files: # Copyright 2012-2016 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 os, re, subprocess, platform
  from . import coredata
  from . import mesonlib
  from . import mlog
  from .compilers import *
  from .mesonlib import EnvironmentException, Popen_safe
  import configparser
  import shlex
  import shutil
  
  build_filename = 'meson.build'
  
  def find_coverage_tools():
      gcovr_exe = 'gcovr'
      lcov_exe = 'lcov'
      genhtml_exe = 'genhtml'
  
      if not mesonlib.exe_exists([gcovr_exe, '--version']):
          gcovr_exe = None
      if not mesonlib.exe_exists([lcov_exe, '--version']):
          lcov_exe = None
      if not mesonlib.exe_exists([genhtml_exe, '--version']):
          genhtml_exe = None
      return gcovr_exe, lcov_exe, genhtml_exe
  
  def detect_ninja(version='1.5'):
      for n in ['ninja', 'ninja-build']:
          try:
              p, found = Popen_safe([n, '--version'])[0:2]
          except (FileNotFoundError, PermissionError):
              # Doesn't exist in PATH or isn't executable
              continue
          # Perhaps we should add a way for the caller to know the failure mode
          # (not found or too old)
          if p.returncode == 0 and mesonlib.version_compare(found, '>=' + version):
              return n
  
  def detect_native_windows_arch():
      """
      The architecture of Windows itself: x86 or amd64
      """
      # These env variables are always available. See:
      # https://msdn.microsoft.com/en-us/library/aa384274(VS.85).aspx
      # https://blogs.msdn.microsoft.com/david.wang/2006/03/27/howto-detect-process-bitness/
      arch = os.environ.get('PROCESSOR_ARCHITEW6432', '').lower()
      if not arch:
          try:
              # If this doesn't exist, something is messing with the environment
              arch = os.environ['PROCESSOR_ARCHITECTURE'].lower()
          except KeyError:
              raise EnvironmentException('Unable to detect native OS architecture')
      return arch
  
  def detect_windows_arch(compilers):
      """
      Detecting the 'native' architecture of Windows is not a trivial task. We
      cannot trust that the architecture that Python is built for is the 'native'
      one because you can run 32-bit apps on 64-bit Windows using WOW64 and
      people sometimes install 32-bit Python on 64-bit Windows.
  
      We also can't rely on the architecture of the OS itself, since it's
      perfectly normal to compile and run 32-bit applications on Windows as if
      they were native applications. It's a terrible experience to require the
      user to supply a cross-info file to compile 32-bit applications on 64-bit
      Windows. Thankfully, the only way to compile things with Visual Studio on
      Windows is by entering the 'msvc toolchain' environment, which can be
      easily detected.
  
      In the end, the sanest method is as follows:
      1. Check if we're in an MSVC toolchain environment, and if so, return the
         MSVC toolchain architecture as our 'native' architecture.
      2. If not, check environment variables that are set by Windows and WOW64 to
         find out the architecture that Windows is built for, and use that as our
         'native' architecture.
      """
      os_arch = detect_native_windows_arch()
      if os_arch != 'amd64':
          return os_arch
      # If we're on 64-bit Windows, 32-bit apps can be compiled without
      # cross-compilation. So if we're doing that, just set the native arch as
      # 32-bit and pretend like we're running under WOW64. Else, return the
      # actual Windows architecture that we deduced above.
      for compiler in compilers.values():
          # Check if we're using and inside an MSVC toolchain environment
          if compiler.id == 'msvc' and 'VCINSTALLDIR' in os.environ:
              # 'Platform' is only set when the target arch is not 'x86'.
              # It's 'x64' when targetting x86_64 and 'arm' when targetting ARM.
              platform = os.environ.get('Platform', 'x86').lower()
              if platform == 'x86':
                  return platform
          if compiler.id == 'gcc' and compiler.has_define('__i386__'):
              return 'x86'
      return os_arch
  
  def detect_cpu_family(compilers):
      """
      Python is inconsistent in its platform module.
      It returns different values for the same cpu.
      For x86 it might return 'x86', 'i686' or somesuch.
      Do some canonicalization.
      """
      if mesonlib.is_windows():
          trial = detect_windows_arch(compilers)
      else:
          trial = platform.machine().lower()
      if trial.startswith('i') and trial.endswith('86'):
          return 'x86'
      if trial.startswith('arm'):
          return 'arm'
      if trial in ('amd64', 'x64'):
          trial = 'x86_64'
      if trial == 'x86_64':
          # On Linux (and maybe others) there can be any mixture of 32/64 bit
          # code in the kernel, Python, system etc. The only reliable way
          # to know is to check the compiler defines.
          for c in compilers.values():
              try:
                  if c.has_define('__i386__'):
                      return 'x86'
              except mesonlib.MesonException:
                  # Ignore compilers that do not support has_define.
                  pass
          return 'x86_64'
      # Add fixes here as bugs are reported.
      return trial
  
  def detect_cpu(compilers):
      if mesonlib.is_windows():
          trial = detect_windows_arch(compilers)
      else:
          trial = platform.machine().lower()
      if trial in ('amd64', 'x64'):
          trial = 'x86_64'
      if trial == 'x86_64':
          # Same check as above for cpu_family
          for c in compilers.values():
              try:
                  if c.has_define('__i386__'):
                      return 'i686' # All 64 bit cpus have at least this level of x86 support.
              except mesonlib.MesonException:
                  pass
          return 'x86_64'
      # Add fixes here as bugs are reported.
      return trial
  
  def detect_system():
      return platform.system().lower()
  
  
  def for_windows(is_cross, env):
      """
      Host machine is windows?
  
      Note: 'host' is the machine on which compiled binaries will run
      """
      if not is_cross:
          return mesonlib.is_windows()
      elif env.cross_info.has_host():
          return env.cross_info.config['host_machine']['system'] == 'windows'
      return False
  
  def for_darwin(is_cross, env):
      """
      Host machine is Darwin (iOS/OS X)?
  
