The key changes in this patch are:
1. Remove the zero-argument overload in mem_fn. A member function must always
be invoked with at least one argument, the class instance. The zero-argument
operator()() in mem_fn would cause mem_fn to fail to compile when because
the call to '__invoke(pm)' is not well formed.
2. Prevent evaluation of '__apply_cv<Tp, Ret>' when 'Ret' is a function type.
'Ret' is a function type whenever 'Ret Tp::*' is a pointer to member function.
Attempting to add cv and ref qualifiers to a function type can cause a hard
compile error.
3. Remove the dummy overload __invoke(Rp Tp::*). It was present to help work
around #1. It will be replaced with a different '__invoke' overload that
represents a bad call to invoke.
After applying this patch the test func.wrap.func.inv/invoke.pass.cpp now
passes.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@243370 91177308-0d34-0410-b5e6-96231b3b80d8
This patch does a couple of things to get __invoke working for free-functions
and call objects.
1. Turn all uses of declval<Tp>() into declval<Tp&>(). The C++03 __invoke only
supports lvalues but it will be used when the compiler supports rvalue
references but not variadic templates. This change makes sure we don't
generate an rvalue.
2. Call objects for bullet 5 are now passed by reference and not value. Copying
the functor is incorrect. It will fail to compile for non-copyable functors
and it will discard cv-qualifiers on the call object, possibly leading to the
wrong function being called. I suspect that the reason the call object
was originally taken by value was to support temporary call objects.
However __invoke is only used internally and it is never given a temporary.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@243368 91177308-0d34-0410-b5e6-96231b3b80d8
This patch removes a large amount of duplicate code found in both
<__functional_base> and <__functional_base_03>. The only code that remains
in <__functional_base_03> is the C++03 implementation of __invoke and
__invoke_return.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@242951 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The bug can be found here: http://llvm.org/bugs/show_bug.cgi?id=22468
`__invoke_void_return_wrapper` is needed to properly handle calling a function that returns a value but where the std::function return type is void. Without this '-Wsystem-headers' will cause `function::operator()(...)` to not compile.
Reviewers: eugenis, K-ballo, mclow.lists
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D7444
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@228705 91177308-0d34-0410-b5e6-96231b3b80d8
