The following (toy) program returns different things when linked against libstdc++ and libc++. Is this a bug in libc++ or do I not understand how istream eof() works? I have tried running it using g++ on linux and mac os x and clang on mac os x, with and without -std=c++0x. It was my impression that eof() does not return true until an attempt to read (by get() or something else) actually fails. This is how libstdc++ behaves, but not how libc++ behaves.
#include <iostream>
#include <sstream>
int main() {
std::stringstream s;
s << "a";
std::cout << "EOF? " << (s.eof() ? "T" : "F") << std::endl;
std::cout << "get: " << s.get() << std::endl;
std::cout << "EOF? " << (s.eof() ? "T" : "F") << std::endl;
return 0;
}
Thor:~$ g++ test.cpp
Thor:~$ ./a.out
EOF? F
get: 97
EOF? F
Thor:~$ clang++ -std=c++0x -stdlib=libstdc++ test.cpp
Thor:~$ ./a.out
EOF? F
get: 97
EOF? F
Thor:~$ clang++ -std=c++0x -stdlib=libc++ test.cpp
Thor:~$ ./a.out
EOF? F
get: 97
EOF? T
Thor:~$ clang++ -stdlib=libc++ test.cpp
Thor:~$ ./a.out
EOF? F
get: 97
EOF? T
This was a libc++ bug and has been fixed as Cubbi noted. My bad. Details are here: