[clang] [clang] Diagnose dangling issues for the "Container<GSLPointer>" case. (PR #107213)

[Haojian Wu via cfe-commits]

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@@ -6690,6 +6690,20 @@ When the Owner's lifetime ends, it will consider the Pointer to be dangling.
     P.getInt(); // P is dangling
   }
 
+If a template class is annotated with [[gsl::Owner]], and the first instantiated
+template argument is a [[gsl::Pointer]] type, the analysis will consider the
+instantiated class as a container of the pointer. When constructing such an
+object from a GSL owner object, the analysis will assume that the container
+holds a pointer to the owner object. Consequently, when the owner object is
+destroyed, the pointer will be considered dangling.
+
+.. code-block:: c++
+
+   int f() {
+     std::vector<std::string_view> v = {std::string();}; // v holds a dangling pointer.
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hokein wrote:

Done.

https://github.com/llvm/llvm-project/pull/107213