meson/mesonbuild/compilers/cpp.py

# SPDX-License-Identifier: Apache-2.0
# Copyright 2012-2017 The Meson development team

from __future__ import annotations

import copy
import functools
import os.path
import typing as T

from .. import coredata
from .. import mlog
from ..mesonlib import MesonException, version_compare, OptionKey

from .compilers import (
    gnu_winlibs,
    msvc_winlibs,
    Compiler,
    CompileCheckMode,
)
from .c_function_attributes import CXX_FUNC_ATTRIBUTES, C_FUNC_ATTRIBUTES
from .mixins.clike import CLikeCompiler
from .mixins.ccrx import CcrxCompiler
from .mixins.ti import TICompiler
from .mixins.arm import ArmCompiler, ArmclangCompiler
from .mixins.visualstudio import MSVCCompiler, ClangClCompiler
from .mixins.gnu import GnuCompiler, gnu_common_warning_args, gnu_cpp_warning_args
from .mixins.intel import IntelGnuLikeCompiler, IntelVisualStudioLikeCompiler
from .mixins.clang import ClangCompiler
from .mixins.elbrus import ElbrusCompiler
from .mixins.pgi import PGICompiler
from .mixins.emscripten import EmscriptenMixin
from .mixins.metrowerks import MetrowerksCompiler
from .mixins.metrowerks import mwccarm_instruction_set_args, mwcceppc_instruction_set_args

if T.TYPE_CHECKING:
    from ..coredata import MutableKeyedOptionDictType, KeyedOptionDictType
    from ..dependencies import Dependency
    from ..envconfig import MachineInfo
    from ..environment import Environment
    from ..linkers.linkers import DynamicLinker
    from ..mesonlib import MachineChoice
    from ..programs import ExternalProgram
    CompilerMixinBase = CLikeCompiler
else:
    CompilerMixinBase = object

_ALL_STDS = ['c++98', 'c++0x', 'c++03', 'c++1y', 'c++1z', 'c++11', 'c++14', 'c++17', 'c++2a', 'c++20', 'c++23', 'c++26']
_ALL_STDS += [f'gnu{std[1:]}' for std in _ALL_STDS]
_ALL_STDS += ['vc++11', 'vc++14', 'vc++17', 'vc++20', 'vc++latest', 'c++latest']


def non_msvc_eh_options(eh: str, args: T.List[str]) -> None:
    if eh == 'none':
        args.append('-fno-exceptions')
    elif eh in {'s', 'c'}:
        mlog.warning(f'non-MSVC compilers do not support {eh} exception handling. '
                     'You may want to set eh to \'default\'.', fatal=False)

class CPPCompiler(CLikeCompiler, Compiler):
    def attribute_check_func(self, name: str) -> str:
        try:
            return CXX_FUNC_ATTRIBUTES.get(name, C_FUNC_ATTRIBUTES[name])
        except KeyError:
            raise MesonException(f'Unknown function attribute "{name}"')

    language = 'cpp'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        # If a child ObjCPP class has already set it, don't set it ourselves
        Compiler.__init__(self, ccache, exelist, version, for_machine, info,
                          is_cross=is_cross, linker=linker,
                          full_version=full_version)
        CLikeCompiler.__init__(self, exe_wrapper)

    @classmethod
    def get_display_language(cls) -> str:
        return 'C++'

    def get_no_stdinc_args(self) -> T.List[str]:
        return ['-nostdinc++']

    def get_no_stdlib_link_args(self) -> T.List[str]:
        return ['-nostdlib++']

    def sanity_check(self, work_dir: str, environment: 'Environment') -> None:
        code = 'class breakCCompiler;int main(void) { return 0; }\n'
        return self._sanity_check_impl(work_dir, environment, 'sanitycheckcpp.cc', code)

    def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
        # -fpermissive allows non-conforming code to compile which is necessary
        # for many C++ checks. Particularly, the has_header_symbol check is
        # too strict without this and always fails.
        return super().get_compiler_check_args(mode) + ['-fpermissive']

