c++ template seems to break access specifiers
The following code doesn't compile for obvious reasons, namely that Foo is trying to access a private member of Bar. However if you uncomment/comment the lines marked, making Foo a template, it does compile and outputs 42. What am I missing here? Why does this work? Seems to me it shouldn't.
Thanks for your help.
#include <iostream>
class Bar {
private:
static const int x = 42;
};
//template <int> // uncomment me
struc开发者_运维问答t Foo {
static const int i = Bar::x;
};
int main(int argc, char* argv[]) {
std::cout << Foo::i << std::endl; // comment me
//std::cout << Foo<0>::i << std::endl; // uncomment me
}
If you are seeing this behavior, it is a compiler bug.
Both Comeau Online and Visual C++ 2010 reject the code as invalid because Bar::x
is inaccessible. g++ 4.1.2 incorrectly accepts the invalid code (someone would need to test with a later version to see if it's been fixed; that's the only version I have on this laptop).
This seems like GCC bug 40843. It is listed as UNCONFIRMED, but I can reproduce it on g++ (Ubuntu 4.4.3-4ubuntu5) 4.4.3
as well.
VisualStudio 2010 said "error C2248: 'Bar::x' [...] As the plateform was not speciifed, I have assessed that the assumption is false almost on Windows VC9.
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