meson/mesonbuild/compilers.py

# Copyright 2012-2014 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import subprocess, os.path
import tempfile
from .import mesonlib
from . import mlog
from .mesonlib import MesonException
from . import coredata

"""This file contains the data files of all compilers Meson knows
about. To support a new compiler, add its information below.
Also add corresponding autodetection code in environment.py."""

header_suffixes = ['h', 'hh', 'hpp', 'hxx', 'H', 'ipp', 'moc', 'vapi']
cpp_suffixes = ['cc', 'cpp', 'cxx', 'h', 'hh', 'hpp', 'ipp', 'hxx', 'c++']
c_suffixes = ['c']
clike_suffixes = c_suffixes + cpp_suffixes
obj_suffixes = ['o', 'obj', 'res']
lib_suffixes = ['a', 'lib', 'dll', 'dylib', 'so']

def is_header(fname):
    if hasattr(fname, 'fname'):
        fname = fname.fname
    suffix = fname.split('.')[-1]
    return suffix in header_suffixes

def is_source(fname):
    if hasattr(fname, 'fname'):
        fname = fname.fname
    suffix = fname.split('.')[-1]
    return suffix in clike_suffixes

def is_object(fname):
    if hasattr(fname, 'fname'):
        fname = fname.fname
    suffix = fname.split('.')[-1]
    return suffix in obj_suffixes

def is_library(fname):
    if hasattr(fname, 'fname'):
        fname = fname.fname
    suffix = fname.split('.')[-1]
    return suffix in lib_suffixes

gnulike_buildtype_args = {'plain' : [],
                          # -O0 is passed for improved debugging information with gcc
                          # See https://github.com/mesonbuild/meson/pull/509
                          'debug' : ['-O0', '-g'],
                          'debugoptimized' : ['-O2', '-g'],
                          'release' : ['-O3']}

msvc_buildtype_args = {'plain' : [],
                       'debug' : ["/MDd", "/ZI", "/Ob0", "/Od", "/RTC1"],
                       'debugoptimized' : ["/MD", "/Zi", "/O2", "/Ob1"],
                       'release' : ["/MD", "/O2", "/Ob2"]}

gnulike_buildtype_linker_args = {}


if mesonlib.is_osx():
    gnulike_buildtype_linker_args.update({'plain' : [],
                                          'debug' : [],
                                          'debugoptimized' : [],
                                          'release' : [],
                                         })
else:
    gnulike_buildtype_linker_args.update({'plain' : [],
                                          'debug' : [],
                                          'debugoptimized' : [],
                                          'release' : ['-Wl,-O1'],
                                         })

msvc_buildtype_linker_args = {'plain' : [],
                              'debug' : [],
                              'debugoptimized' : [],
                              'release' : []}

java_buildtype_args = {'plain' : [],
                       'debug' : ['-g'],
                       'debugoptimized' : ['-g'],
                       'release' : []}

rust_buildtype_args = {'plain' : [],
                       'debug' : ['-g'],
                       'debugoptimized' : ['-g', '--opt-level', '2'],
                       'release' : ['--opt-level', '3']}

mono_buildtype_args = {'plain' : [],
                       'debug' : ['-debug'],
                       'debugoptimized': ['-debug', '-optimize+'],
                       'release' : ['-optimize+']}

swift_buildtype_args = {'plain' : [],
                        'debug' : ['-g'],
                        'debugoptimized': ['-g', '-O'],
                        'release' : ['-O']}

gnu_winlibs = ['-lkernel32', '-luser32', '-lgdi32', '-lwinspool', '-lshell32',
               '-lole32', '-loleaut32', '-luuid', '-lcomdlg32', '-ladvapi32']

msvc_winlibs = ['kernel32.lib', 'user32.lib', 'gdi32.lib',
                'winspool.lib', 'shell32.lib', 'ole32.lib', 'oleaut32.lib',
                'uuid.lib', 'comdlg32.lib', 'advapi32.lib']


base_options = {
                'b_pch': coredata.UserBooleanOption('b_pch', 'Use precompiled headers', True),
                'b_lto': coredata.UserBooleanOption('b_lto', 'Use link time optimization', False),
                'b_sanitize': coredata.UserComboOption('b_sanitize',
                                                       'Code sanitizer to use',
                                                       ['none', 'address', 'thread', 'undefined', 'memory'],
                                                       'none'),
                'b_lundef': coredata.UserBooleanOption('b_lundef', 'Use -Wl,--no-undefined when linking', True),
                'b_pgo': coredata.UserComboOption('b_pgo', 'Use profile guide optimization',
                                                  ['off', 'generate', 'use'],
                                                  'off'),
                'b_coverage': coredata.UserBooleanOption('b_coverage',
                                                         'Enable coverage tracking.',
                                                         False),
                }

def sanitizer_compile_args(value):
    if value == 'none':
        return []
    args = ['-fsanitize=' + value]
    if value == 'address':
        args.append('-fno-omit-frame-pointer')
    return args

def sanitizer_link_args(value):
    if value == 'none':
        return []
    args = ['-fsanitize=' + value]
    return args

def get_base_compile_args(options, compiler):
    args = []
    # FIXME, gcc/clang specific.
    try:
        if options['b_lto'].value:
            args.append('-flto')
    except KeyError:
        pass
    try:
        args += sanitizer_compile_args(options['b_sanitize'].value)
    except KeyError:
        pass
    try:
        pgo_val = options['b_pgo'].value
        if pgo_val == 'generate':
            args.append('-fprofile-generate')
        elif pgo_val == 'use':
            args.append('-fprofile-use')
    except KeyError:
        pass
    try:
        if options['b_coverage'].value:
            args += compiler.get_coverage_args()
    except KeyError:
        pass
    return args

def get_base_link_args(options, linker):
    args = []
    # FIXME, gcc/clang specific.
    try:
        if options['b_lto'].value:
            args.append('-flto')
    except KeyError:
        pass
    try:
        args += sanitizer_link_args(options['b_sanitize'].value)
    except KeyError:
        pass
    try:
        pgo_val = options['b_pgo'].value
        if pgo_val == 'generate':
            args.append('-fprofile-generate')
        elif pgo_val == 'use':
            args.append('-fprofile-use')
    except KeyError:
        pass
    try:
        if options['b_lundef'].value:
            args.append('-Wl,--no-undefined')
    except KeyError:
        pass
    try:
        if options['b_coverage'].value:
            args += linker.get_coverage_link_args()
    except KeyError:
        pass
    return args

def build_unix_rpath_args(build_dir, rpath_paths, install_rpath):
        if len(rpath_paths) == 0 and len(install_rpath) == 0:
            return []
        paths = ':'.join([os.path.join(build_dir, p) for p in rpath_paths])
        if len(paths) < len(install_rpath):
            padding = 'X'*(len(install_rpath) - len(paths))
            if len(paths) == 0:
                paths = padding
            else:
                paths = paths + ':' + padding
        return ['-Wl,-rpath,' + paths]

class EnvironmentException(MesonException):
    def __init(self, *args, **kwargs):
        Exception.__init__(self, *args, **kwargs)

class CrossNoRunException(MesonException):
    def __init(self, *args, **kwargs):
        Exception.__init__(self, *args, **kwargs)

class RunResult():
    def __init__(self, compiled, returncode=999, stdout='UNDEFINED', stderr='UNDEFINED'):
        self.compiled = compiled
        self.returncode = returncode
        self.stdout = stdout
        self.stderr = stderr

class Compiler():
    def __init__(self, exelist, version):
        if type(exelist) == type(''):
            self.exelist = [exelist]
        elif type(exelist) == type([]):
            self.exelist = exelist
        else:
            raise TypeError('Unknown argument to Compiler')
        self.version = version
        self.base_options = []

    def get_always_args(self):
        return []