    def has_header_symbol(self, hname: str, symbol: str, prefix: str,
                          env: 'Environment', *,
                          extra_args: T.Union[None, T.List[str], T.Callable[[CompileCheckMode], T.List[str]]] = None,
                          dependencies: T.Optional[T.List['Dependency']] = None) -> T.Tuple[bool, bool]:
        # Check if it's a C-like symbol
        found, cached = super().has_header_symbol(hname, symbol, prefix, env,
                                                  extra_args=extra_args,
                                                  dependencies=dependencies)
        if found:
            return True, cached
        # Check if it's a class or a template
        if extra_args is None:
            extra_args = []
        t = f'''{prefix}
        #include <{hname}>
        using {symbol};
        int main(void) {{ return 0; }}'''
        return self.compiles(t, env, extra_args=extra_args,
                             dependencies=dependencies)

    def _test_cpp_std_arg(self, cpp_std_value: str) -> bool:
        # Test whether the compiler understands a -std=XY argument
        assert cpp_std_value.startswith('-std=')

        # This test does not use has_multi_arguments() for two reasons:
        # 1. has_multi_arguments() requires an env argument, which the compiler
        #    object does not have at this point.
        # 2. even if it did have an env object, that might contain another more
        #    recent -std= argument, which might lead to a cascaded failure.
        CPP_TEST = 'int i = static_cast<int>(0);'
        with self.compile(CPP_TEST, extra_args=[cpp_std_value], mode=CompileCheckMode.COMPILE) as p:
            if p.returncode == 0:
                mlog.debug(f'Compiler accepts {cpp_std_value}:', 'YES')
                return True
            else:
                mlog.debug(f'Compiler accepts {cpp_std_value}:', 'NO')
                return False

    @functools.lru_cache()
    def _find_best_cpp_std(self, cpp_std: str) -> str:
        # The initial version mapping approach to make falling back
        # from '-std=c++14' to '-std=c++1y' was too brittle. For instance,
        # Apple's Clang uses a different versioning scheme to upstream LLVM,
        # making the whole detection logic awfully brittle. Instead, let's
        # just see if feeding GCC or Clang our '-std=' setting works, and
        # if not, try the fallback argument.
        CPP_FALLBACKS = {
            'c++11': 'c++0x',
            'gnu++11': 'gnu++0x',
            'c++14': 'c++1y',
            'gnu++14': 'gnu++1y',
            'c++17': 'c++1z',
            'gnu++17': 'gnu++1z',
            'c++20': 'c++2a',
            'gnu++20': 'gnu++2a',
            'c++23': 'c++2b',
            'gnu++23': 'gnu++2b',
            'c++26': 'c++2c',
            'gnu++26': 'gnu++2c',
        }

        # Currently, remapping is only supported for Clang, Elbrus and GCC
        assert self.id in frozenset(['clang', 'lcc', 'gcc', 'emscripten', 'armltdclang', 'intel-llvm'])

        if cpp_std not in CPP_FALLBACKS:
            # 'c++03' and 'c++98' don't have fallback types
            return '-std=' + cpp_std

        for i in (cpp_std, CPP_FALLBACKS[cpp_std]):
            cpp_std_value = '-std=' + i
            if self._test_cpp_std_arg(cpp_std_value):
                return cpp_std_value

        raise MesonException(f'C++ Compiler does not support -std={cpp_std}')

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = super().get_options()
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts.update({
            key: coredata.UserStdOption('C++', _ALL_STDS),
        })
        return opts


class _StdCPPLibMixin(CompilerMixinBase):

    """Detect whether to use libc++ or libstdc++."""

