25 lines
623 B
C++
25 lines
623 B
C++
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//===----------------------------------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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// <optional>
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// A program that necessitates the instantiation of template optional for a
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// reference type is ill-formed.
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#include <optional>
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int main()
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{
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#if _LIBCPP_STD_VER > 11
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std::optional<const int&> opt;
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#else
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#error
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#endif // _LIBCPP_STD_VER > 11
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}
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