    def get_linker_always_args(self):
        return []

    def get_options(self):
        return {} # build afresh every time

    def get_option_compile_args(self, options):
        return []

    def get_option_link_args(self, options):
        return []

    def has_header(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support header checks.' % self.language)

    def has_header_symbol(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support header symbol checks.' % self.language)

    def compiles(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support compile checks.' % self.language)

    def links(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support link checks.' % self.language)

    def run(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support run checks.' % self.language)

    def sizeof(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support sizeof checks.' % self.language)

    def alignment(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support alignment checks.' % self.language)

    def has_function(self, *args, **kwargs):
        raise EnvironmentException('Language %s does not support function checks.' % self.language)

    def unix_link_flags_to_native(self, args):
        "Always returns a copy that can be independently mutated"
        return args[:]

    def unix_compile_flags_to_native(self, args):
        "Always returns a copy that can be independently mutated"
        return args[:]

    def find_library(self, *args, **kwargs):
        raise EnvironmentException('Language {} does not support library finding.'.format(self.language))

    def get_library_dirs(self):
        return []

    def has_argument(self, arg):
        raise EnvironmentException('Language {} does not support has_arg.'.format(self.language))

    def get_cross_extra_flags(self, environment, *, compile, link):
        extra_flags = []
        if self.is_cross and environment:
            if 'properties' in environment.cross_info.config:
                lang_args_key = self.language + '_args'
                if compile:
                    extra_flags += environment.cross_info.config['properties'].get(lang_args_key, [])
                lang_link_args_key = self.language + '_link_args'
                if link:
                    extra_flags += environment.cross_info.config['properties'].get(lang_link_args_key, [])
        return extra_flags

class CCompiler(Compiler):
    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version)
        self.language = 'c'
        self.default_suffix = 'c'
        self.id = 'unknown'
        self.is_cross = is_cross
        if isinstance(exe_wrapper, str):
            self.exe_wrapper = [exe_wrapper]
        else:
            self.exe_wrapper = exe_wrapper

    def needs_static_linker(self):
        return True # When compiling static libraries, so yes.

    def get_always_args(self):
        return []

    def get_no_stdinc_args(self):
        return ['-nostdinc']

    def get_no_stdlib_link_args(self):
        return ['-nostdlib']

    def get_warn_args(self, level):
        return self.warn_args[level]

    def get_soname_args(self, shlib_name, path, soversion):
        return []

    def split_shlib_to_parts(self, fname):
        return (None, fname)

    # The default behaviour is this, override in
    # OSX and MSVC.
    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return build_unix_rpath_args(build_dir, rpath_paths, install_rpath)

    def get_id(self):
        return self.id

    def get_dependency_gen_args(self, outtarget, outfile):
        return ['-MMD', '-MQ', outtarget, '-MF', outfile]

    def depfile_for_object(self, objfile):
        return objfile + '.' + self.get_depfile_suffix()

    def get_depfile_suffix(self):
        return 'd'

    def get_language(self):
        return self.language

    def get_default_suffix(self):
        return self.default_suffix

    def get_exelist(self):
        return self.exelist[:]

    def get_linker_exelist(self):
        return self.exelist[:]

    def get_compile_only_args(self):
        return ['-c']

    def get_no_optimization_args(self):
        return ['-O0']

    def get_output_args(self, target):
        return ['-o', target]

    def get_linker_output_args(self, outputname):
        return ['-o', outputname]

    def get_coverage_args(self):
        return ['--coverage']

    def get_coverage_link_args(self):
        return ['-lgcov']

    def get_werror_args(self):
        return ['-Werror']

    def get_std_exe_link_args(self):
        return []

    def get_include_args(self, path, is_system):
        if path == '':
            path = '.'
        if is_system:
            return ['-isystem', path]
        return ['-I' + path]

    def get_std_shared_lib_link_args(self):
        return ['-shared']

    def get_library_dirs(self):
        output = subprocess.Popen(self.exelist + ['--print-search-dirs'], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
        (stdo, _) = output.communicate()
        stdo = stdo.decode('utf-8')
        for line in stdo.split('\n'):
            if line.startswith('libraries:'):
                libstr = line.split('=', 1)[1]
                return libstr.split(':')
        return []

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix == 'c' or suffix == 'h':
            return True
        return False

    def get_pic_args(self):
        return ['-fPIC']

    def name_string(self):
        return ' '.join(self.exelist)

    def get_pch_use_args(self, pch_dir, header):
        return ['-include', os.path.split(header)[-1]]

    def get_pch_name(self, header_name):
        return os.path.split(header_name)[-1] + '.' + self.get_pch_suffix()

    def get_linker_search_args(self, dirname):
        return ['-L'+dirname]

    def sanity_check_impl(self, work_dir, environment, sname, code):
        mlog.debug('Sanity testing ' + self.language + ' compiler:', ' '.join(self.exelist))
        mlog.debug('Is cross compiler: %s.' % str(self.is_cross))

        extra_flags = []
        source_name = os.path.join(work_dir, sname)
        binname = sname.rsplit('.', 1)[0]
        if self.is_cross:
            binname += '_cross'
            if self.exe_wrapper is None:
                # Linking cross built apps is painful. You can't really
                # tell if you should use -nostdlib or not and for example
                # on OSX the compiler binary is the same but you need
                # a ton of compiler flags to differentiate between
                # arm and x86_64. So just compile.
                extra_flags += self.get_cross_extra_flags(environment, compile=True, link=False)
                extra_flags += self.get_compile_only_args()
            else:
                extra_flags += self.get_cross_extra_flags(environment, compile=True, link=True)
        # Is a valid executable output for all toolchains and platforms
        binname += '.exe'
        # Write binary check source
        binary_name = os.path.join(work_dir, binname)
        ofile = open(source_name, 'w')
        ofile.write(code)
        ofile.close()
        # Compile sanity check
        cmdlist = self.exelist + extra_flags + [source_name] + self.get_output_args(binary_name)
        pc = subprocess.Popen(cmdlist, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=work_dir)
        (stdo, stde) = pc.communicate()
        stdo = stdo.decode()
        stde = stde.decode()
        mlog.debug('Sanity check compiler command line:', ' '.join(cmdlist))
        mlog.debug('Sanity check compile stdout:')
        mlog.debug(stdo)
        mlog.debug('-----\nSanity check compile stderr:')
        mlog.debug(stde)
        mlog.debug('-----')
        if pc.returncode != 0:
            raise EnvironmentException('Compiler {0} can not compile programs.'.format(self.name_string()))
        # Run sanity check
        if self.is_cross:
            if self.exe_wrapper is None:
                # Can't check if the binaries run so we have to assume they do
                return
            cmdlist = self.exe_wrapper + [binary_name]
        else:
            cmdlist = [binary_name]
        mlog.debug('Running test binary command: ' + ' '.join(cmdlist))
        pe = subprocess.Popen(cmdlist)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by {0} compiler {1} are not runnable.'.format(self.language, self.name_string()))

    def sanity_check(self, work_dir, environment):
        code = 'int main(int argc, char **argv) { int class=0; return class; }\n'
        return self.sanity_check_impl(work_dir, environment, 'sanitycheckc.c', code)

    def has_header(self, hname, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        templ = '''#include<%s>
int someSymbolHereJustForFun;
'''
        return self.compiles(templ % hname, env, extra_args)

    def has_header_symbol(self, hname, symbol, prefix, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        templ = '''{2}
#include <{0}>
int main () {{ {1}; }}'''
        # Pass -O0 to ensure that the symbol isn't optimized away
        extra_args += self.get_no_optimization_args()
        return self.compiles(templ.format(hname, symbol, prefix), env, extra_args)

