Bug#784655: can't rebuild casablanca with newer libstdc++6 (sid)

[Gianfranco Costamagna <costamagnagianfranco@yahoo.it>]

Package: gcc-5
Version: 5.1.1-4
Severity: Serious
Justification: Package rebuild trigger a test failure.



As said, casablanca doesn't pass the testsuite anymore with libstdc++6 library.

I triggered a successful build from Stretch, and upgraded packages until I upgraded libstdc++6

Preparing to unpack .../libstdc++6_5.1.1-4_amd64.deb ...
Unpacking libstdc++6:amd64 (5.1.1-4) over (4.9.2-10) ...


Now I have the testsuite giving some failures:

/casablanca/Release/tests/functional/http/client/connections_and_errors.cpp:94: error: Failure in server_doesnt_exist: CHECK_EQUAL(static_cast<int>(std::errc::host_unreachable), _condFound.value()) where static_cast<int>(std::errc::host_unreachable)=113 and _condFound.value()=0
FAILED
Test case connections_and_errors:server_doesnt_exist FAILED
[...]

and

/casablanca/Release/tests/functional/streams/fstreambuf_tests.cpp:148: error: Failure in OpenForReadDoesntCreateFile1: CHECK_EQUAL(static_cast<int>(std::errc::no_such_file_or_directory), _condFound.value()) where static_cast<int>(std::errc::no_such_file_or_directory)=2 and _condFound.value()=0
FAILED
Test case file_buffer_tests:OpenForReadDoesntCreateFile1 FAILED

(code following from http://anonscm.debian.org/cgit/collab-maint/casablanca.git/tree/Release/tests/functional/streams/fstreambuf_tests.cpp)
TEST(OpenForReadDoesntCreateFile1)
{
utility::string_t fname = U("OpenForReadDoesntCreateFile1.txt");
VERIFY_THROWS_SYSTEM_ERROR(OPEN_R<char>(fname).get(), std::errc::no_such_file_or_directory);
std::ifstream is;
VERIFY_IS_NULL(is.rdbuf()->open(fname.c_str(), std::ios::in));
}

any idea for the regression?

thanks,

Gianfranco