llvm/llvm/include/llvm/Support/MSVCErrorWorkarounds.h

//===--- MSVCErrorWorkarounds.h - Enable future<Error> in MSVC --*- 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
//
//===----------------------------------------------------------------------===//
//
// MSVC's promise/future implementation requires types to be default
// constructible, so this header provides analogues of Error an Expected
// that are default constructed in a safely destructible state.
//
// FIXME: Kill off this header and migrate all users to Error/Expected once we
//        move to MSVC versions that support non-default-constructible types.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_MSVCERRORWORKAROUNDS_H
#define LLVM_SUPPORT_MSVCERRORWORKAROUNDS_H

#include "llvm/Support/Error.h"

namespace llvm {

// A default-constructible llvm::Error that is suitable for use with MSVC's
// std::future implementation which requires default constructible types.
class MSVCPError : public Error { … };

// A default-constructible llvm::Expected that is suitable for use with MSVC's
// std::future implementation, which requires default constructible types.
template <typename T> class MSVCPExpected : public Expected<T> { … };

} // end namespace llvm

#endif // LLVM_SUPPORT_MSVCERRORWORKAROUNDS_H