This check implements the typebased semantic of `gsl::owner`.
Meaning, that
- only `gsl::owner` is allowed to get `delete`d
- `new` expression must be assigned to `gsl::owner`
- function calls that expect `gsl::owner` as argument, must get either an owner
or a newly created and recognized resource (in the moment only `new`ed memory)
- assignment to `gsl::owner` must be either a resource or another owner
- functions returning an `gsl::owner` are considered as factories, and their result
must be assigned to an `gsl::owner`
- classes that have an `gsl::owner`-member must declare a non-default destructor
There are some problems that occur when typededuction is in place.
For example `auto Var = function_that_returns_owner();` the type of `Var` will not be
an `gsl::owner`. This case is catched, and explicitly noted.
But cases like fully templated functions
```
template <typename T>
void f(T t) { delete t; }
// ...
f(gsl::owner<int*>(new int(42)));
```
Will created false positive (the deletion is problematic), since the type deduction
removes the wrapping `typeAlias`.
Codereview in D36354
llvm-svn: 313067
6ccc1c342a