[Clang] Address post commit feedbacks in #89906 (#90495)

* Fix a leak
* Fix a maybe unused warning
* Fix incorrect cxx_status entry

Author: cor3ntin

clang/include/clang/Sema/DeclSpec.h

@@ -1811,15 +1811,15 @@ class DecompositionDeclarator {
       : Bindings(nullptr), NumBindings(0), DeleteBindings(false) {}
   DecompositionDeclarator(const DecompositionDeclarator &G) = delete;
   DecompositionDeclarator &operator=(const DecompositionDeclarator &G) = delete;
-  ~DecompositionDeclarator() {
-    if (DeleteBindings)
-      delete[] Bindings;
-  }
+  ~DecompositionDeclarator() { clear(); }
 
   void clear() {
     LSquareLoc = RSquareLoc = SourceLocation();
     if (DeleteBindings)
       delete[] Bindings;
+    else
+      llvm::for_each(llvm::MutableArrayRef(Bindings, NumBindings),
+                     [](Binding &B) { B.Attrs.reset(); });
     Bindings = nullptr;
     NumBindings = 0;
     DeleteBindings = false;

clang/lib/AST/DeclBase.cpp

@@ -1115,7 +1115,7 @@ int64_t Decl::getID() const {
 
 const FunctionType *Decl::getFunctionType(bool BlocksToo) const {
   QualType Ty;
-  if (const auto *D = dyn_cast<BindingDecl>(this))
+  if (isa<BindingDecl>(this))
     return nullptr;
   else if (const auto *D = dyn_cast<ValueDecl>(this))
     Ty = D->getType();

clang/www/cxx_status.html

@@ -177,7 +177,7 @@ <h2 id="cxx26">C++2c implementation status</h2>
  <tr>
   <td>Attributes for Structured Bindings</td>
   <td><a href="https://wg21.link/P0609R3">P0609R3</a></td>
-  <td class="none" align="center">No</td>
+  <td class="none" align="center">Clang 19</td>
  </tr>
  <tr>
   <td>Module Declarations Shouldn’t be Macros</td>
@@ -187,7 +187,7 @@ <h2 id="cxx26">C++2c implementation status</h2>
  <tr>
   <td>Trivial infinite loops are not Undefined Behavior</td>
   <td><a href="https://wg21.link/P2809R3">P2809R3</a> (<a href="#dr">DR</a>)</td>
-  <td class="unreleased" align="center">Clang 19</td>
+  <td class="unreleased" align="center">No</td>
  </tr>
  <tr>
   <td>Erroneous behaviour for uninitialized reads</td>