llvm/clang/include/clang/Basic/LangOptions.def

//===--- LangOptions.def - Language option database -------------*- 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
//
//===----------------------------------------------------------------------===//
//
// This file defines the language options. Users of this file must
// define the LANGOPT macro to make use of this information. The arguments to
// the macro are:
//   LANGOPT(Name, Bits, DefaultValue, Description)
// Note that the DefaultValue must be a constant value (literal or enumeration);
// it cannot depend on the value of another language option.
//
// Optionally, the user may also define:
//
// BENIGN_LANGOPT: for options that don't affect the construction of the AST in
//     any way (that is, the value can be different between an implicit module
//     and the user of that module).
//
// COMPATIBLE_LANGOPT: for options that affect the construction of the AST in
//     a way that doesn't prevent interoperability (that is, the value can be
//     different between an explicit module and the user of that module).
//
// ENUM_LANGOPT: for options that have enumeration, rather than unsigned, type.
//
// VALUE_LANGOPT: for options that describe a value rather than a flag.
//
// BENIGN_ENUM_LANGOPT, COMPATIBLE_ENUM_LANGOPT,
// BENIGN_VALUE_LANGOPT, COMPATIBLE_VALUE_LANGOPT: combinations of the above.
//
// FIXME: Clients should be able to more easily select whether they want
// different levels of compatibility versus how to handle different kinds
// of option.
//
// The Description field should be a noun phrase, for instance "frobbing all
// widgets" or "C's implicit blintz feature".
//===----------------------------------------------------------------------===//

#ifndef LANGOPT
#  error Define the LANGOPT macro to handle language options
#endif

#ifndef COMPATIBLE_LANGOPT
#  define COMPATIBLE_LANGOPT(Name, Bits, Default, Description) \
     LANGOPT(Name, Bits, Default, Description)
#endif

#ifndef BENIGN_LANGOPT
#  define BENIGN_LANGOPT(Name, Bits, Default, Description) \
     COMPATIBLE_LANGOPT(Name, Bits, Default, Description)
#endif

#ifndef ENUM_LANGOPT
#  define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
     LANGOPT(Name, Bits, Default, Description)
#endif

#ifndef COMPATIBLE_ENUM_LANGOPT
#  define COMPATIBLE_ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
     ENUM_LANGOPT(Name, Type, Bits, Default, Description)
#endif

#ifndef BENIGN_ENUM_LANGOPT
#  define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
     COMPATIBLE_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
#endif

#ifndef VALUE_LANGOPT
#  define VALUE_LANGOPT(Name, Bits, Default, Description) \
     LANGOPT(Name, Bits, Default, Description)
#endif

#ifndef COMPATIBLE_VALUE_LANGOPT
#  define COMPATIBLE_VALUE_LANGOPT(Name, Bits, Default, Description) \
     VALUE_LANGOPT(Name, Bits, Default, Description)
#endif

#ifndef BENIGN_VALUE_LANGOPT
#  define BENIGN_VALUE_LANGOPT(Name, Bits, Default, Description) \
     COMPATIBLE_VALUE_LANGOPT(Name, Bits, Default, Description)
#endif

// FIXME: A lot of the BENIGN_ options should be COMPATIBLE_ instead.
LANGOPT( … }