    @functools.lru_cache(None)
    def language_stdlib_only_link_flags(self, env: Environment) -> T.List[str]:
        """Detect the C++ stdlib and default search dirs

        As an optimization, this method will cache the value, to avoid building the same values over and over

        :param env: An Environment object
        :raises MesonException: If a stdlib cannot be determined
        """

        # We need to apply the search prefix here, as these link arguments may
        # be passed to a different compiler with a different set of default
        # search paths, such as when using Clang for C/C++ and gfortran for
        # fortran.
        search_dirs = [f'-L{d}' for d in self.get_compiler_dirs(env, 'libraries')]

        machine = env.machines[self.for_machine]
        assert machine is not None, 'for mypy'

        # We need to determine whether to use libc++ or libstdc++. We can't
        # really know the answer in most cases, only the most likely answer,
        # because a user can install things themselves or build custom images.
        search_order: T.List[str] = []
        if machine.system in {'android', 'darwin', 'dragonfly', 'freebsd', 'netbsd', 'openbsd'}:
            search_order = ['c++', 'stdc++']
        else:
            search_order = ['stdc++', 'c++']
        for lib in search_order:
            if self.find_library(lib, env, []) is not None:
                return search_dirs + [f'-l{lib}']
        # TODO: maybe a bug exception?
        raise MesonException('Could not detect either libc++ or libstdc++ as your C++ stdlib implementation.')


class ClangCPPCompiler(_StdCPPLibMixin, ClangCompiler, CPPCompiler):

    _CPP23_VERSION = '>=12.0.0'
    _CPP26_VERSION = '>=17.0.0'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 defines: T.Optional[T.Dict[str, str]] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        ClangCompiler.__init__(self, defines)
        default_warn_args = ['-Wall', '-Winvalid-pch']
        self.warn_args = {'0': [],
                          '1': default_warn_args,
                          '2': default_warn_args + ['-Wextra'],
                          '3': default_warn_args + ['-Wextra', '-Wpedantic'],
                          'everything': ['-Weverything']}

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        key = OptionKey('key', machine=self.for_machine, lang=self.language)
        opts.update({
            key.evolve('debugstl'): coredata.UserBooleanOption(
                'STL debug mode',
                False,
            ),
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
            key.evolve('rtti'): coredata.UserBooleanOption('Enable RTTI', True),
        })
        cppstd_choices = [
            'c++98', 'c++03', 'c++11', 'c++14', 'c++17', 'c++1z', 'c++2a', 'c++20',
        ]
        if version_compare(self.version, self._CPP23_VERSION):
            cppstd_choices.append('c++23')
        if version_compare(self.version, self._CPP26_VERSION):
            cppstd_choices.append('c++26')
        std_opt = opts[key.evolve('std')]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(cppstd_choices, gnu=True)
        if self.info.is_windows() or self.info.is_cygwin():
            opts.update({
                key.evolve('winlibs'): coredata.UserArrayOption(
                    'Standard Win libraries to link against',
                    gnu_winlibs,
                ),
            })
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append(self._find_best_cpp_std(std.value))

        non_msvc_eh_options(options[key.evolve('eh')].value, args)

        if options[key.evolve('debugstl')].value:
            args.append('-D_GLIBCXX_DEBUG=1')

            # We can't do _LIBCPP_DEBUG because it's unreliable unless libc++ was built with it too:
            # https://discourse.llvm.org/t/building-a-program-with-d-libcpp-debug-1-against-a-libc-that-is-not-itself-built-with-that-define/59176/3
            # Note that unlike _GLIBCXX_DEBUG, _MODE_DEBUG doesn't break ABI. It's just slow.
            if version_compare(self.version, '>=18'):
                args.append('-D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_DEBUG')

        if not options[key.evolve('rtti')].value:
            args.append('-fno-rtti')

        return args

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        if self.info.is_windows() or self.info.is_cygwin():
            # without a typedict mypy can't understand this.
            key = OptionKey('winlibs', machine=self.for_machine, lang=self.language)
            libs = options[key].value.copy()
            assert isinstance(libs, list)
            for l in libs:
                assert isinstance(l, str)
            return libs
        return []

    def get_assert_args(self, disable: bool) -> T.List[str]:
        args: T.List[str] = []
        if disable:
            return ['-DNDEBUG']

