This patch makes the bind placeholders in std::placeholders both (1) const and
(2) constexpr (See below).
This is technically a breaking change for any code using the placeholders
outside of std::bind and depending on them being non-const. However I don't
think this will break any real world code.
(1) Previously the placeholders were non-const extern globals in all
dialects. This patch changes these extern globals to be const in all dialects.
Since the cv-qualifiers don't participate in name mangling for globals this
is an ABI compatible change.
(2) Make the placeholders constexpr in C++11 and beyond. Although LWG 2488 only
applies to C++17 I don't see any reason not to backport this change.
llvm-svn: 273824
The primary purpose of this patch is to add the 'is_callable' traits.
Since 'is_nothrow_callable' required making 'INVOKE' conditionally noexcept
I also took this oppertunity to implement a constexpr version of INVOKE.
This fixes 'std::experimental::apply' which required constexpr 'INVOKE support'.
This patch will be followed up with some cleanup. Primarly removing most
of "__member_function_traits" since it's no longer used by INVOKE (in C++11 at least).
llvm-svn: 266836
<__functional_03> provides the C++03 definitions for std::memfun and
std::function. However the interaction between <functional> and <__functional_03>
is ugly and duplicates code needlessly. This patch cleans up how the two
headers work together.
The major changes are:
- Provide placeholders, is_bind_expression and is_placeholder in <functional>
for both C++03 and C++11.
- Provide bad_function_call, function fwd decl,
__maybe_derive_from_unary_function and __maybe_derive_from_binary_function
in <functional> for both C++03 and C++11.
- Move the <__functional_03> include to the bottom of <functional>. This makes
it easier to see how <__functional_03> interacts with <functional>
- Remove a commented out implementation of bind in C++03. It's never going
to get implemented.
- Mark almost all std::bind tests as unsupported in C++03. std::is_placeholder
works in C++03 and C++11. std::is_bind_expression is provided in C++03 but
always returns false.
llvm-svn: 242870
The SFINAE on the function __mu(Fn, Args...) that evaluates nested bind
expressions always tries to deduce the return type for Fn(Args...) even when Fn
is not a nested bind expression. This can cause hard compile errors when the
instantation of Fn(Args...) is ill-formed. This patch prevents the instantation
of __invoke_of<Fn, Args...> unless Fn is actually a bind expression.
Bug reportand patch from Michel Morin.
http://llvm.org/bugs/show_bug.cgi?id=22003
llvm-svn: 224753
Eric Fiselier