      Note: 'host' is the machine on which compiled binaries will run
      """
      if not is_cross:
          return mesonlib.is_osx()
      elif env.cross_info.has_host():
          return env.cross_info.config['host_machine']['system'] == 'darwin'
      return False
  
  
  def search_version(text):
      # Usually of the type 4.1.4 but compiler output may contain
      # stuff like this:
      # (Sourcery CodeBench Lite 2014.05-29) 4.8.3 20140320 (prerelease)
      # Limiting major version number to two digits seems to work
      # thus far. When we get to GCC 100, this will break, but
      # if we are still relevant when that happens, it can be
      # considered an achievement in itself.
      #
      # This regex is reaching magic levels. If it ever needs
      # to be updated, do not complexify but convert to something
      # saner instead.
      version_regex = '(?<!(\d|\.))(\d{1,2}(\.\d+)+(-[a-zA-Z0-9]+)?)'
      match = re.search(version_regex, text)
      if match:
          return match.group(0)
      return 'unknown version'
  
  class Environment:
      private_dir = 'meson-private'
      log_dir = 'meson-logs'
      coredata_file = os.path.join(private_dir, 'coredata.dat')
  
      def __init__(self, source_dir, build_dir, main_script_launcher, options, original_cmd_line_args):
          self.source_dir = source_dir
          self.build_dir = build_dir
          self.meson_script_launcher = main_script_launcher
          self.scratch_dir = os.path.join(build_dir, Environment.private_dir)
          self.log_dir = os.path.join(build_dir, Environment.log_dir)
          os.makedirs(self.scratch_dir, exist_ok=True)
          os.makedirs(self.log_dir, exist_ok=True)
          try:
              cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
              self.coredata = coredata.load(cdf)
              self.first_invocation = False
          except FileNotFoundError:
              # WARNING: Don't use any values from coredata in __init__. It gets
              # re-initialized with project options by the interpreter during
              # build file parsing.
              self.coredata = coredata.CoreData(options)
              self.coredata.meson_script_launcher = self.meson_script_launcher
              self.first_invocation = True
          if self.coredata.cross_file:
              self.cross_info = CrossBuildInfo(self.coredata.cross_file)
          else:
              self.cross_info = None
          self.cmd_line_options = options
          self.original_cmd_line_args = original_cmd_line_args
  
          # List of potential compilers.
          if mesonlib.is_windows():
              self.default_c = ['cl', 'cc', 'gcc', 'clang']
              self.default_cpp = ['cl', 'c++', 'g++', 'clang++']
          else:
              self.default_c = ['cc']
              self.default_cpp = ['c++']
          self.default_objc = ['cc']
          self.default_objcpp = ['c++']
          self.default_fortran = ['gfortran', 'g95', 'f95', 'f90', 'f77']
          self.default_static_linker = 'ar'
          self.vs_static_linker = 'lib'
  
          # Various prefixes and suffixes for import libraries, shared libraries,
          # static libraries, and executables.
          # Versioning is added to these names in the backends as-needed.
          cross = self.is_cross_build()
          if (not cross and mesonlib.is_windows()) \
                  or (cross and self.cross_info.has_host() and self.cross_info.config['host_machine']['system'] == 'windows'):
              self.exe_suffix = 'exe'
              self.object_suffix = 'obj'
              self.win_libdir_layout = True
          else:
              self.exe_suffix = ''
              self.object_suffix = 'o'
              self.win_libdir_layout = False
  
      def is_cross_build(self):
          return self.cross_info is not None
  
      def dump_coredata(self, mtime):
          cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
          coredata.save(self.coredata, cdf)
          os.utime(cdf, times=(mtime, mtime))
  
      def get_script_dir(self):
          import mesonbuild.scripts
          return os.path.dirname(mesonbuild.scripts.__file__)
  
      def get_log_dir(self):
          return self.log_dir
  
      def get_coredata(self):
          return self.coredata
  
      def get_build_command(self):
          return self.meson_script_launcher
  
      def is_header(self, fname):
          return is_header(fname)
  
      def is_source(self, fname):
          return is_source(fname)
  
      def is_assembly(self, fname):
          return is_assembly(fname)
  
      def is_llvm_ir(self, fname):
          return is_llvm_ir(fname)
  
      def is_object(self, fname):
          return is_object(fname)
  
      def is_library(self, fname):
          return is_library(fname)
  
      def had_argument_for(self, option):
          trial1 = '--' + option
          trial2 = '-D' + option
          previous_is_plaind = False
          for i in self.original_cmd_line_args:
              if i.startswith(trial1) or i.startswith(trial2):
                  return True
              if previous_is_plaind and i.startswith(option):
                  return True
              previous_is_plaind = i == '-D'
          return False
  
      def merge_options(self, options):
          for (name, value) in options.items():
              if name not in self.coredata.user_options:
                  self.coredata.user_options[name] = value
              else:
                  oldval = self.coredata.user_options[name]
                  if type(oldval) != type(value):
                      self.coredata.user_options[name] = value
  
      @staticmethod
      def get_gnu_compiler_defines(compiler):
          """
          Detect GNU compiler platform type (Apple, MinGW, Unix)
          """
          # Arguments to output compiler pre-processor defines to stdout
          # gcc, g++, and gfortran all support these arguments
          args = compiler + ['-E', '-dM', '-']
          p, output = Popen_safe(args, write='', stdin=subprocess.PIPE)[0:2]
          if p.returncode != 0:
              raise EnvironmentException('Unable to detect GNU compiler type:\n' + output)
          # Parse several lines of the type:
          # `#define ___SOME_DEF some_value`
          # and extract `___SOME_DEF`
          defines = {}
          for line in output.split('\n'):
              if not line:
                  continue
              d, *rest = line.split(' ', 2)
              if d != '#define':
                  continue
              if len(rest) == 1:
                  defines[rest] = True
              if len(rest) == 2:
                  defines[rest[0]] = rest[1]
          return defines
  
      @staticmethod
      def get_gnu_version_from_defines(defines):
          dot = '.'
          major = defines.get('__GNUC__', '0')
          minor = defines.get('__GNUC_MINOR__', '0')
          patch = defines.get('__GNUC_PATCHLEVEL__', '0')
          return dot.join((major, minor, patch))
  