    def compile(self, code, srcname, extra_args=None):
        if extra_args is None:
            extra_args = []
        commands = self.get_exelist()
        commands.append(srcname)
        commands += extra_args
        mlog.debug('Running compile:')
        mlog.debug('Command line: ', ' '.join(commands))
        mlog.debug('Code:\n', code)
        p = subprocess.Popen(commands, cwd=os.path.split(srcname)[0], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        (stde, stdo) = p.communicate()
        stde = stde.decode()
        stdo = stdo.decode()
        mlog.debug('Compiler stdout:\n', stdo)
        mlog.debug('Compiler stderr:\n', stde)
        os.remove(srcname)
        return p

    def compiles(self, code, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        if isinstance(extra_args, str):
            extra_args = [extra_args]
        suflen = len(self.default_suffix)
        (fd, srcname) = tempfile.mkstemp(suffix='.'+self.default_suffix)
        os.close(fd)
        ofile = open(srcname, 'w')
        ofile.write(code)
        ofile.close()
        # Convert flags to the native type of the selected compiler
        args = self.unix_link_flags_to_native(extra_args)
        # Read c_args/cpp_args/etc from the cross-info file (if needed)
        args += self.get_cross_extra_flags(env, compile=True, link=False)
        # We only want to compile; not link
        args += self.get_compile_only_args()
        p = self.compile(code, srcname, args)
        try:
            trial = srcname[:-suflen] + 'o'
            os.remove(trial)
        except FileNotFoundError:
            pass
        try:
            os.remove(srcname[:-suflen] + 'obj')
        except FileNotFoundError:
            pass
        return p.returncode == 0

    def links(self, code, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        (fd, srcname) = tempfile.mkstemp(suffix='.'+self.default_suffix)
        os.close(fd)
        (fd, dstname) = tempfile.mkstemp()
        os.close(fd)
        ofile = open(srcname, 'w')
        ofile.write(code)
        ofile.close()
        # Convert flags to the native type of the selected compiler
        args = self.unix_link_flags_to_native(extra_args)
        # Need to add buildtype args to select the CRT to use with MSVC
        # This is needed especially while trying to link with static libraries
        # since MSVC won't auto-select a CRT for us in that case and will error
        # out asking us to select one.
        args += self.get_buildtype_args('debug')
        # Read c_args/c_link_args/cpp_args/cpp_link_args/etc from the cross-info file (if needed)
        args += self.get_cross_extra_flags(env, compile=True, link=True)
        # Arguments specifying the output filename
        args += self.get_output_args(dstname)
        p = self.compile(code, srcname, args)
        try:
            os.remove(dstname)
        except FileNotFoundError:
            pass
        return p.returncode == 0

    def run(self, code, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        mlog.debug('Running code:\n\n', code)
        if self.is_cross and self.exe_wrapper is None:
            raise CrossNoRunException('Can not run test applications in this cross environment.')
        (fd, srcname) = tempfile.mkstemp(suffix='.'+self.default_suffix)
        os.close(fd)
        ofile = open(srcname, 'w')
        ofile.write(code)
        ofile.close()
        # Convert flags to the native type of the selected compiler
        args = self.unix_link_flags_to_native(extra_args)
        # Same reasoning as self.links() above
        args += self.get_buildtype_args('debug')
        # Read c_link_args/cpp_link_args/etc from the cross-info file
        args += self.get_cross_extra_flags(env, compile=True, link=True)
        # Create command list
        exename = srcname + '.exe' # Is guaranteed to be executable on every platform.
        commands = self.get_exelist() + args
        commands.append(srcname)
        commands += self.get_output_args(exename)
        p = subprocess.Popen(commands, cwd=os.path.split(srcname)[0], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        (stdo, stde) = p.communicate()
        stde = stde.decode()
        stdo = stdo.decode()
        mlog.debug('Compiler stdout:\n', stdo)
        mlog.debug('Compiler stderr:\n', stde)
        os.remove(srcname)
        if p.returncode != 0:
            return RunResult(False)
        if self.is_cross:
            cmdlist = self.exe_wrapper + [exename]
        else:
            cmdlist = exename
        try:
            pe = subprocess.Popen(cmdlist, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except Exception as e:
            mlog.debug('Could not run: %s (error: %s)\n' % (cmdlist, e))
            return RunResult(False)

        (so, se) = pe.communicate()
        so = so.decode()
        se = se.decode()
        mlog.debug('Program stdout:\n', so)
        mlog.debug('Program stderr:\n', se)
        try:
            os.remove(exename)
        except PermissionError:
            # On Windows antivirus programs and the like hold
            # on to files so they can't be deleted. There's not
            # much to do in this case.
            pass
        return RunResult(True, pe.returncode, so, se)

    def cross_sizeof(self, element, prefix, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        element_exists_templ = '''#include <stdio.h>
{0}
int main(int argc, char **argv) {{
    {1} something;
}}
'''
        templ = '''#include <stdio.h>
%s
int temparray[%d-sizeof(%s)];
'''
        extra_args += self.get_no_optimization_args()
        if not self.compiles(element_exists_templ.format(prefix, element), env, extra_args):
            return -1
        for i in range(1, 1024):
            code = templ % (prefix, i, element)
            if self.compiles(code, env, extra_args):
                if self.id == 'msvc':
                    # MSVC refuses to construct an array of zero size, so
                    # the test only succeeds when i is sizeof(element) + 1
                    return i - 1
                return i
        raise EnvironmentException('Cross checking sizeof overflowed.')

    def sizeof(self, element, prefix, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        if self.is_cross:
            return self.cross_sizeof(element, prefix, env, extra_args)
        templ = '''#include<stdio.h>
%s

int main(int argc, char **argv) {
    printf("%%ld\\n", (long)(sizeof(%s)));
    return 0;
};
'''
        res = self.run(templ % (prefix, element), env, extra_args)
        if not res.compiled:
            return -1
        if res.returncode != 0:
            raise EnvironmentException('Could not run sizeof test binary.')
        return int(res.stdout)

    def cross_alignment(self, typename, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        type_exists_templ = '''#include <stdio.h>
int main(int argc, char **argv) {{
    {0} something;
}}
'''
        templ = '''#include<stddef.h>
struct tmp {
  char c;
  %s target;
};

int testarray[%d-offsetof(struct tmp, target)];
'''
        extra_args += self.get_no_optimization_args()
        if not self.compiles(type_exists_templ.format(typename), env, extra_args):
            return -1
        for i in range(1, 1024):
            code = templ % (typename, i)
            if self.compiles(code, env, extra_args):
                if self.id == 'msvc':
                    # MSVC refuses to construct an array of zero size, so
                    # the test only succeeds when i is sizeof(element) + 1
                    return i - 1
                return i
        raise EnvironmentException('Cross checking offsetof overflowed.')

    def alignment(self, typename, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        if self.is_cross:
            return self.cross_alignment(typename, env, extra_args)
        templ = '''#include<stdio.h>
#include<stddef.h>

struct tmp {
  char c;
  %s target;
};

int main(int argc, char **argv) {
  printf("%%d", (int)offsetof(struct tmp, target));
  return 0;
}
'''
        res = self.run(templ % typename, env, extra_args)
        if not res.compiled:
            raise EnvironmentException('Could not compile alignment test.')
        if res.returncode != 0:
            raise EnvironmentException('Could not run alignment test binary.')
        align = int(res.stdout)
        if align == 0:
            raise EnvironmentException('Could not determine alignment of %s. Sorry. You might want to file a bug.' % typename)
        return align

    def has_function(self, funcname, prefix, env, extra_args=None):
        """
        First, this function looks for the symbol in the default libraries
        provided by the compiler (stdlib + a few others usually). If that
        fails, it checks if any of the headers specified in the prefix provide
        an implementation of the function, and if that fails, it checks if it's
        implemented as a compiler-builtin.
        """
        if extra_args is None:
            extra_args = []
        # Define the symbol to something else in case it is defined by the
        # includes or defines listed by the user `{0}` or by the compiler.
        # Then, undef the symbol to get rid of it completely.
        templ = '''
        #define {1} meson_disable_define_of_{1}
        #include <limits.h>
        {0}
        #undef {1}
        '''

