I don't have access to VC++ 7.1 right now, so I can't find the whole problem you're having, but I have one comment: the uses of typename before is_arithmetic and is_object are unnecessary, since the types you're accessing are not members. I don't know if it will solve your ICE problem, but try removing those uses of typename. Otherwise, try using enable_if_c and adding ::value after the conditions (but still without a typename inside the condition for enable_if_c). Jeremiah Willcock On Sat, 18 Dec 2004, Agoston Bejo wrote:

Has anyone succeeded in specializing class templates with enable_if under VC++7.1? I have created the simplest example possible and cannot imagine how I could rewrite so that no Internal Compiler Error occurs. I have tried with both the boost 1.31 and 1.32 headers, with no difference.

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#include <iostream> #include #include

using namespace std; using namespace boost;

template struct A { enum { X = 0 }; };

template<typename T> struct A::type> { enum { X = 1 }; };

template<typename T> struct A::type> { enum { X = 2 }; };

struct B {};

int _tmain(int argc, _TCHAR* argv[]) { // cout << is_arithmetic<double>::value << endl; typedef A<float> Afloat; cout << Afloat::X << endl; // Internal Compiler Error cout << A<int>::X << endl; cout << A<B>::X << endl; return 0; }

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Agoston Bejo wrote:

Has anyone succeeded in specializing class templates with enable_if under VC++7.1?

Yes, I do it once in a while. I'd do it more if I didn't have to support old compilers.

I have created the simplest example possible and cannot imagine how I could rewrite so that no Internal Compiler Error occurs.

Obviously the ICE is a microsoft bug. It occurs in VC8.0 beta, too, so it should be reported. However, the real problem is that int and float both satisfy is_object and is_arithmetic, so two partial specializations match equally well. Here's the output from como 4.3.3: "C:\DOCUME~1\turkanis\Home\C++\overloadvc71\example.cpp", line 31: error: more than one partial specialization matches the template argument list of class "A" "A::type>" "A::type>" cout << Afloat::X << endl; // Internal Compiler Error ^ "C:\DOCUME~1\turkanis\Home\C++\overloadvc71\example.cpp", line 32: error: more than one partial specialization matches the template argument list of class "A" "A::type>" "A::type>" cout << A<int>::X << endl; Jonathan