      @staticmethod
      def get_gnu_compiler_type(defines):
          # Detect GCC type (Apple, MinGW, Cygwin, Unix)
          if '__APPLE__' in defines:
              return GCC_OSX
          elif '__MINGW32__' in defines or '__MINGW64__' in defines:
              return GCC_MINGW
          # We ignore Cygwin for now, and treat it as a standard GCC
          return GCC_STANDARD
  
      def _get_compilers(self, lang, evar, want_cross):
          '''
          The list of compilers is detected in the exact same way for
          C, C++, ObjC, ObjC++, Fortran so consolidate it here.
          '''
          if self.is_cross_build() and want_cross:
              compilers = [mesonlib.stringlistify(self.cross_info.config['binaries'][lang])]
              ccache = []
              is_cross = True
              if self.cross_info.need_exe_wrapper():
                  exe_wrap = self.cross_info.config['binaries'].get('exe_wrapper', None)
              else:
                  exe_wrap = []
          elif evar in os.environ:
              compilers = [shlex.split(os.environ[evar])]
              ccache = []
              is_cross = False
              exe_wrap = None
          else:
              compilers = getattr(self, 'default_' + lang)
              ccache = self.detect_ccache()
              is_cross = False
              exe_wrap = None
          return compilers, ccache, is_cross, exe_wrap
  
      def _handle_compiler_exceptions(self, exceptions, compilers):
          errmsg = 'Unknown compiler(s): ' + str(compilers)
          if exceptions:
              errmsg += '\nThe follow exceptions were encountered:'
              for (c, e) in exceptions.items():
                  errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
          raise EnvironmentException(errmsg)
  
      def _detect_c_or_cpp_compiler(self, lang, evar, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers(lang, evar, want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  basename = os.path.basename(compiler[-1]).lower()
                  if basename == 'cl' or basename == 'cl.exe':
                      arg = '/?'
                  else:
                      arg = '--version'
                  p, out, err = Popen_safe(compiler + [arg])
              except OSError as e:
                  popen_exceptions[' '.join(compiler + [arg])] = e
                  continue
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  gtype = self.get_gnu_compiler_type(defines)
                  version = self.get_gnu_version_from_defines(defines)
                  cls = GnuCCompiler if lang == 'c' else GnuCPPCompiler
                  return cls(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
              if 'clang' in out:
                  if 'Apple' in out or for_darwin(want_cross, self):
                      cltype = CLANG_OSX
                  else:
                      cltype = CLANG_STANDARD
                  cls = ClangCCompiler if lang == 'c' else ClangCPPCompiler
                  return cls(ccache + compiler, version, cltype, is_cross, exe_wrap)
              if 'Microsoft' in out or 'Microsoft' in err:
                  # Visual Studio prints version number to stderr but
                  # everything else to stdout. Why? Lord only knows.
                  version = search_version(err)
                  cls = VisualStudioCCompiler if lang == 'c' else VisualStudioCPPCompiler
                  return cls(compiler, version, is_cross, exe_wrap)
              if '(ICC)' in out:
                  # TODO: add microsoft add check OSX
                  inteltype = ICC_STANDARD
                  cls = IntelCCompiler if lang == 'c' else IntelCPPCompiler
                  return cls(ccache + compiler, version, inteltype, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_c_compiler(self, want_cross):
          return self._detect_c_or_cpp_compiler('c', 'CC', want_cross)
  
      def detect_cpp_compiler(self, want_cross):
          return self._detect_c_or_cpp_compiler('cpp', 'CXX', want_cross)
  
      def detect_fortran_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('fortran', 'FC', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              for arg in ['--version', '-V']:
                  try:
                      p, out, err = Popen_safe(compiler + [arg])
                  except OSError as e:
                      popen_exceptions[' '.join(compiler + [arg])] = e
                      continue
  
                  version = search_version(out)
  
                  if 'GNU Fortran' in out:
                      defines = self.get_gnu_compiler_defines(compiler)
                      if not defines:
                          popen_exceptions[compiler] = 'no pre-processor defines'
                          continue
                      gtype = self.get_gnu_compiler_type(defines)
                      version = self.get_gnu_version_from_defines(defines)
                      return GnuFortranCompiler(compiler, version, gtype, is_cross, exe_wrap, defines)
  
                  if 'G95' in out:
                      return G95FortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'Sun Fortran' in err:
                      version = search_version(err)
                      return SunFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'ifort (IFORT)' in out:
                      return IntelFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'PathScale EKOPath(tm)' in err:
                      return PathScaleFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'PGI Compilers' in out:
                      return PGIFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'Open64 Compiler Suite' in err:
                      return Open64FortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'NAG Fortran' in err:
                      return NAGFortranCompiler(compiler, version, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def get_scratch_dir(self):
          return self.scratch_dir
  
      def get_depfixer(self):
          path = os.path.split(__file__)[0]
          return os.path.join(path, 'depfixer.py')
  
      def detect_objc_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('objc', 'OBJC', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  p, out, err = Popen_safe(compiler + ['--version'])
              except OSError:
                  popen_exceptions[' '.join(compiler + [arg])] = e
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuObjCCompiler(ccache + compiler, version, is_cross, exe_wrap, defines)
              if out.startswith('Apple LLVM'):
                  return ClangObjCCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
              if out.startswith('clang'):
                  return ClangObjCCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_objcpp_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('objcpp', 'OBJCXX', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  p, out, err = Popen_safe(compiler + ['--version'])
              except OSError:
                  popen_exceptions[' '.join(compiler + [arg])] = e
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuObjCPPCompiler(ccache + compiler, version, is_cross, exe_wrap, defines)
              if out.startswith('Apple LLVM'):
                  return ClangObjCPPCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
              if out.startswith('clang'):
                  return ClangObjCPPCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_java_compiler(self):
          exelist = ['javac']
          try:
              p, out, err = Popen_safe(exelist + ['-version'])
          except OSError:
              raise EnvironmentException('Could not execute Java compiler "%s"' % ' '.join(exelist))
          version = search_version(err)
          if 'javac' in err:
              return JavaCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_cs_compiler(self):
          exelist = ['mcs']
          try:
              p, out, err = Popen_safe(exelist + ['--version'])
          except OSError:
              raise EnvironmentException('Could not execute C# compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'Mono' in out:
              return MonoCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_vala_compiler(self):
          exelist = ['valac']
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute Vala compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'Vala' in out:
              return ValaCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_rust_compiler(self):
          exelist = ['rustc']
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute Rust compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'rustc' in out:
              return RustCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_d_compiler(self, want_cross):
          is_cross = False
          # Search for a D compiler.
          # We prefer LDC over GDC unless overridden with the DC
          # environment variable because LDC has a much more
          # up to date language version at time (2016).
          if 'DC' in os.environ:
              exelist = shlex.split(os.environ['DC'])
          elif self.is_cross_build() and want_cross:
              exelist = mesonlib.stringlistify(self.cross_info.config['binaries']['d'])
              is_cross = True
          elif shutil.which("ldc2"):
              exelist = ['ldc2']
          elif shutil.which("ldc"):
              exelist = ['ldc']
          elif shutil.which("gdc"):
              exelist = ['gdc']
          elif shutil.which("dmd"):
              exelist = ['dmd']
          else:
              raise EnvironmentException('Could not find any supported D compiler.')
  