        # Override any GCC internal prototype and declare our own definition for
        # the symbol. Use char because that's unlikely to be an actual return
        # value for a function which ensures that we override the definition.
        templ += '''
        #ifdef __cplusplus
        extern "C"
        #endif
        char {1} ();
        '''

        # glibc defines functions that are not available on Linux as stubs that
        # fail with ENOSYS (such as e.g. lchmod). In this case we want to fail
        # instead of detecting the stub as a valid symbol.
        # We always include limits.h above to ensure that these are defined for
        # stub functions.
        stubs_fail = '''
        #if defined __stub_{1} || defined __stub___{1}
        fail fail fail this function is not going to work
        #endif
        '''
        templ += stubs_fail

        # And finally the actual function call
        templ += '''
        int
        main ()
        {{
          return {1} ();
        }}'''
        varname = 'has function ' + funcname
        varname = varname.replace(' ', '_')
        if self.is_cross:
            val = env.cross_info.config['properties'].get(varname, None)
            if val is not None:
                if isinstance(val, bool):
                    return val
                raise EnvironmentException('Cross variable {0} is not a boolean.'.format(varname))
        if self.links(templ.format(prefix, funcname), env, extra_args):
            return True
        # Add -O0 to ensure that the symbol isn't optimized away by the compiler
        extra_args += self.get_no_optimization_args()
        # Sometimes the implementation is provided by the header, or the header
        # redefines the symbol to be something else. In that case, we want to
        # still detect the function. We still want to fail if __stub_foo or
        # _stub_foo are defined, of course.
        header_templ = '#include <limits.h>\n{0}\n' + stubs_fail + '\nint main() {{ {1}; }}'
        if self.links(header_templ.format(prefix, funcname), env, extra_args):
            return True
        # Some functions like alloca() are defined as compiler built-ins which
        # are inlined by the compiler, so test for that instead. Built-ins are
        # special functions that ignore all includes and defines, so we just
        # directly try to link via main().
        return self.links('int main() {{ {0}; }}'.format('__builtin_' + funcname), env, extra_args)

    def has_member(self, typename, membername, prefix, env, extra_args=None):
        if extra_args is None:
            extra_args = []
        templ = '''%s
void bar() {
    %s foo;
    foo.%s;
};
'''
        return self.compiles(templ % (prefix, typename, membername), env, extra_args)

    def has_type(self, typename, prefix, env, extra_args):
        templ = '''%s
void bar() {
    sizeof(%s);
};
'''
        return self.compiles(templ % (prefix, typename), env, extra_args)

    def find_library(self, libname, env, extra_dirs):
        # First try if we can just add the library as -l.
        code = '''int main(int argc, char **argv) {
    return 0;
}
        '''
        if extra_dirs and isinstance(extra_dirs, str):
            extra_dirs = [extra_dirs]
        # Gcc + co seem to prefer builtin lib dirs to -L dirs.
        # Only try to find std libs if no extra dirs specified.
        if len(extra_dirs) == 0:
            args = ['-l' + libname]
            if self.links(code, env, extra_args=args):
                return args
        # Not found? Try to find the library file itself.
        extra_dirs += self.get_library_dirs()
        suffixes = ['so', 'dylib', 'lib', 'dll', 'a']
        for d in extra_dirs:
            for suffix in suffixes:
                trial = os.path.join(d, 'lib' + libname + '.' + suffix)
                if os.path.isfile(trial):
                    return trial
                trial2 = os.path.join(d, libname + '.' + suffix)
                if os.path.isfile(trial2):
                    return trial2
        return None

    def thread_flags(self):
        return ['-pthread']

    def thread_link_flags(self):
        return ['-pthread']

    def has_argument(self, arg, env):
        return self.compiles('int i;\n', env, extra_args=arg)

class CPPCompiler(CCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrap):
        CCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.language = 'cpp'
        self.default_suffix = 'cpp'

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix in cpp_suffixes:
            return True
        return False

    def sanity_check(self, work_dir, environment):
        code = 'class breakCCompiler;int main(int argc, char **argv) { return 0; }\n'
        return self.sanity_check_impl(work_dir, environment, 'sanitycheckcpp.cc', code)

class ObjCCompiler(CCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrap):
        CCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.language = 'objc'
        self.default_suffix = 'm'

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix == 'm' or suffix == 'h':
            return True
        return False

    def sanity_check(self, work_dir, environment):
        # TODO try to use sanity_check_impl instead of duplicated code
        source_name = os.path.join(work_dir, 'sanitycheckobjc.m')
        binary_name = os.path.join(work_dir, 'sanitycheckobjc')
        extra_flags = self.get_cross_extra_flags(environment, compile=True, link=False)
        if self.is_cross:
            extra_flags += self.get_compile_only_args()
        ofile = open(source_name, 'w')
        ofile.write('#import<stdio.h>\nint main(int argc, char **argv) { return 0; }\n')
        ofile.close()
        pc = subprocess.Popen(self.exelist + extra_flags + [source_name, '-o', binary_name])
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('ObjC compiler %s can not compile programs.' % self.name_string())
        if self.is_cross:
            # Can't check if the binaries run so we have to assume they do
            return
        pe = subprocess.Popen(binary_name)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by ObjC compiler %s are not runnable.' % self.name_string())

class ObjCPPCompiler(CPPCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrap):
        CPPCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.language = 'objcpp'
        self.default_suffix = 'mm'

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix == 'mm' or suffix == 'h':
            return True
        return False

    def sanity_check(self, work_dir, environment):
        # TODO try to use sanity_check_impl instead of duplicated code
        source_name = os.path.join(work_dir, 'sanitycheckobjcpp.mm')
        binary_name = os.path.join(work_dir, 'sanitycheckobjcpp')
        extra_flags = self.get_cross_extra_flags(environment, compile=True, link=False)
        if self.is_cross:
            extra_flags += self.get_compile_only_args()
        ofile = open(source_name, 'w')
        ofile.write('#import<stdio.h>\nclass MyClass;int main(int argc, char **argv) { return 0; }\n')
        ofile.close()
        pc = subprocess.Popen(self.exelist + extra_flags + [source_name, '-o', binary_name])
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('ObjC++ compiler %s can not compile programs.' % self.name_string())
        if self.is_cross:
            # Can't check if the binaries run so we have to assume they do
            return
        pe = subprocess.Popen(binary_name)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by ObjC++ compiler %s are not runnable.' % self.name_string())

class MonoCompiler(Compiler):
    def __init__(self, exelist, version):
        super().__init__(exelist, version)
        self.language = 'cs'
        self.default_suffix = 'cs'
        self.id = 'mono'
        self.monorunner = 'mono'

    def get_output_args(self, fname):
        return ['-out:' + fname]

    def get_link_args(self, fname):
        return ['-r:' + fname]

    def get_soname_args(self, shlib_name, path, soversion):
        return []

    def get_werror_args(self):
        return ['-warnaserror']

    def split_shlib_to_parts(self, fname):
        return (None, fname)

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return []

    def get_id(self):
        return self.id

    def get_dependency_gen_args(self, outtarget, outfile):
        return []

    def get_language(self):
        return self.language

    def get_default_suffix(self):
        return self.default_suffix

    def get_exelist(self):
        return self.exelist[:]

    def get_linker_exelist(self):
        return self.exelist[:]

    def get_compile_only_args(self):
        return []

    def get_linker_output_args(self, outputname):
        return []

    def get_coverage_args(self):
        return []

    def get_coverage_link_args(self):
        return []

    def get_std_exe_link_args(self):
        return []

    def get_include_args(self, path):
        return []

    def get_std_shared_lib_link_args(self):
        return []

