-Wconsumed is ignored on destructors

[apache-hb]

In this example the destructor is marked [[clang::callable_when(consumed)]], and the constructor is marked with [[clang::return_typestate(unconsumed)]]. Despite this there is no warning issued when the destructor is reached on an unconsumed instance of IplTag

[apache-hb]

The warning is correctly produced when the destructor of IplTag is not trivial godbolt

[llvmbot]

@llvm/issue-subscribers-c-1

Author: Elliot (apache-hb)

In [this example](https://godbolt.org/z/o54sjPjGs) the destructor is marked `[[clang::callable_when(consumed)]]`, and the constructor is marked with `[[clang::return_typestate(unconsumed)]]`. Despite this there is no warning issued when the destructor is reached on an unconsumed instance of `IplTag`

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Elliot (apache-hb)

In [this example](https://godbolt.org/z/o54sjPjGs) the destructor is marked `[[clang::callable_when(consumed)]]`, and the constructor is marked with `[[clang::return_typestate(unconsumed)]]`. Despite this there is no warning issued when the destructor is reached on an unconsumed instance of `IplTag`

[AaronBallman]

I looked into this briefly and I think the issue is that the CFG does not model a defaulted destructor correctly. I think CFGBuilder::hasTrivialDestructor() needs to be updated so that !CD->hasDefinition() || CD->hasTrivialDestructor() also looks to see if the destructor has attributes written on it, because some attributes may mean "yes this is trivial but it still has control flow effects". But I'm not 100% sure. CC @gribozavr @ymand @sgatev for additional opinions.