[clang] [clang] Implement -Walloc-size diagnostic option (PR #150028)

[Erich Keane via cfe-commits]

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@@ -3256,6 +3257,14 @@ class CallExpr : public Expr {
     setDependence(getDependence() | ExprDependence::TypeValueInstantiation);
   }
 
+  /// Try to get the alloc_size attribute of the callee. May return null.
+  const AllocSizeAttr *getAllocSizeAttr() const;
+
+  /// Get the total size in bytes allocated by calling a function decorated with
+  /// alloc_size. Returns true if the the result was successfully evaluated.
+  bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
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erichkeane wrote:

I'd rather this return an optional.

https://github.com/llvm/llvm-project/pull/150028