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix == 'cs':
            return True
        return False

    def get_pic_args(self):
        return []

    def name_string(self):
        return ' '.join(self.exelist)

    def get_pch_use_args(self, pch_dir, header):
        return []

    def get_pch_name(self, header_name):
        return ''

    def sanity_check(self, work_dir, environment):
        src = 'sanity.cs'
        obj = 'sanity.exe'
        source_name = os.path.join(work_dir, src)
        ofile = open(source_name, 'w')
        ofile.write('''public class Sanity {
    static public void Main () {
    }
}
''')
        ofile.close()
        pc = subprocess.Popen(self.exelist + [src], cwd=work_dir)
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Mono compiler %s can not compile programs.' % self.name_string())
        cmdlist = [self.monorunner, obj]
        pe = subprocess.Popen(cmdlist, cwd=work_dir)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by Mono compiler %s are not runnable.' % self.name_string())

    def needs_static_linker(self):
        return False

    def get_buildtype_args(self, buildtype):
        return mono_buildtype_args[buildtype]

class JavaCompiler(Compiler):
    def __init__(self, exelist, version):
        super().__init__(exelist, version)
        self.language = 'java'
        self.default_suffix = 'java'
        self.id = 'unknown'
        self.javarunner = 'java'

    def get_soname_args(self, shlib_name, path, soversion):
        return []

    def get_werror_args(self):
        return ['-Werror']

    def split_shlib_to_parts(self, fname):
        return (None, fname)

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return []

    def get_id(self):
        return self.id

    def get_dependency_gen_args(self, outtarget, outfile):
        return []

    def get_language(self):
        return self.language

    def get_default_suffix(self):
        return self.default_suffix

    def get_exelist(self):
        return self.exelist[:]

    def get_linker_exelist(self):
        return self.exelist[:]

    def get_compile_only_args(self):
        return []

    def get_output_args(self, subdir):
        if subdir == '':
            subdir = './'
        return ['-d', subdir, '-s', subdir]

    def get_linker_output_args(self, outputname):
        return []

    def get_coverage_args(self):
        return []

    def get_coverage_link_args(self):
        return []

    def get_std_exe_link_args(self):
        return []

    def get_include_args(self, path):
        return []

    def get_std_shared_lib_link_args(self):
        return []

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix == 'java':
            return True
        return False

    def get_pic_args(self):
        return []

    def name_string(self):
        return ' '.join(self.exelist)

    def get_pch_use_args(self, pch_dir, header):
        return []

    def get_pch_name(self, header_name):
        return ''

    def get_buildtype_args(self, buildtype):
        return java_buildtype_args[buildtype]

    def sanity_check(self, work_dir, environment):
        src = 'SanityCheck.java'
        obj = 'SanityCheck'
        source_name = os.path.join(work_dir, src)
        ofile = open(source_name, 'w')
        ofile.write('''class SanityCheck {
  public static void main(String[] args) {
    int i;
  }
}
''')
        ofile.close()
        pc = subprocess.Popen(self.exelist + [src], cwd=work_dir)
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Java compiler %s can not compile programs.' % self.name_string())
        cmdlist = [self.javarunner, obj]
        pe = subprocess.Popen(cmdlist, cwd=work_dir)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by Java compiler %s are not runnable.' % self.name_string())

    def needs_static_linker(self):
        return False

class ValaCompiler(Compiler):
    def __init__(self, exelist, version):
        super().__init__(exelist, version)
        self.version = version
        self.id = 'unknown'
        self.language = 'vala'
        self.is_cross = False

    def name_string(self):
        return ' '.join(self.exelist)

    def needs_static_linker(self):
        return False # Because compiles into C.

    def get_exelist(self):
        return self.exelist

    def get_werror_args(self):
        return ['--fatal-warnings']

    def get_language(self):
        return self.language

    def sanity_check(self, work_dir, environment):
        src = 'valatest.vala'
        source_name = os.path.join(work_dir, src)
        ofile = open(source_name, 'w')
        ofile.write('''class SanityCheck : Object {
}
''')
        ofile.close()
        extra_flags = self.get_cross_extra_flags(environment, compile=True, link=False)
        pc = subprocess.Popen(self.exelist + extra_flags + ['-C', '-c', src], cwd=work_dir)
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Vala compiler %s can not compile programs.' % self.name_string())

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        return suffix in ('vala', 'vapi')

    def get_buildtype_args(self, buildtype):
        if buildtype == 'debug' or buildtype == 'debugoptimized':
            return ['--debug']
        return []

class RustCompiler(Compiler):
    def __init__(self, exelist, version):
        super().__init__(exelist, version)
        self.id = 'unknown'
        self.language = 'rust'

    def needs_static_linker(self):
        return False

    def name_string(self):
        return ' '.join(self.exelist)

    def get_exelist(self):
        return self.exelist

    def get_id(self):
        return self.id

    def get_language(self):
        return self.language

    def sanity_check(self, work_dir, environment):
        source_name = os.path.join(work_dir, 'sanity.rs')
        output_name = os.path.join(work_dir, 'rusttest')
        ofile = open(source_name, 'w')
        ofile.write('''fn main() {
}
''')
        ofile.close()
        pc = subprocess.Popen(self.exelist + ['-o', output_name, source_name], cwd=work_dir)
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Rust compiler %s can not compile programs.' % self.name_string())
        if subprocess.call(output_name) != 0:
            raise EnvironmentException('Executables created by Rust compiler %s are not runnable.' % self.name_string())

    def can_compile(self, fname):
        return fname.endswith('.rs')

    def get_dependency_gen_args(self, outfile):
        return ['--dep-info', outfile]

    def get_buildtype_args(self, buildtype):
        return rust_buildtype_args[buildtype]

class SwiftCompiler(Compiler):
    def __init__(self, exelist, version):
        super().__init__(exelist, version)
        self.version = version
        self.id = 'llvm'
        self.language = 'swift'
        self.is_cross = False

    def get_id(self):
        return self.id

    def get_linker_exelist(self):
        return self.exelist

    def name_string(self):
        return ' '.join(self.exelist)

    def needs_static_linker(self):
        return True

    def get_exelist(self):
        return self.exelist

    def get_werror_args(self):
        return ['--fatal-warnings']

    def get_language(self):
        return self.language

    def get_dependency_gen_args(self, outtarget, outfile):
        return ['-emit-dependencies']

    def depfile_for_object(self, objfile):
        return os.path.splitext(objfile)[0] + '.' + self.get_depfile_suffix()

    def get_depfile_suffix(self):
        return 'd'

    def get_output_args(self, target):
        return ['-o', target]

    def get_linker_output_args(self, target):
        return ['-o', target]

    def get_header_import_args(self, headername):
        return ['-import-objc-header', headername]

    def get_warn_args(self, level):
        return []

    def get_buildtype_args(self, buildtype):
        return swift_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return []

    def get_std_exe_link_args(self):
        return ['-emit-executable']

    def get_module_args(self, modname):
        return ['-module-name', modname]

    def get_mod_gen_args(self):
        return ['-emit-module']

    def build_rpath_args(self, *args):
        return [] # FIXME

    def get_include_args(self, dirname):
        return ['-I' + dirname]

    def get_compile_only_args(self):
        return ['-c']

    def sanity_check(self, work_dir, environment):
        src = 'swifttest.swift'
        source_name = os.path.join(work_dir, src)
        output_name = os.path.join(work_dir, 'swifttest')
        ofile = open(source_name, 'w')
        ofile.write('''1 + 2
''')
        ofile.close()
        extra_flags = self.get_cross_extra_flags(environment, compile=True, link=True)
        pc = subprocess.Popen(self.exelist + extra_flags + ['-emit-executable', '-o', output_name, src], cwd=work_dir)
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Swift compiler %s can not compile programs.' % self.name_string())
        if subprocess.call(output_name) != 0:
            raise EnvironmentException('Executables created by Swift compiler %s are not runnable.' % self.name_string())

