Eric Fiselier 70192a9efb [libcxx] Rewrite C++03 __invoke. ... Summary: This patch rewrites the C++03 `__invoke` and related meta-programming. There are a number of major changes. `__invoke` in C++03 now has a fallback overload for when the invoke expression is ill-formed (similar to C++11). This means that the `__invoke_return` traits will return `__nat` when `__invoke(...)` is ill formed. This would previously cause a compile error. Bullets 1-4 of `__invoke` have been rewritten. In the old version `__invoke` had 32 overloads for bullets 1 and 2, one for each possible cv-qualified function signature with arities 0-3. 64 overloads would be needed to support member functions with varargs. Currently these overloads were fundamentally broken. An example overload looked like: ``` template <class Rp, class Tp, class T1, class A0> Rp __invoke(Rp (Tp::*pm)(A0) const, T1&, A0&) ``` Because `A0` appeared in two different deducible contexts it would have to deduce to be an exact match or the overload would be rejected. This is made even worse because `A0` appears without a reference qualifier in the member function signature and with a reference qualifier as an `__invoke` parameter. This means that only member functions that took all of their arguments by value could be matched. One possible fix would be to make the second occurrence of `A0` appear in a non-deducible context. This way any type convertible to `A0` could be passed as the first parameter. The benefit of this approach is that the signature of the member function enforces the arity and types taken by the `__invoke` signature it generates. However nothing in the `INVOKE` specification requires this behavior. My solution is to use a `__invoke_enable_if<PM_Type, Tp>` metafunction to selectively enable the `__invoke` overloads for bullets 1, 2, 3 and 4. It uses `__member_function_traits` to inspect and extract the return type and class type of the pointer to member. Using `__member_function_traits` to inspect `PM_Type` also allows us to reduce the number of `__invoke` overloads from 32 to 8 and add varargs support at the same time. Because `__invoke_enable_if` knows the exact return type of `__invoke` for bullets 1-4 we no longer need to use `decltype(__invoke(...))` to compute the return type in the `__invoke_return*` traits. This will reduce the problems caused by `#define decltype(X) __typeof__(X)` in C++03. Tests for this change have already been committed. All tests in `test/std/utilities/function.objects` now pass in C++03, previously there were 20 failures. Reviewers: K-ballo, howard.hinnant, mclow.lists Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D11553 llvm-svn: 246068		2015-08-26 20:15:02 +00:00
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arithmetic.operations	In C++03, a bunch of the arithmetic/logical/comparison functors (such as negate/bit_not.pass/logical_not) were defined as deriving from unary_funtion. That restriction was removed in C++11, but the tests still check for this. Change the test to look for the embedded types first_argument/second_argument/result_type. No change to the library, just more standards-compliant tests. Thanks to STL @ Microsoft for the suggestion.	2015-01-07 21:51:30 +00:00
bind	Cleanup <__functional_03>	2015-07-22 04:14:38 +00:00
bitwise.operations	Get tests running with warnings. Fix warnings in headers and tests	2015-02-05 20:28:37 +00:00
comparisons	Missed one comparison test in r225375	2015-01-07 20:40:28 +00:00
func.def
func.invoke	Remove non-ascii characters	2015-07-14 20:45:48 +00:00
func.memfn
func.require	Checking more __invoke tests.	2015-07-28 01:25:36 +00:00
func.wrap	[libcxx] Fix PR23589: std::function doesn't recognize null pointer to varargs function.	2015-08-18 19:41:51 +00:00
logical.operations	In C++03, a bunch of the arithmetic/logical/comparison functors (such as negate/bit_not.pass/logical_not) were defined as deriving from unary_funtion. That restriction was removed in C++11, but the tests still check for this. Change the test to look for the embedded types first_argument/second_argument/result_type. No change to the library, just more standards-compliant tests. Thanks to STL @ Microsoft for the suggestion.	2015-01-07 21:51:30 +00:00
negators	In C++03, a bunch of the arithmetic/logical/comparison functors (such as negate/bit_not.pass/logical_not) were defined as deriving from unary_funtion. That restriction was removed in C++11, but the tests still check for this. Change the test to look for the embedded types first_argument/second_argument/result_type. No change to the library, just more standards-compliant tests. Thanks to STL @ Microsoft for the suggestion.	2015-01-07 21:51:30 +00:00
refwrap	[libcxx] Rewrite C++03 __invoke.	2015-08-26 20:15:02 +00:00
unord.hash	Cleaning up the test suite; remove some includes of non-standard file <__config>	2015-01-18 19:05:51 +00:00
version.pass.cpp