Summary:
There is no reason to guard `tuple_size`, `tuple_element` and `get<I>(...)` for pair and array inside of `<__tuple>` so that they are only available when we have variadic templates.
This requires there be redundant declarations and definitions. It also makes it easy to get things wrong.
For example the following code should compile (and does in c++11).
```
#define _LIBCPP_HAS_NO_VARIADICS
#include <array>
int main()
{
static_assert((std::tuple_size<std::array<int, 10> volatile>::value == 10), "");
}
```
This patch lifts the non-variadic parts of `tuple_size`, `tuple_types`, and `get<I>(...)` to the top of `<__tuple>` where they don't require variadic templates. This patch also removes `<__tuple_03>` because there is no longer a need for it.
Reviewers: danalbert, K-ballo, mclow.lists
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D7774
llvm-svn: 232492
Summary:
http://llvm.org/bugs/show_bug.cgi?id=18345
Tuple's constructor and assignment operators for "tuple-like" types evaluates __make_tuple_types unnecessarily. In the case of a large array this can blow the template instantiation depth.
Ex:
```
#include <array>
#include <tuple>
#include <memory>
typedef std::array<int, 1256> array_t;
typedef std::tuple<array_t> tuple_t;
int main() {
array_t a;
tuple_t t(a); // broken
t = a; // broken
// make_shared uses tuple behind the scenes. This bug breaks this code.
std::make_shared<array_t>(a);
}
```
To prevent this from happening we delay the instantiation of `__make_tuple_types` until after we perform the length check. Currently `__make_tuple_types` is instantiated at the same time that the length check .
Test Plan: Two tests have been added. One for the "tuple-like" constructors and another for the "tuple-like" assignment operator.
Reviewers: mclow.lists, EricWF
Reviewed By: EricWF
Subscribers: K-ballo, cfe-commits
Differential Revision: http://reviews.llvm.org/D4467
llvm-svn: 220769