[clang] [Clang] Introduce malloc_span attribute (PR #167010)

[Marco Elver via cfe-commits]

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@@ -5247,6 +5247,21 @@ yet implemented in clang.
   }];
 }
 
+def MallocSpanDocs : Documentation {
+  let Category = DocCatFunction;
+  let Heading = "malloc_span";
+  let Content = [{
+The ``malloc_span`` attribute can be used to mark that a function which acts
+like a system memory allocation function and returns a span-like structure
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melver wrote:

```suggestion
like a system memory allocation function and returns a span-like structure,
```

https://github.com/llvm/llvm-project/pull/167010