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diff --git a/contrib/llvm-project/clang/lib/Driver/ToolChains/LazyDetector.h b/contrib/llvm-project/clang/lib/Driver/ToolChains/LazyDetector.h
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+++ b/contrib/llvm-project/clang/lib/Driver/ToolChains/LazyDetector.h
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+//===--- LazyDetector.h - Lazy ToolChain Detection --------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_LAZYDETECTOR_H
+#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_LAZYDETECTOR_H
+
+#include "clang/Driver/Tool.h"
+#include "clang/Driver/ToolChain.h"
+#include <optional>
+
+namespace clang {
+
+/// Simple wrapper for toolchain detector with costly initialization. This
+/// delays the creation of the actual detector until its first usage.
+
+template <class T> class LazyDetector {
+  const driver::Driver &D;
+  llvm::Triple Triple;
+  const llvm::opt::ArgList &Args;
+
+  std::optional<T> Detector;
+
+public:
+  LazyDetector(const driver::Driver &D, const llvm::Triple &Triple,
+               const llvm::opt::ArgList &Args)
+      : D(D), Triple(Triple), Args(Args) {}
+  T *operator->() {
+    if (!Detector)
+      Detector.emplace(D, Triple, Args);
+    return &*Detector;
+  }
+  const T *operator->() const {
+    return const_cast<T const *>(
+        const_cast<LazyDetector &>(*this).operator->());
+  }
+};
+
+} // end namespace clang
+
+#endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_LAZYDETECTOR_H