        # Clang supports both libstdc++ and libc++
        args.append('-D_GLIBCXX_ASSERTIONS=1')
        if version_compare(self.version, '>=18'):
            args.append('-D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE')
        elif version_compare(self.version, '>=15'):
            args.append('-D_LIBCPP_ENABLE_ASSERTIONS=1')

        return args


class ArmLtdClangCPPCompiler(ClangCPPCompiler):

    id = 'armltdclang'


class AppleClangCPPCompiler(ClangCPPCompiler):

    _CPP23_VERSION = '>=13.0.0'
    # TODO: We don't know which XCode version will include LLVM 17 yet, so
    # use something absurd.
    _CPP26_VERSION = '>=99.0.0'


class EmscriptenCPPCompiler(EmscriptenMixin, ClangCPPCompiler):

    id = 'emscripten'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 defines: T.Optional[T.Dict[str, str]] = None,
                 full_version: T.Optional[str] = None):
        if not is_cross:
            raise MesonException('Emscripten compiler can only be used for cross compilation.')
        if not version_compare(version, '>=1.39.19'):
            raise MesonException('Meson requires Emscripten >= 1.39.19')
        ClangCPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                                  info, exe_wrapper=exe_wrapper, linker=linker,
                                  defines=defines, full_version=full_version)

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append(self._find_best_cpp_std(std.value))
        return args


class ArmclangCPPCompiler(ArmclangCompiler, CPPCompiler):
    '''
    Keil armclang
    '''

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        ArmclangCompiler.__init__(self)
        default_warn_args = ['-Wall', '-Winvalid-pch']
        self.warn_args = {'0': [],
                          '1': default_warn_args,
                          '2': default_warn_args + ['-Wextra'],
                          '3': default_warn_args + ['-Wextra', '-Wpedantic'],
                          'everything': ['-Weverything']}

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts.update({
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
        })
        std_opt = opts[key]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(['c++98', 'c++03', 'c++11', 'c++14', 'c++17'], gnu=True)
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append('-std=' + std.value)

        non_msvc_eh_options(options[key.evolve('eh')].value, args)

        return args

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []


class GnuCPPCompiler(_StdCPPLibMixin, GnuCompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 defines: T.Optional[T.Dict[str, str]] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        GnuCompiler.__init__(self, defines)
        default_warn_args = ['-Wall', '-Winvalid-pch']
        self.warn_args = {'0': [],
                          '1': default_warn_args,
                          '2': default_warn_args + ['-Wextra'],
                          '3': default_warn_args + ['-Wextra', '-Wpedantic'],
                          'everything': (default_warn_args + ['-Wextra', '-Wpedantic'] +
                                         self.supported_warn_args(gnu_common_warning_args) +
                                         self.supported_warn_args(gnu_cpp_warning_args))}

    def get_options(self) -> 'MutableKeyedOptionDictType':
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts = CPPCompiler.get_options(self)
        opts.update({
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
            key.evolve('rtti'): coredata.UserBooleanOption('Enable RTTI', True),
            key.evolve('debugstl'): coredata.UserBooleanOption(
                'STL debug mode',
                False,
            )
        })
        cppstd_choices = [
            'c++98', 'c++03', 'c++11', 'c++14', 'c++17', 'c++1z',
            'c++2a', 'c++20',
        ]
        if version_compare(self.version, '>=11.0.0'):
            cppstd_choices.append('c++23')
        if version_compare(self.version, '>=14.0.0'):
            cppstd_choices.append('c++26')
        std_opt = opts[key]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(cppstd_choices, gnu=True)
        if self.info.is_windows() or self.info.is_cygwin():
            opts.update({
                key.evolve('winlibs'): coredata.UserArrayOption(
                    'Standard Win libraries to link against',
                    gnu_winlibs,
                ),
            })
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append(self._find_best_cpp_std(std.value))

        non_msvc_eh_options(options[key.evolve('eh')].value, args)

        if not options[key.evolve('rtti')].value:
            args.append('-fno-rtti')

        if options[key.evolve('debugstl')].value:
            args.append('-D_GLIBCXX_DEBUG=1')
        return args