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute D compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'LLVM D compiler' in out:
              return LLVMDCompiler(exelist, version, is_cross)
          elif 'gdc' in out:
              return GnuDCompiler(exelist, version, is_cross)
          elif 'Digital Mars' in out:
              return DmdDCompiler(exelist, version, is_cross)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_swift_compiler(self):
          exelist = ['swiftc']
          try:
              p, _, err = Popen_safe(exelist + ['-v'])
          except OSError:
              raise EnvironmentException('Could not execute Swift compiler "%s"' % ' '.join(exelist))
          version = search_version(err)
          if 'Swift' in err:
              return SwiftCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_static_linker(self, compiler):
          if compiler.is_cross:
              linker = self.cross_info.config['binaries']['ar']
              if isinstance(linker, str):
                  linker = [linker]
          else:
              evar = 'AR'
              if evar in os.environ:
                  linker = shlex.split(os.environ[evar])
              elif isinstance(compiler, VisualStudioCCompiler):
                  linker = [self.vs_static_linker]
              else:
                  linker = [self.default_static_linker]
          basename = os.path.basename(linker[-1]).lower()
          if basename == 'lib' or basename == 'lib.exe':
              arg = '/?'
          else:
              arg = '--version'
          try:
              p, out, err = Popen_safe(linker + [arg])
          except OSError:
              raise EnvironmentException('Could not execute static linker "%s".' % ' '.join(linker))
          if '/OUT:' in out or '/OUT:' in err:
              return VisualStudioLinker(linker)
          if p.returncode == 0:
              return ArLinker(linker)
          if p.returncode == 1 and err.startswith('usage'): # OSX
              return ArLinker(linker)
          raise EnvironmentException('Unknown static linker "%s"' % ' '.join(linker))
  
      def detect_ccache(self):
          try:
              has_ccache = subprocess.call(['ccache', '--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
          except OSError:
              has_ccache = 1
          if has_ccache == 0:
              cmdlist = ['ccache']
          else:
              cmdlist = []
          return cmdlist
  
      def get_source_dir(self):
          return self.source_dir
  
      def get_build_dir(self):
          return self.build_dir
  
      def get_exe_suffix(self):
          return self.exe_suffix
  
      def get_import_lib_dir(self):
          "Install dir for the import library (library used for linking)"
          return self.get_libdir()
  
      def get_shared_lib_dir(self):
          "Install dir for the shared library"
          if self.win_libdir_layout:
              return self.get_bindir()
          return self.get_libdir()
  
      def get_static_lib_dir(self):
          "Install dir for the static library"
          return self.get_libdir()
  
      def get_object_suffix(self):
          return self.object_suffix
  
      def get_prefix(self):
          return self.coredata.get_builtin_option('prefix')
  
      def get_libdir(self):
          return self.coredata.get_builtin_option('libdir')
  
      def get_libexecdir(self):
          return self.coredata.get_builtin_option('libexecdir')
  
      def get_bindir(self):
          return self.coredata.get_builtin_option('bindir')
  
      def get_includedir(self):
          return self.coredata.get_builtin_option('includedir')
  
      def get_mandir(self):
          return self.coredata.get_builtin_option('mandir')
  
      def get_datadir(self):
          return self.coredata.get_builtin_option('datadir')
  
  
  def get_args_from_envvars(compiler):
      """
      @compiler: Compiler to fetch environment flags for
  
      Returns a tuple of (compile_flags, link_flags) for the specified language
      from the inherited environment
      """
      def log_var(var, val):
          if val:
              mlog.log('Appending {} from environment: {!r}'.format(var, val))
  
      lang = compiler.get_language()
      compiler_is_linker = False
      if hasattr(compiler, 'get_linker_exelist'):
          compiler_is_linker = (compiler.get_exelist() == compiler.get_linker_exelist())
  
      if lang not in ('c', 'cpp', 'objc', 'objcpp', 'fortran', 'd'):
          return [], []
  
      # Compile flags
      cflags_mapping = {'c': 'CFLAGS',
                        'cpp': 'CXXFLAGS',
                        'objc': 'OBJCFLAGS',
                        'objcpp': 'OBJCXXFLAGS',
                        'fortran': 'FFLAGS',
                        'd': 'DFLAGS'}
      compile_flags = os.environ.get(cflags_mapping[lang], '')
      log_var(cflags_mapping[lang], compile_flags)
      compile_flags = compile_flags.split()
  
      # Link flags (same for all languages)
      link_flags = os.environ.get('LDFLAGS', '')
      log_var('LDFLAGS', link_flags)
      link_flags = link_flags.split()
      if compiler_is_linker:
          # When the compiler is used as a wrapper around the linker (such as
          # with GCC and Clang), the compile flags can be needed while linking
          # too. This is also what Autotools does. However, we don't want to do
          # this when the linker is stand-alone such as with MSVC C/C++, etc.
          link_flags = compile_flags + link_flags
  
      # Pre-processof rlags (not for fortran)
      preproc_flags = ''
      if lang in ('c', 'cpp', 'objc', 'objcpp'):
          preproc_flags = os.environ.get('CPPFLAGS', '')
      log_var('CPPFLAGS', preproc_flags)
      compile_flags += preproc_flags.split()
  
      return compile_flags, link_flags
  
  class CrossBuildInfo:
  
