[clang] [Clang] Add __builtin_get_counted_by builtin (PR #102549)

[via cfe-commits]

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@@ -6590,8 +6590,34 @@ ExprResult Sema::BuildCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
     return CallExpr::Create(Context, Fn, ArgExprs, Context.DependentTy,
                             VK_PRValue, RParenLoc, CurFPFeatureOverrides());
   }
-  return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs, RParenLoc,
-                               ExecConfig, IsExecConfig);
+
+  Result = BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs, RParenLoc,
+                                 ExecConfig, IsExecConfig);
+
+  if (FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl);
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Sirraide wrote:

This definitely does not seem like the right place to do any of this... So yeah, this should definitely get custom type checking (because it effectively already does; it’s just done here instead of where all the other builtins are handled).

https://github.com/llvm/llvm-project/pull/102549