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        if self.info.is_windows() or self.info.is_cygwin():
            # without a typedict mypy can't understand this.
            key = OptionKey('winlibs', machine=self.for_machine, lang=self.language)
            libs = options[key].value.copy()
            assert isinstance(libs, list)
            for l in libs:
                assert isinstance(l, str)
            return libs
        return []

    def get_assert_args(self, disable: bool) -> T.List[str]:
        if disable:
            return ['-DNDEBUG']

        # XXX: This needs updating if/when GCC starts to support libc++.
        # It currently only does so via an experimental configure arg.
        return ['-D_GLIBCXX_ASSERTIONS=1']

    def get_pch_use_args(self, pch_dir: str, header: str) -> T.List[str]:
        return ['-fpch-preprocess', '-include', os.path.basename(header)]


class PGICPPCompiler(PGICompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        PGICompiler.__init__(self)


class NvidiaHPC_CPPCompiler(PGICompiler, CPPCompiler):

    id = 'nvidia_hpc'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        PGICompiler.__init__(self)


class ElbrusCPPCompiler(ElbrusCompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 defines: T.Optional[T.Dict[str, str]] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        ElbrusCompiler.__init__(self)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)

        cpp_stds = ['c++98']
        if version_compare(self.version, '>=1.20.00'):
            cpp_stds += ['c++03', 'c++0x', 'c++11']
        if version_compare(self.version, '>=1.21.00') and version_compare(self.version, '<1.22.00'):
            cpp_stds += ['c++14', 'c++1y']
        if version_compare(self.version, '>=1.22.00'):
            cpp_stds += ['c++14']
        if version_compare(self.version, '>=1.23.00'):
            cpp_stds += ['c++1y']
        if version_compare(self.version, '>=1.24.00'):
            cpp_stds += ['c++1z', 'c++17']
        if version_compare(self.version, '>=1.25.00'):
            cpp_stds += ['c++2a']
        if version_compare(self.version, '>=1.26.00'):
            cpp_stds += ['c++20']

        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts.update({
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
            key.evolve('debugstl'): coredata.UserBooleanOption(
                'STL debug mode',
                False,
            ),
        })
        std_opt = opts[key]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(cpp_stds, gnu=True)
        return opts

    # Elbrus C++ compiler does not have lchmod, but there is only linker warning, not compiler error.
    # So we should explicitly fail at this case.
    def has_function(self, funcname: str, prefix: str, env: 'Environment', *,
                     extra_args: T.Optional[T.List[str]] = None,
                     dependencies: T.Optional[T.List['Dependency']] = None) -> T.Tuple[bool, bool]:
        if funcname == 'lchmod':
            return False, False
        else:
            return super().has_function(funcname, prefix, env,
                                        extra_args=extra_args,
                                        dependencies=dependencies)

    # Elbrus C++ compiler does not support RTTI, so don't check for it.
    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append(self._find_best_cpp_std(std.value))

        non_msvc_eh_options(options[key.evolve('eh')].value, args)

        if options[key.evolve('debugstl')].value:
            args.append('-D_GLIBCXX_DEBUG=1')
        return args


class IntelCPPCompiler(IntelGnuLikeCompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        IntelGnuLikeCompiler.__init__(self)
        self.lang_header = 'c++-header'
        default_warn_args = ['-Wall', '-w3', '-Wpch-messages']
        self.warn_args = {'0': [],
                          '1': default_warn_args + ['-diag-disable:remark'],
                          '2': default_warn_args + ['-Wextra', '-diag-disable:remark'],
                          '3': default_warn_args + ['-Wextra', '-diag-disable:remark'],
                          'everything': default_warn_args + ['-Wextra']}

