branches: 1.1.4; 1.1.10;
new dlopen tests for libpthread from manu@

libpthread: Link with -Wl,-z,nodelete.

Can't safely unload libpthread because of the interaction with libc
thread stubs.

PR lib/59784: dlopening and dlclosing libpthread is broken

tests/lib/libpthread: Test unloading libpthread after lazy binding.

If you dlopen libpthread and dlclose it again, the thread stubs like
pthread_mutex_lock need to continue working -- a library might have
calls to it in order to support thread-safety for threaded
applications, but that library needs to continue working even in
non-threaded applications after lazy binding of the libpthread symbol
instead of the libc stub.

PR lib/59784: dlopening and dlclosing libpthread is broken

branches: 1.1.4; 1.1.10; 1.1.48;
new dlopen tests for libpthread from manu@

tests/lib/libpthread: Don't abuse xfail.

Use a signal handler to check for SIGABRT, rather than
atf_tc_expect_signal.

xfail is for when there is a bug that we haven't fixed yet and the
test manifests a symptom of that bug -- a list of xfails is a list of
open bugs to be fixed. In this case, we are verifying that
pthread_create _correctly_ raises SIGABRT (or fails with nonzero
return code -- both are acceptable outcomes, really), and there is no
bug here at the moment.

Prompted by (but unrelated to):

PR lib/59784: dlopening and dlclosing libpthread is broken

branches: 1.1.4; 1.1.10; 1.1.48;
new dlopen tests for libpthread from manu@

branches: 1.1.4; 1.1.10;
new dlopen tests for libpthread from manu@

branches: 1.1.4; 1.1.10;
new dlopen tests for libpthread from manu@

branches: 1.1.4; 1.1.10;
new dlopen tests for libpthread from manu@