  
  [... the rest is omitted ...]
files: mesonbuild/environment.py
files: # Copyright 2012-2016 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 os, re, subprocess, platform
  from . import coredata
  from . import mesonlib
  from . import mlog
  from .compilers import *
  from .mesonlib import EnvironmentException, Popen_safe
  import configparser
  import shlex
  import shutil
  
  build_filename = 'meson.build'
  
  def find_coverage_tools():
      gcovr_exe = 'gcovr'
      lcov_exe = 'lcov'
      genhtml_exe = 'genhtml'
  
      if not mesonlib.exe_exists([gcovr_exe, '--version']):
          gcovr_exe = None
      if not mesonlib.exe_exists([lcov_exe, '--version']):
          lcov_exe = None
      if not mesonlib.exe_exists([genhtml_exe, '--version']):
          genhtml_exe = None
      return gcovr_exe, lcov_exe, genhtml_exe
  
  def detect_ninja(version='1.5'):
      for n in ['ninja', 'ninja-build']:
          try:
              p, found = Popen_safe([n, '--version'])[0:2]
          except (FileNotFoundError, PermissionError):
              # Doesn't exist in PATH or isn't executable
              continue
          # Perhaps we should add a way for the caller to know the failure mode
          # (not found or too old)
          if p.returncode == 0 and mesonlib.version_compare(found, '>=' + version):
              return n
  
  def detect_native_windows_arch():
      """
      The architecture of Windows itself: x86 or amd64
      """
      # These env variables are always available. See:
      # https://msdn.microsoft.com/en-us/library/aa384274(VS.85).aspx
      # https://blogs.msdn.microsoft.com/david.wang/2006/03/27/howto-detect-process-bitness/
      arch = os.environ.get('PROCESSOR_ARCHITEW6432', '').lower()
      if not arch:
          try:
              # If this doesn't exist, something is messing with the environment
              arch = os.environ['PROCESSOR_ARCHITECTURE'].lower()
          except KeyError:
              raise EnvironmentException('Unable to detect native OS architecture')
      return arch
  
  def detect_windows_arch(compilers):
      """
      Detecting the 'native' architecture of Windows is not a trivial task. We
      cannot trust that the architecture that Python is built for is the 'native'
      one because you can run 32-bit apps on 64-bit Windows using WOW64 and
      people sometimes install 32-bit Python on 64-bit Windows.
  
      We also can't rely on the architecture of the OS itself, since it's
      perfectly normal to compile and run 32-bit applications on Windows as if
      they were native applications. It's a terrible experience to require the
      user to supply a cross-info file to compile 32-bit applications on 64-bit
      Windows. Thankfully, the only way to compile things with Visual Studio on
      Windows is by entering the 'msvc toolchain' environment, which can be
      easily detected.
  
      In the end, the sanest method is as follows:
      1. Check if we're in an MSVC toolchain environment, and if so, return the
         MSVC toolchain architecture as our 'native' architecture.
      2. If not, check environment variables that are set by Windows and WOW64 to
         find out the architecture that Windows is built for, and use that as our
         'native' architecture.
      """
      os_arch = detect_native_windows_arch()
      if os_arch != 'amd64':
          return os_arch
      # If we're on 64-bit Windows, 32-bit apps can be compiled without
      # cross-compilation. So if we're doing that, just set the native arch as
      # 32-bit and pretend like we're running under WOW64. Else, return the
      # actual Windows architecture that we deduced above.
      for compiler in compilers.values():
          # Check if we're using and inside an MSVC toolchain environment
          if compiler.id == 'msvc' and 'VCINSTALLDIR' in os.environ:
              # 'Platform' is only set when the target arch is not 'x86'.
              # It's 'x64' when targetting x86_64 and 'arm' when targetting ARM.
              platform = os.environ.get('Platform', 'x86').lower()
              if platform == 'x86':
                  return platform
          if compiler.id == 'gcc' and compiler.has_define('__i386__'):
              return 'x86'
      return os_arch
  
  def detect_cpu_family(compilers):
      """
      Python is inconsistent in its platform module.
      It returns different values for the same cpu.
      For x86 it might return 'x86', 'i686' or somesuch.
      Do some canonicalization.
      """
      if mesonlib.is_windows():
          trial = detect_windows_arch(compilers)
      else:
          trial = platform.machine().lower()
      if trial.startswith('i') and trial.endswith('86'):
          return 'x86'
      if trial.startswith('arm'):
          return 'arm'
      if trial in ('amd64', 'x64'):
          trial = 'x86_64'
      if trial == 'x86_64':
          # On Linux (and maybe others) there can be any mixture of 32/64 bit
          # code in the kernel, Python, system etc. The only reliable way
          # to know is to check the compiler defines.
          for c in compilers.values():
              try:
                  if c.has_define('__i386__'):
                      return 'x86'
              except mesonlib.MesonException:
                  # Ignore compilers that do not support has_define.
                  pass
          return 'x86_64'
      # Add fixes here as bugs are reported.
      return trial
  
  def detect_cpu(compilers):
      if mesonlib.is_windows():
          trial = detect_windows_arch(compilers)
      else:
          trial = platform.machine().lower()
      if trial in ('amd64', 'x64'):
          trial = 'x86_64'
      if trial == 'x86_64':
          # Same check as above for cpu_family
          for c in compilers.values():
              try:
                  if c.has_define('__i386__'):
                      return 'i686' # All 64 bit cpus have at least this level of x86 support.
              except mesonlib.MesonException:
                  pass
          return 'x86_64'
      # Add fixes here as bugs are reported.
      return trial
  
  def detect_system():
      return platform.system().lower()
  
  
  def for_windows(is_cross, env):
      """
      Host machine is windows?
  
      Note: 'host' is the machine on which compiled binaries will run
      """
      if not is_cross:
          return mesonlib.is_windows()
      elif env.cross_info.has_host():
          return env.cross_info.config['host_machine']['system'] == 'windows'
      return False
  
  def for_darwin(is_cross, env):
      """
      Host machine is Darwin (iOS/OS X)?
  