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        # Every Unix compiler under the sun seems to accept -std=c++03,
        # with the exception of ICC. Instead of preventing the user from
        # globally requesting C++03, we transparently remap it to C++98
        c_stds = ['c++98', 'c++03']
        g_stds = ['gnu++98', 'gnu++03']
        if version_compare(self.version, '>=15.0.0'):
            c_stds += ['c++11', 'c++14']
            g_stds += ['gnu++11']
        if version_compare(self.version, '>=16.0.0'):
            c_stds += ['c++17']
        if version_compare(self.version, '>=17.0.0'):
            g_stds += ['gnu++14']
        if version_compare(self.version, '>=19.1.0'):
            c_stds += ['c++2a']
            g_stds += ['gnu++2a']

        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts.update({
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
            key.evolve('rtti'): coredata.UserBooleanOption('Enable RTTI', True),
            key.evolve('debugstl'): coredata.UserBooleanOption('STL debug mode', False),
        })
        std_opt = opts[key]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(c_stds + g_stds)
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            remap_cpp03 = {
                'c++03': 'c++98',
                'gnu++03': 'gnu++98'
            }
            args.append('-std=' + remap_cpp03.get(std.value, std.value))
        if options[key.evolve('eh')].value == 'none':
            args.append('-fno-exceptions')
        if not options[key.evolve('rtti')].value:
            args.append('-fno-rtti')
        if options[key.evolve('debugstl')].value:
            args.append('-D_GLIBCXX_DEBUG=1')
        return args

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []


class IntelLLVMCPPCompiler(ClangCPPCompiler):

    id = 'intel-llvm'


class VisualStudioLikeCPPCompilerMixin(CompilerMixinBase):

    """Mixin for C++ specific method overrides in MSVC-like compilers."""

    VC_VERSION_MAP = {
        'none': (True, None),
        'vc++11': (True, 11),
        'vc++14': (True, 14),
        'vc++17': (True, 17),
        'vc++20': (True, 20),
        'vc++latest': (True, "latest"),
        'c++11': (False, 11),
        'c++14': (False, 14),
        'c++17': (False, 17),
        'c++20': (False, 20),
        'c++latest': (False, "latest"),
    }

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        # need a typeddict for this
        key = OptionKey('winlibs', machine=self.for_machine, lang=self.language)
        return T.cast('T.List[str]', options[key].value[:])

    def _get_options_impl(self, opts: 'MutableKeyedOptionDictType', cpp_stds: T.List[str]) -> 'MutableKeyedOptionDictType':
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts.update({
            key.evolve('eh'): coredata.UserComboOption(
                'C++ exception handling type.',
                ['none', 'default', 'a', 's', 'sc'],
                'default',
            ),
            key.evolve('rtti'): coredata.UserBooleanOption('Enable RTTI', True),
            key.evolve('winlibs'): coredata.UserArrayOption(
                'Windows libs to link against.',
                msvc_winlibs,
            ),
        })
        std_opt = opts[key]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(cpp_stds)
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)

        eh = options[key.evolve('eh')]
        if eh.value == 'default':
            args.append('/EHsc')
        elif eh.value == 'none':
            args.append('/EHs-c-')
        else:
            args.append('/EH' + eh.value)

        if not options[key.evolve('rtti')].value:
            args.append('/GR-')

        permissive, ver = self.VC_VERSION_MAP[options[key].value]

        if ver is not None:
            args.append(f'/std:c++{ver}')

        if not permissive:
            args.append('/permissive-')

        return args

    def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
        # XXX: this is a hack because so much GnuLike stuff is in the base CPPCompiler class.
        return Compiler.get_compiler_check_args(self, mode)


class CPP11AsCPP14Mixin(CompilerMixinBase):

    """Mixin class for VisualStudio and ClangCl to replace C++11 std with C++14.

