Re: temporaries and const&
On Apr 30, 2:21 pm, "Alf P. Steinbach" <a...@start.no> wrote:
* dragoncoder:
Thanks for the response. In the same context, does this code invoke
undefined behaviour ?
#include <iostream>
template <class T1, class T2>
const T1& max ( const T1& a, const T2& b )
{
return ( a > b ) ? a : b;
}
int main() {
int i = 20; double d = 40;
std::cout << max ( i, d ) << std::endl;
return 0;
}
Yep. It would be less clear-cut if both arguments were "int const&".
I'd have to read the standard's fine print about the ?:-operator to
figure that out, but I think that when the types are identical reference
types it can produce a reference result, thus no UB in that case.
I am a bit confused now. Are you saying it is a case of UB because the
temporary is being accessed after the function call ? That being the
case a simple function like below will also invoke UB ? Am I right ?
const int& bar ( ) { return 10; }
std::cout << bar() << std::endl;
Please enlighten me. Thanks again.
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