      Note: 'host' is the machine on which compiled binaries will run
      """
      if not is_cross:
          return mesonlib.is_osx()
      elif env.cross_info.has_host():
          return env.cross_info.config['host_machine']['system'] == 'darwin'
      return False
  
  
  def search_version(text):
      # Usually of the type 4.1.4 but compiler output may contain
      # stuff like this:
      # (Sourcery CodeBench Lite 2014.05-29) 4.8.3 20140320 (prerelease)
      # Limiting major version number to two digits seems to work
      # thus far. When we get to GCC 100, this will break, but
      # if we are still relevant when that happens, it can be
      # considered an achievement in itself.
      #
      # This regex is reaching magic levels. If it ever needs
      # to be updated, do not complexify but convert to something
      # saner instead.
      version_regex = '(?<!(\d|\.))(\d{1,2}(\.\d+)+(-[a-zA-Z0-9]+)?)'
      match = re.search(version_regex, text)
      if match:
          return match.group(0)
      return 'unknown version'
  
  class Environment:
      private_dir = 'meson-private'
      log_dir = 'meson-logs'
      coredata_file = os.path.join(private_dir, 'coredata.dat')
  
      def __init__(self, source_dir, build_dir, main_script_launcher, options, original_cmd_line_args):
          self.source_dir = source_dir
          self.build_dir = build_dir
          self.meson_script_launcher = main_script_launcher
          self.scratch_dir = os.path.join(build_dir, Environment.private_dir)
          self.log_dir = os.path.join(build_dir, Environment.log_dir)
          os.makedirs(self.scratch_dir, exist_ok=True)
          os.makedirs(self.log_dir, exist_ok=True)
          try:
              cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
              self.coredata = coredata.load(cdf)
              self.first_invocation = False
          except FileNotFoundError:
              # WARNING: Don't use any values from coredata in __init__. It gets
              # re-initialized with project options by the interpreter during
              # build file parsing.
              self.coredata = coredata.CoreData(options)
              self.coredata.meson_script_launcher = self.meson_script_launcher
              self.first_invocation = True
          if self.coredata.cross_file:
              self.cross_info = CrossBuildInfo(self.coredata.cross_file)
          else:
              self.cross_info = None
          self.cmd_line_options = options
          self.original_cmd_line_args = original_cmd_line_args
  
          # List of potential compilers.
          if mesonlib.is_windows():
              self.default_c = ['cl', 'cc', 'gcc', 'clang']
              self.default_cpp = ['cl', 'c++', 'g++', 'clang++']
          else:
              self.default_c = ['cc']
              self.default_cpp = ['c++']
          self.default_objc = ['cc']
          self.default_objcpp = ['c++']
          self.default_fortran = ['gfortran', 'g95', 'f95', 'f90', 'f77']
          self.default_static_linker = 'ar'
          self.vs_static_linker = 'lib'
  
          # Various prefixes and suffixes for import libraries, shared libraries,
          # static libraries, and executables.
          # Versioning is added to these names in the backends as-needed.
          cross = self.is_cross_build()
          if (not cross and mesonlib.is_windows()) \
                  or (cross and self.cross_info.has_host() and self.cross_info.config['host_machine']['system'] == 'windows'):
              self.exe_suffix = 'exe'
              self.object_suffix = 'obj'
              self.win_libdir_layout = True
          else:
              self.exe_suffix = ''
              self.object_suffix = 'o'
              self.win_libdir_layout = False
  
      def is_cross_build(self):
          return self.cross_info is not None
  
      def dump_coredata(self, mtime):
          cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
          coredata.save(self.coredata, cdf)
          os.utime(cdf, times=(mtime, mtime))
  
      def get_script_dir(self):
          import mesonbuild.scripts
          return os.path.dirname(mesonbuild.scripts.__file__)
  
      def get_log_dir(self):
          return self.log_dir
  
      def get_coredata(self):
          return self.coredata
  
      def get_build_command(self):
          return self.meson_script_launcher
  
      def is_header(self, fname):
          return is_header(fname)
  
      def is_source(self, fname):
          return is_source(fname)
  
      def is_assembly(self, fname):
          return is_assembly(fname)
  
      def is_llvm_ir(self, fname):
          return is_llvm_ir(fname)
  
      def is_object(self, fname):
          return is_object(fname)
  
      def is_library(self, fname):
          return is_library(fname)
  
      def had_argument_for(self, option):
          trial1 = '--' + option
          trial2 = '-D' + option
          previous_is_plaind = False
          for i in self.original_cmd_line_args:
              if i.startswith(trial1) or i.startswith(trial2):
                  return True
              if previous_is_plaind and i.startswith(option):
                  return True
              previous_is_plaind = i == '-D'
          return False
  
      def merge_options(self, options):
          for (name, value) in options.items():
              if name not in self.coredata.user_options:
                  self.coredata.user_options[name] = value
              else:
                  oldval = self.coredata.user_options[name]
                  if type(oldval) != type(value):
                      self.coredata.user_options[name] = value
  
      @staticmethod
      def get_gnu_compiler_defines(compiler):
          """
          Detect GNU compiler platform type (Apple, MinGW, Unix)
          """
          # Arguments to output compiler pre-processor defines to stdout
          # gcc, g++, and gfortran all support these arguments
          args = compiler + ['-E', '-dM', '-']
          p, output = Popen_safe(args, write='', stdin=subprocess.PIPE)[0:2]
          if p.returncode != 0:
              raise EnvironmentException('Unable to detect GNU compiler type:\n' + output)
          # Parse several lines of the type:
          # `#define ___SOME_DEF some_value`
          # and extract `___SOME_DEF`
          defines = {}
          for line in output.split('\n'):
              if not line:
                  continue
              d, *rest = line.split(' ', 2)
              if d != '#define':
                  continue
              if len(rest) == 1:
                  defines[rest] = True
              if len(rest) == 2:
                  defines[rest[0]] = rest[1]
          return defines
  
      @staticmethod
      def get_gnu_version_from_defines(defines):
          dot = '.'
          major = defines.get('__GNUC__', '0')
          minor = defines.get('__GNUC_MINOR__', '0')
          patch = defines.get('__GNUC_PATCHLEVEL__', '0')
          return dot.join((major, minor, patch))
  