    This is a limitation of Clang and MSVC that ICL doesn't share.
    """

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        # Note: there is no explicit flag for supporting C++11; we attempt to do the best we can
        # which means setting the C++ standard version to C++14, in compilers that support it
        # (i.e., after VS2015U3)
        # if one is using anything before that point, one cannot set the standard.
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        if options[key].value in {'vc++11', 'c++11'}:
            mlog.warning(self.id, 'does not support C++11;',
                         'attempting best effort; setting the standard to C++14',
                         once=True, fatal=False)
            # Don't mutate anything we're going to change, we need to use
            # deepcopy since we're messing with members, and we can't simply
            # copy the members because the option proxy doesn't support it.
            options = copy.deepcopy(options)
            if options[key].value == 'vc++11':
                options[key].value = 'vc++14'
            else:
                options[key].value = 'c++14'
        return super().get_option_compile_args(options)


class VisualStudioCPPCompiler(CPP11AsCPP14Mixin, VisualStudioLikeCPPCompilerMixin, MSVCCompiler, CPPCompiler):

    id = 'msvc'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice,
                 is_cross: bool, info: 'MachineInfo', target: str,
                 exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        MSVCCompiler.__init__(self, target)

        # By default, MSVC has a broken __cplusplus define that pretends to be c++98:
        # https://docs.microsoft.com/en-us/cpp/build/reference/zc-cplusplus?view=msvc-160
        # Pass the flag to enable a truthful define, if possible.
        if version_compare(self.version, '>= 19.14.26428'):
            self.always_args = self.always_args + ['/Zc:__cplusplus']

    def get_options(self) -> 'MutableKeyedOptionDictType':
        cpp_stds = ['none', 'c++11', 'vc++11']
        # Visual Studio 2015 and later
        if version_compare(self.version, '>=19'):
            cpp_stds.extend(['c++14', 'c++latest', 'vc++latest'])
        # Visual Studio 2017 and later
        if version_compare(self.version, '>=19.11'):
            cpp_stds.extend(['vc++14', 'c++17', 'vc++17'])
        if version_compare(self.version, '>=19.29'):
            cpp_stds.extend(['c++20', 'vc++20'])
        return self._get_options_impl(super().get_options(), cpp_stds)

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        if options[key].value != 'none' and version_compare(self.version, '<19.00.24210'):
            mlog.warning('This version of MSVC does not support cpp_std arguments', fatal=False)
            options = copy.copy(options)
            options[key].value = 'none'

        args = super().get_option_compile_args(options)

        if version_compare(self.version, '<19.11'):
            try:
                i = args.index('/permissive-')
            except ValueError:
                return args
            del args[i]
        return args

class ClangClCPPCompiler(CPP11AsCPP14Mixin, VisualStudioLikeCPPCompilerMixin, ClangClCompiler, CPPCompiler):

    id = 'clang-cl'

    def __init__(self, exelist: T.List[str], version: str, for_machine: MachineChoice,
                 is_cross: bool, info: 'MachineInfo', target: str,
                 exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, [], exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        ClangClCompiler.__init__(self, target)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        cpp_stds = ['none', 'c++11', 'vc++11', 'c++14', 'vc++14', 'c++17', 'vc++17', 'c++20', 'vc++20', 'c++latest']
        return self._get_options_impl(super().get_options(), cpp_stds)


class IntelClCPPCompiler(VisualStudioLikeCPPCompilerMixin, IntelVisualStudioLikeCompiler, CPPCompiler):

    def __init__(self, exelist: T.List[str], version: str, for_machine: MachineChoice,
                 is_cross: bool, info: 'MachineInfo', target: str,
                 exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, [], exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        IntelVisualStudioLikeCompiler.__init__(self, target)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        # This has only been tested with version 19.0,
        cpp_stds = ['none', 'c++11', 'vc++11', 'c++14', 'vc++14', 'c++17', 'vc++17', 'c++latest']
        return self._get_options_impl(super().get_options(), cpp_stds)

