RedDocMD marked an inline comment as done.
RedDocMD added inline comments.
================
Comment at: clang/test/Analysis/smart-ptr-text-output.cpp:339
+void makeUniqueForOverwriteReturnsNullUniquePtr() {
+ auto P = std::make_unique_for_overwrite<A>(); // expected-note
{{std::unique_ptr 'P' constructed by std::make_unique_for_overwrite is null}}
+ *P; // expected-warning
{{Dereference of null smart pointer 'P' [alpha.cplusplus.SmartPtr]}}
----------------
NoQ wrote:
> Mmm wait a sec, that doesn't look like what the spec says.
>
> https://en.cppreference.com/w/cpp/memory/unique_ptr/make_unique:
> > Same as (1), except that the object is default-initialized. This overload
> > participates in overload resolution only if T is not an array type. The
> > function is equivalent to `unique_ptr<T>(new T)`
>
> It zero-initializes the //pointee//, not the //pointer//.
>
> The difference between `std::make_unique<A>()` and
> `std::make_unique_for_overwrite<A>()` is the difference between
> value-initialization (invoking the default constructor) and
> zero-initialization (simply filling the buffer with `0`s).
Oops! Look like I completely misunderstood the spec.
So basically, the inner pointer is //not// null, and we have the same
assumptions that apply for `std::make_unique`. Only problem is that, for
primitive types, the value obtained on de-referencing is undefined.
Repository:
rG LLVM Github Monorepo
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D103750/new/
https://reviews.llvm.org/D103750
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
