[Bug libstdc++/84367] [C++11] std::ostringstream stops inserting after multiple call to move assignment operator

[ftingaud at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84367

--- Comment #2 from Frederic Tingaud <ftingaud at gmail dot com> ---
I reran the test with GCC 7.3, but got the same error:

#include <sstream>
#include <cassert>
#include <iostream>

int test()
{
   std::ostringstream oss;
   std::cerr << "\nRunning with GCC v" << __GNUC__ << "." << __GNUC_MINOR__ <<
"." << __GNUC_PATCHLEVEL__ << " - libc++=" << __GLIBCXX__ << std::endl;
   for (int i = 0; i < 100; ++i) {
      oss << "abc";
      std::cerr << i << " ";
      assert(oss.str() == "abc");
      oss = std::ostringstream();
   }
   return 0;
}

output:

Running with GCC v7.3.0 - libc++=20180125
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 
file.cpp:13: int test(): Assertion `oss.str() == "abc"' failed.
Aborted