroustrup's page:
http://www2.research.att.com/~bs/C++0xFAQ.html#extern-templates

Regards,
Marcin