This reverts commit 54db16221c92eb52efbea90ad5b5d2a1d00cda3e.
Check for existence of __SIZOEF_INT128__ so we don't run those
tests on targets that don't have int128.
Unlike brace initialization, the parenthesized aggregate initialization
in C++20 does not extend the lifetime of a temporary object bound to a
reference in an aggreate. This can lead to dangling references:
```
struct A { const int& r; };
A a1(1); // well-formed, but results in a dangling reference.
```
With this patch, clang will diagnose this common dangling issues.
Fixes#101957
In C++20, a defaulted but implicitly deleted destructor is constexpr if
and only if the class has no virtual base class. This hasn't been
changed in C++23 by P2448R2.
Constexpr-ness on a deleted destructor affects almost nothing. The
`__is_literal` intrinsic is related, while the corresponding
`std::is_literal_type(_v)` utility has been removed in C++20. A recently
added example in `test/AST/ByteCode/cxx23.cpp` will become valid, and
the example is already accepted by GCC.
Clang currently behaves correctly in C++23 mode, because the
constexpr-ness on defaulted destructor is relaxed by P2448R2. But we
should make similar relaxation for an implicitly deleted destructor.
Fixes#85550.
The attached test case from
https://github.com/llvm/llvm-project/issues/117294 used to cause an
assertion because we called classifPrim() on an array type.
The new result doesn't crash but isn't exactly perfect either. Since the
problem arises when evaluating an ImplicitValueInitExpr, we have no
proper source location to point to. Point to the caller instead.
This is a subset of #68288, with hopefully narrower scope. It does not
support bitcasting to non-integral types yet.
Bitfields are supported, but only if they result in a full byte-sized
final buffer. It does not support casting from null-pointers yet or
casting from indeterminate bits.
The tests are from #68288 and partially from #74775.
The `BitcastBuffer` struct is currently always working in single bits,
but I plan to (try to) optimize this for the common full-byte case.
... tried their initializer already. In that case, diagnose the
non-const initializer instead of the reference to a non-constexpr
variable later. This is used in a lot of openmp tests.
According to [P0533R9](https://wg21.link/P0533R9), the C++ standard
library functions corresponding to the C macros in `[c.math.abs]` are
now `constexpr`.
To implement this feature in libc++, we must make the built-in abs
function `constexpr`. This patch adds the implementation of a
`constexpr` abs function for the current constant evaluator and the new
bytecode interpreter.
It is important to note that in 2's complement systems, the absolute
value of the most negative value is out of range. In gcc, it will result
in an out-of-range error and will not be evaluated as constants. We
follow the same approach here.
The global scope we create when evaluating expressions might free some
of the dynamic memory allocations, so we can't check for memory leaks
before destroying it.