      @staticmethod
      def get_gnu_compiler_type(defines):
          # Detect GCC type (Apple, MinGW, Cygwin, Unix)
          if '__APPLE__' in defines:
              return GCC_OSX
          elif '__MINGW32__' in defines or '__MINGW64__' in defines:
              return GCC_MINGW
          # We ignore Cygwin for now, and treat it as a standard GCC
          return GCC_STANDARD
  
      def _get_compilers(self, lang, evar, want_cross):
          '''
          The list of compilers is detected in the exact same way for
          C, C++, ObjC, ObjC++, Fortran so consolidate it here.
          '''
          if self.is_cross_build() and want_cross:
              compilers = [mesonlib.stringlistify(self.cross_info.config['binaries'][lang])]
              ccache = []
              is_cross = True
              if self.cross_info.need_exe_wrapper():
                  exe_wrap = self.cross_info.config['binaries'].get('exe_wrapper', None)
              else:
                  exe_wrap = []
          elif evar in os.environ:
              compilers = [shlex.split(os.environ[evar])]
              ccache = []
              is_cross = False
              exe_wrap = None
          else:
              compilers = getattr(self, 'default_' + lang)
              ccache = self.detect_ccache()
              is_cross = False
              exe_wrap = None
          return compilers, ccache, is_cross, exe_wrap
  
      def _handle_compiler_exceptions(self, exceptions, compilers):
          errmsg = 'Unknown compiler(s): ' + str(compilers)
          if exceptions:
              errmsg += '\nThe follow exceptions were encountered:'
              for (c, e) in exceptions.items():
                  errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
          raise EnvironmentException(errmsg)
  
      def detect_c_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('c', 'CC', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  basename = os.path.basename(compiler[-1]).lower()
                  if basename == 'cl' or basename == 'cl.exe':
                      arg = '/?'
                  else:
                      arg = '--version'
                  p, out, err = Popen_safe(compiler + [arg])
              except OSError as e:
                  popen_exceptions[' '.join(compiler + [arg])] = e
                  continue
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  gtype = self.get_gnu_compiler_type(defines)
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuCCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
              if 'clang' in out:
                  if 'Apple' in out or for_darwin(want_cross, self):
                      cltype = CLANG_OSX
                  else:
                      cltype = CLANG_STANDARD
                  return ClangCCompiler(ccache + compiler, version, cltype, is_cross, exe_wrap)
              if 'Microsoft' in out or 'Microsoft' in err:
                  # Visual Studio prints version number to stderr but
                  # everything else to stdout. Why? Lord only knows.
                  version = search_version(err)
                  return VisualStudioCCompiler(compiler, version, is_cross, exe_wrap)
              if '(ICC)' in out:
                  # TODO: add microsoft add check OSX
                  inteltype = ICC_STANDARD
                  return IntelCCompiler(ccache + compiler, version, inteltype, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_fortran_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('fortran', 'FC', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              for arg in ['--version', '-V']:
                  try:
                      p, out, err = Popen_safe(compiler + [arg])
                  except OSError as e:
                      popen_exceptions[' '.join(compiler + [arg])] = e
                      continue
  
                  version = search_version(out)
  
                  if 'GNU Fortran' in out:
                      defines = self.get_gnu_compiler_defines(compiler)
                      if not defines:
                          popen_exceptions[compiler] = 'no pre-processor defines'
                          continue
                      gtype = self.get_gnu_compiler_type(defines)
                      version = self.get_gnu_version_from_defines(defines)
                      return GnuFortranCompiler(compiler, version, gtype, is_cross, exe_wrap, defines)
  
                  if 'G95' in out:
                      return G95FortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'Sun Fortran' in err:
                      version = search_version(err)
                      return SunFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'ifort (IFORT)' in out:
                      return IntelFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'PathScale EKOPath(tm)' in err:
                      return PathScaleFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'PGI Compilers' in out:
                      return PGIFortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'Open64 Compiler Suite' in err:
                      return Open64FortranCompiler(compiler, version, is_cross, exe_wrap)
  
                  if 'NAG Fortran' in err:
                      return NAGFortranCompiler(compiler, version, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def get_scratch_dir(self):
          return self.scratch_dir
  
      def get_depfixer(self):
          path = os.path.split(__file__)[0]
          return os.path.join(path, 'depfixer.py')
  
      def detect_cpp_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('cpp', 'CXX', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              basename = os.path.basename(compiler[-1]).lower()
              if basename == 'cl' or basename == 'cl.exe':
                  arg = '/?'
              else:
                  arg = '--version'
              try:
                  p, out, err = Popen_safe(compiler + [arg])
              except OSError as e:
                  popen_exceptions[' '.join(compiler + [arg])] = e
                  continue
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  gtype = self.get_gnu_compiler_type(defines)
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuCPPCompiler(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
              if 'clang' in out:
                  if 'Apple' in out:
                      cltype = CLANG_OSX
                  else:
                      cltype = CLANG_STANDARD
                  return ClangCPPCompiler(ccache + compiler, version, cltype, is_cross, exe_wrap)
              if 'Microsoft' in out or 'Microsoft' in err:
                  version = search_version(err)
                  return VisualStudioCPPCompiler(compiler, version, is_cross, exe_wrap)
              if '(ICC)' in out:
                  # TODO: add microsoft add check OSX
                  inteltype = ICC_STANDARD
                  return IntelCPPCompiler(ccache + compiler, version, inteltype, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_objc_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('objc', 'OBJC', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  p, out, err = Popen_safe(compiler + ['--version'])
              except OSError:
                  popen_exceptions[' '.join(compiler + [arg])] = e
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuObjCCompiler(ccache + compiler, version, is_cross, exe_wrap, defines)
              if out.startswith('Apple LLVM'):
                  return ClangObjCCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
              if out.startswith('clang'):
                  return ClangObjCCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_objcpp_compiler(self, want_cross):
          popen_exceptions = {}
          compilers, ccache, is_cross, exe_wrap = self._get_compilers('objcpp', 'OBJCXX', want_cross)
          for compiler in compilers:
              if isinstance(compiler, str):
                  compiler = [compiler]
              try:
                  p, out, err = Popen_safe(compiler + ['--version'])
              except OSError:
                  popen_exceptions[' '.join(compiler + [arg])] = e
              version = search_version(out)
              if 'Free Software Foundation' in out:
                  defines = self.get_gnu_compiler_defines(compiler)
                  if not defines:
                      popen_exceptions[compiler] = 'no pre-processor defines'
                      continue
                  version = self.get_gnu_version_from_defines(defines)
                  return GnuObjCPPCompiler(ccache + compiler, version, is_cross, exe_wrap, defines)
              if out.startswith('Apple LLVM'):
                  return ClangObjCPPCompiler(ccache + compiler, version, CLANG_OSX, is_cross, exe_wrap)
              if out.startswith('clang'):
                  return ClangObjCPPCompiler(ccache + compiler, version, CLANG_STANDARD, is_cross, exe_wrap)
          self._handle_compiler_exceptions(popen_exceptions, compilers)
  
