Fix GCC atomic implementation in C++03
Pull in r250802 from upstream libc++ trunk (by Eric Fiselier):
Detect relaxed constexpr rules for gcc versions
Pull in r255585 from upstream libc++ trunk (by Eric Fiselier):
Fix various GCC mis-configurations for newer versions.
This patch goes through and enables C++11 and C++14 features for newer GCC's.
The main changes are:
1. Turn on variable templates. (Uses __cpp_variable_templates)
2. Assert atomic<Tp> is trivially copyable (Uses _GNUC_VER >= 501).
3. Turn on trailing return support for GCC. (Uses _GNUC_VER >= 404)
4. XFAIL void_t test for GCC 5.1 and 5.2. Fixed in GCC 6.
Together, these should fix building clang 3.8.0 as part of building
world with recent versions of gcc (e.g. the devel/*-xtoolchain-gcc
ports).
C++14 support[1], adds more C++1z features[2], and fixes the following
LWG issues[3]:
1450: Contradiction in regex_constants
2003: String exception inconsistency in erase.
2075: Progress guarantees, lock-free property, and scheduling
assumptions
2104: unique_lock move-assignment should not be noexcept
2112: User-defined classes that cannot be derived from
2132: std::function ambiguity
2135: Unclear requirement for exceptions thrown in
condition_variable::wait()
2142: packaged_task::operator() synchronization too broad?
2182: Container::[const_]reference types are misleadingly specified
2186: Incomplete action on async/launch::deferred
2188: Reverse iterator does not fully support targets that overload
operator&
2193: Default constructors for standard library containers are explicit
2205: Problematic postconditions of regex_match and regex_search
2213: Return value of std::regex_replace
2240: Probable misuse of term "function scope" in [thread.condition]
2252: Strong guarantee on vector::push_back() still broken with C++11?
2257: Simplify container requirements with the new algorithms
2258: a.erase(q1, q2) unable to directly return q2
2263: Comparing iterators and allocator pointers with different
const-character
2268: Setting a default argument in the declaration of a member
function assign of std::basic_string
2271: regex_traits::lookup_classname specification unclear
2272: quoted should use char_traits::eq for character comparison
2278: User-defined literals for Standard Library types
2280: begin / end for arrays should be constexpr and noexcept
2285: make_reverse_iterator
2288: Inconsistent requirements for shared mutexes
2291: std::hash is vulnerable to collision DoS attack
2293: Wrong facet used by num_put::do_put
2299: Effects of inaccessible key_compare::is_transparent type are not
clear
2301: Why is std::tie not constexpr?
2304: Complexity of count in unordered associative containers
2306: match_results::reference should be value_type&, not const
value_type&
2308: Clarify container destructor requirements w.r.t. std::array
2313: tuple_size should always derive from integral_constant<size_t, N>
2314: apply() should return decltype(auto) and use decay_t before
tuple_size
2315: weak_ptr should be movable
2316: weak_ptr::lock() should be atomic
2317: The type property queries should be UnaryTypeTraits returning
size_t
2320: select_on_container_copy_construction() takes allocators, not
containers
2322: Associative(initializer_list, stuff) constructors are
underspecified
2323: vector::resize(n, t)'s specification should be simplified
2324: Insert iterator constructors should use addressof()
2329: regex_match()/regex_search() with match_results should forbid
temporary strings
2330: regex("meow", regex::icase) is technically forbidden but should
be permitted
2332: regex_iterator/regex_token_iterator should forbid temporary
regexes
2339: Wording issue in nth_element
2341: Inconsistency between basic_ostream::seekp(pos) and
basic_ostream::seekp(off, dir)
2344: quoted()'s interaction with padding is unclear
2346: integral_constant's member functions should be marked noexcept
2350: min, max, and minmax should be constexpr
2356: Stability of erasure in unordered associative containers
2357: Remaining "Assignable" requirement
2359: How does regex_constants::nosubs affect basic_regex::mark_count()?
2360: reverse_iterator::operator*() is unimplementable
[1] http://libcxx.llvm.org/cxx1y_status.html
[2] http://libcxx.llvm.org/cxx1z_status.html
[3] http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html
Exp-run: antoine
MFC after: 1 month
this has many visibility problems fixed, which should help with
compiling certain ports that exercise C++11 mode (i.e. Firefox).
Also, belatedly add the LICENSE.TXT and accompanying CREDITS.TXT files,
which are referred to in all the source files.
MFC after: 1 month
MK_LIBCPLUSPLUS=yes to enable). This is a work-in-progress. It works for
me, but is not guaranteed to work for anyone else and may eat your dog.
To build C++ using libc++, add -stdlib=libc++ to your CXX and LD flags.
Bug reports welcome, bug fixes even more welcome...
Approved by: dim (mentor)
