[Bug libstdc++/67578] std::random_device::entropy() always returns 0

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67578

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Tue May 23 16:11:57 2017
New Revision: 248374

URL: https://gcc.gnu.org/viewcvs?rev=248374&root=gcc&view=rev
Log:
PR libstdc++/67578 Implement non-trivial std::random_device::entropy

2017-05-23  Xi Ruoyao  <ryxi@stu.xidian.edu.cn>
            Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/67578
        * acinclude.m4: Bump libtool_VERSION.
        * config/abi/pre/gnu.ver: Create GLIBCXX_3.4.24 with new symbol.
        * config.h.in: Regenerate.
        * configure: Regenerate.
        * configure.ac: Add test for <linux/random.h>.
        * doc/xml/manual/abi.xml: Document new library version.
        * include/bits/random.h (random_device::entropy)
        [_GLIBCXX_USE_RANDOM_TR1]: Add call to new _M_getentropy member.
        (random_device::_M_getentropy): Declare.
        * src/c++11/random.cc (random_device::_M_getentropy): Define.
        * testsuite/util/testsuite_abi.cc: Add GLIBCXX_3.4.24 to known
        versions, and make it the latest version.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/acinclude.m4
    trunk/libstdc++-v3/config.h.in
    trunk/libstdc++-v3/config/abi/pre/gnu.ver
    trunk/libstdc++-v3/configure
    trunk/libstdc++-v3/configure.ac
    trunk/libstdc++-v3/doc/xml/manual/abi.xml
    trunk/libstdc++-v3/include/bits/random.h
    trunk/libstdc++-v3/src/c++11/random.cc
    trunk/libstdc++-v3/testsuite/util/testsuite_abi.cc