http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56032
--- Comment #1 from Gábor Horváth <xazax.hun at gmail dot com> 2013-01-18
15:01:45 UTC ---
(In reply to comment #0)
> Consider the following code:
>
> // ---- CODE ------
>
> #include <iostream>
> #include <vector>
>
>
> class S {
> public:
> S(const std::vector<char>& v_) : v{v_} {}
> void undefined() {
> std::cout << v.front() << std::endl;
> }
> private:
> const std::vector<char>& v;
> };
>
> int main(){
> std::vector<char> foo {'f', 'a', 'i', 'l'};
> std::cout << foo.front() << std::endl;
> S s{foo};
> s.undefined();
>
> return 0;
> }
>
> // ---- END CODE ------
>
> Compiled with: g++ -std=c++11 main.cpp
>
> s.undefined(); prints invalid characters or crashes the executable.
>
> I think the result of the problem is that, the: v{v_}
> initialization creates a new temporary from the vector that is destroyed after
> the execution leaves the scope of the constructor. ( This would only be the
> intended behaviour in case v would be initialized from initializer list, but
> {v_} is clearly not an initializer list here.)
>
> If I replace the uniform initialization with regular one: v(v_)
> the snippet above works as intended.
>
> The very same snippet does not compile with gcc 4.5.2. Slightly related report
> on that issue: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50025.
>
> I guess the origin of this problem is the incomplete fix of the error above.
- I think the result of the problem is that, the: v{v_}
+ I think the source of the problem is that, the: v{v_}