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        return suffix in ('swift')

class VisualStudioCCompiler(CCompiler):
    std_warn_args = ['/W3']
    std_opt_args= ['/O2']
    vs2010_always_args = ['/nologo', '/showIncludes']
    vs2013_always_args = ['/nologo', '/showIncludes', '/FS']

    def __init__(self, exelist, version, is_cross, exe_wrap):
        CCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.id = 'msvc'
        if int(version.split('.')[0]) > 17:
            self.always_args = VisualStudioCCompiler.vs2013_always_args
        else:
            self.always_args = VisualStudioCCompiler.vs2010_always_args
        self.warn_args = {'1': ['/W2'],
                          '2': ['/W3'],
                          '3': ['/w4']}
        self.base_options = ['b_pch'] # FIXME add lto, pgo and the like

    def get_always_args(self):
        return self.always_args

    def get_buildtype_args(self, buildtype):
        return msvc_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return msvc_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'pch'

    def get_pch_name(self, header):
        chopped = os.path.split(header)[-1].split('.')[:-1]
        chopped.append(self.get_pch_suffix())
        pchname = '.'.join(chopped)
        return pchname

    def get_pch_use_args(self, pch_dir, header):
        base = os.path.split(header)[-1]
        pchname = self.get_pch_name(header)
        return ['/FI' + base, '/Yu' + base, '/Fp' + os.path.join(pch_dir, pchname)]

    def get_compile_only_args(self):
        return ['/c']

    def get_no_optimization_args(self):
        return ['/Od']

    def get_output_args(self, target):
        if target.endswith('.exe'):
            return ['/Fe' + target]
        return ['/Fo' + target]

    def get_dependency_gen_args(self, outtarget, outfile):
        return []

    def get_linker_exelist(self):
        return ['link'] # FIXME, should have same path as compiler.

    def get_linker_always_args(self):
        return ['/nologo']

    def get_linker_output_args(self, outputname):
        return ['/OUT:' + outputname]

    def get_linker_search_args(self, dirname):
        return ['/LIBPATH:' + dirname]

    def get_pic_args(self):
        return [] # PIC is handled by the loader on Windows

    def get_std_shared_lib_link_args(self):
        return ['/DLL']

    def gen_vs_module_defs_args(self, defsfile):
        if not isinstance(defsfile, str):
            raise RuntimeError('Module definitions file should be str')
        # With MSVC, DLLs only export symbols that are explicitly exported,
        # so if a module defs file is specified, we use that to export symbols
        return ['/DEF:' + defsfile]

    def gen_pch_args(self, header, source, pchname):
        objname = os.path.splitext(pchname)[0] + '.obj'
        return (objname, ['/Yc' + header, '/Fp' + pchname, '/Fo' + objname ])

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return []

    # FIXME, no idea what these should be.
    def thread_flags(self):
        return []

    def thread_link_flags(self):
        return []

    def get_options(self):
        return {'c_winlibs' : coredata.UserStringArrayOption('c_winlibs',
                                                             'Windows libs to link against.',
                                                             msvc_winlibs)
                }

    def get_option_link_args(self, options):
        return options['c_winlibs'].value[:]

    def unix_link_flags_to_native(self, args):
        result = []
        for i in args:
            if i.startswith('-L'):
                i = '/LIBPATH:' + i[2:]
            # Translate GNU-style -lfoo library name to the import library
            elif i.startswith('-l'):
                name = i[2:]
                if name in ('m', 'c'):
                    # With MSVC, these are provided by the C runtime which is
                    # linked in by default
                    continue
                else:
                    i = name + '.lib'
            result.append(i)
        return result

    def unix_compile_flags_to_native(self, args):
        result = []
        for i in args:
            # -mms-bitfields is specific to MinGW-GCC
            if i == '-mms-bitfields':
                continue
            result.append(i)
        return result

    def get_include_args(self, path, is_system):
        if path == '':
            path = '.'
        # msvc does not have a concept of system header dirs.
        return ['-I' + path]

    # Visual Studio is special. It ignores arguments it does not
    # understand and you can't tell it to error out on those.
    # http://stackoverflow.com/questions/15259720/how-can-i-make-the-microsoft-c-compiler-treat-unknown-flags-as-errors-rather-t
    def has_argument(self, arg, env):
        warning_text = b'9002'
        code = 'int i;\n'
        (fd, srcname) = tempfile.mkstemp(suffix='.'+self.default_suffix)
        os.close(fd)
        ofile = open(srcname, 'w')
        ofile.write(code)
        ofile.close()
        # Read c_args/cpp_args/etc from the cross-info file (if needed)
        extra_args = self.get_cross_extra_flags(env, compile=True, link=False)
        extra_args += self.get_compile_only_args()
        commands = self.exelist + [arg] + extra_args + [srcname]
        mlog.debug('Running VS compile:')
        mlog.debug('Command line: ', ' '.join(commands))
        mlog.debug('Code:\n', code)
        p = subprocess.Popen(commands, cwd=os.path.split(srcname)[0], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        (stde, stdo) = p.communicate()
        if p.returncode != 0:
            raise MesonException('Compiling test app failed.')
        return not(warning_text in stde or warning_text in stdo)

class VisualStudioCPPCompiler(VisualStudioCCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrap):
        VisualStudioCCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.language = 'cpp'
        self.default_suffix = 'cpp'
        self.base_options = ['b_pch'] # FIXME add lto, pgo and the like

    def can_compile(self, filename):
        suffix = filename.split('.')[-1]
        if suffix in cpp_suffixes:
            return True
        return False

    def get_options(self):
        return {'cpp_eh' : coredata.UserComboOption('cpp_eh',
                                                    'C++ exception handling type.',
                                                    ['none', 'a', 's', 'sc'],
                                                    'sc'),
                'cpp_winlibs' : coredata.UserStringArrayOption('cpp_winlibs',
                                                               'Windows libs to link against.',
                                                               msvc_winlibs)
                }

    def get_option_compile_args(self, options):
        args = []
        std = options['cpp_eh']
        if std.value != 'none':
            args.append('/EH' + std.value)
        return args

    def get_option_link_args(self, options):
        return options['cpp_winlibs'].value[:]

GCC_STANDARD = 0
GCC_OSX = 1
GCC_MINGW = 2

CLANG_STANDARD = 0
CLANG_OSX = 1
CLANG_WIN = 2
# Possibly clang-cl?

def get_gcc_soname_args(gcc_type, shlib_name, path, soversion):
    if soversion is None:
        sostr = ''
    else:
        sostr = '.' + soversion
    if gcc_type == GCC_STANDARD or gcc_type == GCC_MINGW:
        # Might not be correct for mingw but seems to work.
        return ['-Wl,-soname,lib%s.so%s' % (shlib_name, sostr)]
    elif gcc_type == GCC_OSX:
        return ['-install_name', os.path.join(path, 'lib' + shlib_name + '.dylib')]
    else:
        raise RuntimeError('Not implemented yet.')


class GnuCCompiler(CCompiler):
    def __init__(self, exelist, version, gcc_type, is_cross, exe_wrapper=None):
        CCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
        self.id = 'gcc'
        self.gcc_type = gcc_type
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch'],
                          '3' : ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch']}
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.gcc_type != GCC_OSX:
            self.base_options.append('b_lundef')

    def get_pic_args(self):
        if self.gcc_type == GCC_MINGW:
            return [] # On Window gcc defaults to fpic being always on.
        return ['-fPIC']

    def get_always_args(self):
        return ['-pipe']

