We can't access the calling frame in that case.

Fixes https://github.com/llvm/llvm-project/issues/169032

We need to get the element type size at bytecode generation time to
check. We also need to diagnose this in the LHS == RHS case.

... for dynamic memory allocation. This happens when the requested array
size is too large.

Fixes #152951

This patch fixes a crash in the constexpr interpreter when evaluating
`new T[n]` with a negative element count.

Fixes https://github.com/llvm/llvm-project/issues/152904

This fixes an old todo item about wrong allocation counting and some
diagnostic differences.

This fixes a mismatch in diagnostic output with the current intepreter.

In the attached test case, one pointer points to the `Derived` class and
one to `Base`, but they should compare equal. They didn't because those
two bases are saved at different offsets in the block. Use
`computeOffsetForComparison` not just for unions and fix it to work in
the more general cases.

Discard all the parameters we don't care about.

placement-new'ing an object with a dead base object is not allowed, so
we need to check all the pointer bases.