Summary:
The standard requires tuple have the following constructors:
```
tuple(tuple<OtherTypes...> const&);
tuple(tuple<OtherTypes...> &&);
tuple(pair<T1, T2> const&);
tuple(pair<T1, T2> &&);
tuple(array<T, N> const&);
tuple(array<T, N> &&);
```
However libc++ implements these as a single constructor with the signature:
```
template <class TupleLike, enable_if_t<__is_tuple_like<TupleLike>::value>>
tuple(TupleLike&&);
```
This causes the constructor to reject types derived from tuple-like types; Unlike if we had all of the concrete overloads, because they cause the derived->base conversion in the signature.
This patch fixes this issue by detecting derived types and the tuple-like base they are derived from. It does this by creating an overloaded function with signatures for each of tuple/pair/array and checking if the possibly derived type can convert to any of them.
This patch fixes [PR17550]( https://llvm.org/bugs/show_bug.cgi?id=17550)
This patch
Reviewers: mclow.lists, K-ballo, mpark, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D27606
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@289727 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of storing double in double and then truncating to int, store int in long
and then widen to long long. This preserves test coverage (as these tests are
interested in various tuple conversions) while avoiding truncation warnings.
test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_pair.pass.cpp
Since we aren't physically truncating anymore, t1 is equal to p0.
test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_copy.pass.cpp
One edit is different from the usual pattern. Previously, we were storing
double in double and then converting to A, which has an implicitly converting
constructor from int. Now, we're storing int in int and then converting to A,
avoiding the truncation.
Fixes D27542.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@289109 91177308-0d34-0410-b5e6-96231b3b80d8
I think I've solved issues with is_assignable and references to incomplete
types. The updated patch adds tests for this case.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@276603 91177308-0d34-0410-b5e6-96231b3b80d8
This is a breaking change. The SFINAE required is instantiated the second
the class is instantiated, and this can cause hard SFINAE errors
when applied to references to incomplete types. Ex.
struct IncompleteType;
extern IncompleteType it;
std::tuple<IncompleteType&> t(it); // SFINAE will blow up.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@276598 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: No declaration for the type `tuple` is given in c++03 or c++98 modes. Mark all tests that use the actual `tuple` type as UNSUPPORTED.
Reviewers: jroelofs, mclow.lists, danalbert
Reviewed By: danalbert
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D5956
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@229808 91177308-0d34-0410-b5e6-96231b3b80d8