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'gch'

    def split_shlib_to_parts(self, fname):
        return (os.path.split(fname)[0], fname)

    def get_soname_args(self, shlib_name, path, soversion):
        return get_gcc_soname_args(self.gcc_type, shlib_name, path, soversion)

    def can_compile(self, filename):
        return super().can_compile(filename) or filename.split('.')[-1].lower() == 's' # Gcc can do asm, too.

    def get_options(self):
        opts = {'c_std' : coredata.UserComboOption('c_std', 'C language standard to use',
                                                   ['none', 'c89', 'c99', 'c11', 'gnu89', 'gnu99', 'gnu11'],
                                                   'none')}
        if self.gcc_type == GCC_MINGW:
            opts.update({
                'c_winlibs': coredata.UserStringArrayOption('c_winlibs', 'Standard Win libraries to link against',
                                                            gnu_winlibs),
                })
        return opts

    def get_option_compile_args(self, options):
        args = []
        std = options['c_std']
        if std.value != 'none':
            args.append('-std=' + std.value)
        return args

    def get_option_link_args(self, options):
        if self.gcc_type == GCC_MINGW:
            return options['c_winlibs'].value
        return []

class GnuObjCCompiler(ObjCCompiler):
    std_opt_args = ['-O2']

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        ObjCCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
        self.id = 'gcc'
        # Not really correct, but GNU objc is only used on non-OSX non-win. File a bug
        # if this breaks your use case.
        self.gcc_type = GCC_STANDARD
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch'],
                          '3' : ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch']}
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.gcc_type != GCC_OSX:
            self.base_options.append('b_lundef')

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'gch'

    def get_soname_args(self, shlib_name, path, soversion):
        return get_gcc_soname_args(self.gcc_type, shlib_name, path, soversion)

class GnuObjCPPCompiler(ObjCPPCompiler):
    std_opt_args = ['-O2']

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        ObjCCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
        self.id = 'gcc'
        # Not really correct, but GNU objc is only used on non-OSX non-win. File a bug
        # if this breaks your use case.
        self.gcc_type = GCC_STANDARD
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '3' : ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor']}
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.gcc_type != GCC_OSX:
            self.base_options.append('b_lundef')

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'gch'

    def get_soname_args(self, shlib_name, path, soversion):
        return get_gcc_soname_args(self.gcc_type, shlib_name, path, soversion)

class ClangObjCCompiler(GnuObjCCompiler):
    def __init__(self, exelist, version, cltype, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper)
        self.id = 'clang'
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        self.clang_type = cltype
        if self.clang_type != CLANG_OSX:
            self.base_options.append('b_lundef')

class ClangObjCPPCompiler(GnuObjCPPCompiler):
    def __init__(self, exelist, version, cltype, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper)
        self.id = 'clang'
        self.clang_type = cltype
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.clang_type != CLANG_OSX:
            self.base_options.append('b_lundef')

class ClangCCompiler(CCompiler):
    def __init__(self, exelist, version, clang_type, is_cross, exe_wrapper=None):
        CCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
        self.id = 'clang'
        self.clang_type = clang_type
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch'],
                          '3' : ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch']}
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.clang_type != CLANG_OSX:
            self.base_options.append('b_lundef')

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'pch'

    def can_compile(self, filename):
        return super().can_compile(filename) or filename.split('.')[-1].lower() == 's' # Clang can do asm, too.

    def get_pch_use_args(self, pch_dir, header):
        # Workaround for Clang bug http://llvm.org/bugs/show_bug.cgi?id=15136
        # This flag is internal to Clang (or at least not documented on the man page)
        # so it might change semantics at any time.
        return ['-include-pch', os.path.join (pch_dir, self.get_pch_name (header))]

    def get_options(self):
        return {'c_std' : coredata.UserComboOption('c_std', 'C language standard to use',
                                                   ['none', 'c89', 'c99', 'c11'],
                                                   'none')}

    def get_option_compile_args(self, options):
        args = []
        std = options['c_std']
        if std.value != 'none':
            args.append('-std=' + std.value)
        return args

    def get_option_link_args(self, options):
        return []

class GnuCPPCompiler(CPPCompiler):
    # may need to separate the latter to extra_debug_args or something
    std_debug_args = ['-g']

    def __init__(self, exelist, version, gcc_type, is_cross, exe_wrap):
        CPPCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
        self.id = 'gcc'
        self.gcc_type = gcc_type
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '3': ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor']}
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.gcc_type != GCC_OSX:
            self.base_options.append('b_lundef')

    def get_always_args(self):
        return ['-pipe']

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'gch'

    def get_soname_args(self, shlib_name, path, soversion):
        return get_gcc_soname_args(self.gcc_type, shlib_name, path, soversion)

    def get_options(self):
        opts = {'cpp_std' : coredata.UserComboOption('cpp_std', 'C++ language standard to use',
                                                     ['none', 'c++03', 'c++11', 'c++14', 'c++1z'],
                                                     'none'),
                'cpp_debugstl': coredata.UserBooleanOption('cpp_debugstl',
                                                           'STL debug mode',
                                                           False)}
        if self.gcc_type == GCC_MINGW:
            opts.update({
                'cpp_winlibs': coredata.UserStringArrayOption('c_winlibs', 'Standard Win libraries to link against',
                                                              gnu_winlibs),
                })
        return opts

    def get_option_compile_args(self, options):
        args = []
        std = options['cpp_std']
        if std.value != 'none':
            args.append('-std=' + std.value)
        if options['cpp_debugstl'].value:
            args.append('-D_GLIBCXX_DEBUG=1')
        return args

    def get_option_link_args(self, options):
        if self.gcc_type == GCC_MINGW:
            return options['cpp_winlibs'].value
        return []

class ClangCPPCompiler(CPPCompiler):
    def __init__(self, exelist, version, cltype, is_cross, exe_wrapper=None):
        CPPCompiler.__init__(self, exelist, version, is_cross, exe_wrapper)
        self.id = 'clang'
        self.warn_args = {'1': ['-Wall', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '2': ['-Wall', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor'],
                          '3': ['-Wall', '-Wpedantic', '-Wextra', '-Winvalid-pch', '-Wnon-virtual-dtor']}
        self.clang_type = cltype
        self.base_options = ['b_pch', 'b_lto', 'b_pgo', 'b_sanitize', 'b_coverage']
        if self.clang_type != CLANG_OSX:
            self.base_options.append('b_lundef')

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def get_pch_suffix(self):
        return 'pch'

    def get_pch_use_args(self, pch_dir, header):
        # Workaround for Clang bug http://llvm.org/bugs/show_bug.cgi?id=15136
        # This flag is internal to Clang (or at least not documented on the man page)
        # so it might change semantics at any time.
        return ['-include-pch', os.path.join (pch_dir, self.get_pch_name (header))]

    def get_options(self):
        return {'cpp_std' : coredata.UserComboOption('cpp_std', 'C++ language standard to use',
                                                   ['none', 'c++03', 'c++11', 'c++14', 'c++1z'],
                                                   'none')}

    def get_option_compile_args(self, options):
        args = []
        std = options['cpp_std']
        if std.value != 'none':
            args.append('-std=' + std.value)
        return args

    def get_option_link_args(self, options):
        return []

class FortranCompiler(Compiler):
    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version)
        self.is_cross = is_cross
        self.exe_wrapper = exe_wrapper
        self.language = 'fortran'
        # Not really correct but I don't have Fortran compilers to test with. Sorry.
        self.gcc_type = GCC_STANDARD
        self.id = "IMPLEMENTATION CLASSES MUST SET THIS"