    def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
        # XXX: this is a hack because so much GnuLike stuff is in the base CPPCompiler class.
        return IntelVisualStudioLikeCompiler.get_compiler_check_args(self, mode)


class IntelLLVMClCPPCompiler(IntelClCPPCompiler):

    id = 'intel-llvm-cl'


class ArmCPPCompiler(ArmCompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        ArmCompiler.__init__(self)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        std_opt = opts[OptionKey('std', machine=self.for_machine, lang=self.language)]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(['c++03', 'c++11'])
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value == 'c++11':
            args.append('--cpp11')
        elif std.value == 'c++03':
            args.append('--cpp')
        return args

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []

    def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
        return []


class CcrxCPPCompiler(CcrxCompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        CcrxCompiler.__init__(self)

    # Override CCompiler.get_always_args
    def get_always_args(self) -> T.List[str]:
        return ['-nologo', '-lang=cpp']

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []

    def get_compile_only_args(self) -> T.List[str]:
        return []

    def get_output_args(self, outputname: str) -> T.List[str]:
        return [f'-output=obj={outputname}']

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []

    def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
        return []

class TICPPCompiler(TICompiler, CPPCompiler):
    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice, is_cross: bool,
                 info: 'MachineInfo', exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        TICompiler.__init__(self)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        std_opt = opts[OptionKey('std', machine=self.for_machine, lang=self.language)]
        assert isinstance(std_opt, coredata.UserStdOption), 'for mypy'
        std_opt.set_versions(['c++03'])
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        std = options[key]
        if std.value != 'none':
            args.append('--' + std.value)
        return args

    def get_always_args(self) -> T.List[str]:
        return []

    def get_option_link_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        return []

class C2000CPPCompiler(TICPPCompiler):
    # Required for backwards compat with projects created before ti-cgt support existed
    id = 'c2000'

class MetrowerksCPPCompilerARM(MetrowerksCompiler, CPPCompiler):
    id = 'mwccarm'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice,
                 is_cross: bool, info: 'MachineInfo',
                 exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        MetrowerksCompiler.__init__(self)

    def get_instruction_set_args(self, instruction_set: str) -> T.Optional[T.List[str]]:
        return mwccarm_instruction_set_args.get(instruction_set, None)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts[key].choices = ['none']
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        std = options[OptionKey('std', machine=self.for_machine, lang=self.language)]
        if std.value != 'none':
            args.append('-lang')
            args.append(std.value)
        return args

class MetrowerksCPPCompilerEmbeddedPowerPC(MetrowerksCompiler, CPPCompiler):
    id = 'mwcceppc'

    def __init__(self, ccache: T.List[str], exelist: T.List[str], version: str, for_machine: MachineChoice,
                 is_cross: bool, info: 'MachineInfo',
                 exe_wrapper: T.Optional['ExternalProgram'] = None,
                 linker: T.Optional['DynamicLinker'] = None,
                 full_version: T.Optional[str] = None):
        CPPCompiler.__init__(self, ccache, exelist, version, for_machine, is_cross,
                             info, exe_wrapper, linker=linker, full_version=full_version)
        MetrowerksCompiler.__init__(self)

    def get_instruction_set_args(self, instruction_set: str) -> T.Optional[T.List[str]]:
        return mwcceppc_instruction_set_args.get(instruction_set, None)

    def get_options(self) -> 'MutableKeyedOptionDictType':
        opts = CPPCompiler.get_options(self)
        key = OptionKey('std', machine=self.for_machine, lang=self.language)
        opts[key].choices = ['none']
        return opts

    def get_option_compile_args(self, options: 'KeyedOptionDictType') -> T.List[str]:
        args: T.List[str] = []
        std = options[OptionKey('std', machine=self.for_machine, lang=self.language)]
        if std.value != 'none':
            args.append('-lang ' + std.value)
        return args