    def get_id(self):
        return self.id

    def name_string(self):
        return ' '.join(self.exelist)

    def get_exelist(self):
        return self.exelist

    def get_language(self):
        return self.language

    def get_pic_args(self):
        if self.gcc_type == GCC_MINGW:
            return [] # On Windows gcc defaults to fpic being always on.
        return ['-fPIC']

    def get_std_shared_lib_link_args(self):
        return ['-shared']

    def needs_static_linker(self):
        return True

    def sanity_check(self, work_dir, environment):
        source_name = os.path.join(work_dir, 'sanitycheckf.f90')
        binary_name = os.path.join(work_dir, 'sanitycheckf')
        ofile = open(source_name, 'w')
        ofile.write('''program prog
     print *, "Fortran compilation is working."
end program prog
''')
        ofile.close()
        extra_flags = self.get_cross_extra_flags(environment, compile=True, link=True)
        pc = subprocess.Popen(self.exelist + extra_flags + [source_name, '-o', binary_name])
        pc.wait()
        if pc.returncode != 0:
            raise EnvironmentException('Compiler %s can not compile programs.' % self.name_string())
        if self.is_cross:
            if self.exe_wrapper is None:
                # Can't check if the binaries run so we have to assume they do
                return
            cmdlist = self.exe_wrapper + [binary_name]
        else:
            cmdlist = [binary_name]
        pe = subprocess.Popen(cmdlist, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
        pe.wait()
        if pe.returncode != 0:
            raise EnvironmentException('Executables created by Fortran compiler %s are not runnable.' % self.name_string())

    def get_std_warn_args(self, level):
        return FortranCompiler.std_warn_args

    def get_buildtype_args(self, buildtype):
        return gnulike_buildtype_args[buildtype]

    def get_buildtype_linker_args(self, buildtype):
        return gnulike_buildtype_linker_args[buildtype]

    def split_shlib_to_parts(self, fname):
        return (os.path.split(fname)[0], fname)

    def get_soname_args(self, shlib_name, path, soversion):
        return get_gcc_soname_args(self.gcc_type, shlib_name, path, soversion)

    def get_dependency_gen_args(self, outtarget, outfile):
        # Disabled until this is fixed:
        # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62162
        #return ['-cpp', '-MMD', '-MQ', outtarget]
        return []

    def get_output_args(self, target):
        return ['-o', target]

    def get_compile_only_args(self):
        return ['-c']

    def get_linker_exelist(self):
        return self.exelist[:]

    def get_linker_output_args(self, outputname):
        return ['-o', outputname]

    def can_compile(self, src):
        if hasattr(src, 'fname'):
            src = src.fname
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f95' or suffix == '.f90':
            return True
        return False

    def get_include_args(self, path, is_system):
        return ['-I' + path]

    def get_module_outdir_args(self, path):
        return ['-J' + path]

    def depfile_for_object(self, objfile):
        return objfile + '.' + self.get_depfile_suffix()

    def get_depfile_suffix(self):
        return 'd'

    def get_std_exe_link_args(self):
        return []

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return build_unix_rpath_args(build_dir, rpath_paths, install_rpath)

    def module_name_to_filename(self, module_name):
        return module_name.lower() + '.mod'

    def get_warn_args(self, level):
        return ['-Wall']


class GnuFortranCompiler(FortranCompiler):
    def __init__(self, exelist, version, gcc_type, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.gcc_type = gcc_type
        self.id = 'gcc'

    def get_always_args(self):
        return ['-pipe']

class G95FortranCompiler(FortranCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'g95'

    def get_module_outdir_args(self, path):
        return ['-fmod='+path]

    def get_always_args(self):
        return ['-pipe']

class SunFortranCompiler(FortranCompiler):
    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'sun'

    def get_dependency_gen_args(self, outtarget, outfile):
        return ['-fpp']

    def get_always_args(self):
        return []

    def get_warn_args(self):
        return []

    def get_module_outdir_args(self, path):
        return ['-moddir='+path]

class IntelFortranCompiler(FortranCompiler):
    std_warn_args = ['-warn', 'all']
    
    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'intel'
        
    def get_module_outdir_args(self, path):
        return ['-module', path]

    def can_compile(self, src):
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f90':
            return True
        return False

    def get_warn_args(self, level):
        return IntelFortranCompiler.std_warn_args

class PathScaleFortranCompiler(FortranCompiler):
    std_warn_args = ['-fullwarn']

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'pathscale'

    def get_module_outdir_args(self, path):
        return ['-module', path]

    def can_compile(self, src):
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f90' or suffix == '.f95':
            return True
        return False

    def get_std_warn_args(self, level):
        return PathScaleFortranCompiler.std_warn_args

class PGIFortranCompiler(FortranCompiler):
    std_warn_args = ['-Minform=inform']

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'pgi'

    def get_module_outdir_args(self, path):
        return ['-module', path]

    def can_compile(self, src):
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f90' or suffix == '.f95':
            return True
        return False

    def get_warn_args(self, level):
        return PGIFortranCompiler.std_warn_args


class Open64FortranCompiler(FortranCompiler):
    std_warn_args = ['-fullwarn']

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'open64'

    def get_module_outdir_args(self, path):
        return ['-module', path]

    def can_compile(self, src):
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f90' or suffix == '.f95':
            return True
        return False

    def get_warn_args(self, level):
        return Open64FortranCompiler.std_warn_args

class NAGFortranCompiler(FortranCompiler):
    std_warn_args = []

    def __init__(self, exelist, version, is_cross, exe_wrapper=None):
        super().__init__(exelist, version, is_cross, exe_wrapper=None)
        self.id = 'nagfor'

    def get_module_outdir_args(self, path):
        return ['-mdir', path]

    def get_always_args(self):
        return []

    def can_compile(self, src):
        suffix = os.path.splitext(src)[1].lower()
        if suffix == '.f' or suffix == '.f90' or suffix == '.f95':
            return True
        return False

    def get_warn_args(self, level):
        return NAGFortranCompiler.std_warn_args


class VisualStudioLinker():
    always_args = ['/NOLOGO']
    def __init__(self, exelist):
        self.exelist = exelist

    def get_exelist(self):
        return self.exelist

    def get_std_link_args(self):
        return []

    def get_buildtype_linker_args(self, buildtype):
        return []

    def get_output_args(self, target):
        return ['/OUT:' + target]

    def get_coverage_link_args(self):
        return []

    def get_always_args(self):
        return VisualStudioLinker.always_args

    def get_linker_always_args(self):
        return VisualStudioLinker.always_args

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return []

    def thread_link_flags(self):
        return []

    def get_option_link_args(self, options):
        return []

    def unix_link_flags_to_native(self, args):
        return args[:]

    def unix_compile_flags_to_native(self, args):
        return args[:]

class ArLinker():

    def __init__(self, exelist):
        self.exelist = exelist
        self.id = 'ar'
        pc = subprocess.Popen(self.exelist + ['-h'], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
        (stdo, _) = pc.communicate()
        # Enable deterministic builds if they are available.
        if b'[D]' in stdo:
            self.std_args = ['csrD']
        else:
            self.std_args = ['csr']

    def build_rpath_args(self, build_dir, rpath_paths, install_rpath):
        return []

    def get_exelist(self):
        return self.exelist

    def get_std_link_args(self):
        return self.std_args

    def get_output_args(self, target):
        return [target]

    def get_buildtype_linker_args(self, buildtype):
        return []

    def get_linker_always_args(self):
        return []

    def get_coverage_link_args(self):
        return []

    def get_always_args(self):
        return []

    def thread_link_flags(self):
        return []

    def get_option_link_args(self, options):
        return []

    def unix_link_flags_to_native(self, args):
        return args[:]

    def unix_compile_flags_to_native(self, args):
        return args[:]