      def detect_java_compiler(self):
          exelist = ['javac']
          try:
              p, out, err = Popen_safe(exelist + ['-version'])
          except OSError:
              raise EnvironmentException('Could not execute Java compiler "%s"' % ' '.join(exelist))
          version = search_version(err)
          if 'javac' in err:
              return JavaCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_cs_compiler(self):
          exelist = ['mcs']
          try:
              p, out, err = Popen_safe(exelist + ['--version'])
          except OSError:
              raise EnvironmentException('Could not execute C# compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'Mono' in out:
              return MonoCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_vala_compiler(self):
          exelist = ['valac']
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute Vala compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'Vala' in out:
              return ValaCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_rust_compiler(self):
          exelist = ['rustc']
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute Rust compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'rustc' in out:
              return RustCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_d_compiler(self, want_cross):
          is_cross = False
          # Search for a D compiler.
          # We prefer LDC over GDC unless overridden with the DC
          # environment variable because LDC has a much more
          # up to date language version at time (2016).
          if 'DC' in os.environ:
              exelist = shlex.split(os.environ['DC'])
          elif self.is_cross_build() and want_cross:
              exelist = mesonlib.stringlistify(self.cross_info.config['binaries']['d'])
              is_cross = True
          elif shutil.which("ldc2"):
              exelist = ['ldc2']
          elif shutil.which("ldc"):
              exelist = ['ldc']
          elif shutil.which("gdc"):
              exelist = ['gdc']
          elif shutil.which("dmd"):
              exelist = ['dmd']
          else:
              raise EnvironmentException('Could not find any supported D compiler.')
  
          try:
              p, out = Popen_safe(exelist + ['--version'])[0:2]
          except OSError:
              raise EnvironmentException('Could not execute D compiler "%s"' % ' '.join(exelist))
          version = search_version(out)
          if 'LLVM D compiler' in out:
              return LLVMDCompiler(exelist, version, is_cross)
          elif 'gdc' in out:
              return GnuDCompiler(exelist, version, is_cross)
          elif 'Digital Mars' in out:
              return DmdDCompiler(exelist, version, is_cross)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_swift_compiler(self):
          exelist = ['swiftc']
          try:
              p, _, err = Popen_safe(exelist + ['-v'])
          except OSError:
              raise EnvironmentException('Could not execute Swift compiler "%s"' % ' '.join(exelist))
          version = search_version(err)
          if 'Swift' in err:
              return SwiftCompiler(exelist, version)
          raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')
  
      def detect_static_linker(self, compiler):
          if compiler.is_cross:
              linker = self.cross_info.config['binaries']['ar']
              if isinstance(linker, str):
                  linker = [linker]
          else:
              evar = 'AR'
              if evar in os.environ:
                  linker = shlex.split(os.environ[evar])
              elif isinstance(compiler, VisualStudioCCompiler):
                  linker = [self.vs_static_linker]
              else:
                  linker = [self.default_static_linker]
          basename = os.path.basename(linker[-1]).lower()
          if basename == 'lib' or basename == 'lib.exe':
              arg = '/?'
          else:
              arg = '--version'
          try:
              p, out, err = Popen_safe(linker + [arg])
          except OSError:
              raise EnvironmentException('Could not execute static linker "%s".' % ' '.join(linker))
          if '/OUT:' in out or '/OUT:' in err:
              return VisualStudioLinker(linker)
          if p.returncode == 0:
              return ArLinker(linker)
          if p.returncode == 1 and err.startswith('usage'): # OSX
              return ArLinker(linker)
          raise EnvironmentException('Unknown static linker "%s"' % ' '.join(linker))
  
      def detect_ccache(self):
          try:
              has_ccache = subprocess.call(['ccache', '--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
          except OSError:
              has_ccache = 1
          if has_ccache == 0:
              cmdlist = ['ccache']
          else:
              cmdlist = []
          return cmdlist
  
      def get_source_dir(self):
          return self.source_dir
  
      def get_build_dir(self):
          return self.build_dir
  
      def get_exe_suffix(self):
          return self.exe_suffix
  
      def get_import_lib_dir(self):
          "Install dir for the import library (library used for linking)"
          return self.get_libdir()
  
      def get_shared_lib_dir(self):
          "Install dir for the shared library"
          if self.win_libdir_layout:
              return self.get_bindir()
          return self.get_libdir()
  
      def get_static_lib_dir(self):
          "Install dir for the static library"
          return self.get_libdir()
  
      def get_object_suffix(self):
          return self.object_suffix
  
      def get_prefix(self):
          return self.coredata.get_builtin_option('prefix')
  
      def get_libdir(self):
          return self.coredata.get_builtin_option('libdir')
  
      def get_libexecdir(self):
          return self.coredata.get_builtin_option('libexecdir')
  
      def get_bindir(self):
          return self.coredata.get_builtin_option('bindir')
  
      def get_includedir(self):
          return self.coredata.get_builtin_option('includedir')
  
      def get_mandir(self):
          return self.coredata.get_builtin_option('mandir')
  
      def get_datadir(self):
          return self.coredata.get_builtin_option('datadir')
  
  
  def get_args_from_envvars(compiler):
      """
      @compiler: Compiler to fetch environment flags for
  
      Returns a tuple of (compile_flags, link_flags) for the specified language
      from the inherited environment
      """
      def log_var(var, val):
          if val:
              mlog.log('Appending {} from environment: {!r}'.format(var, val))
  
      lang = compiler.get_language()
      compiler_is_linker = False
      if hasattr(compiler, 'get_linker_exelist'):
          compiler_is_linker = (compiler.get_exelist() == compiler.get_linker_exelist())
  
      if lang not in ('c', 'cpp', 'objc', 'objcpp', 'fortran', 'd'):
          return [], []
  
      # Compile flags
      cflags_mapping = {'c': 'CFLAGS',
                        'cpp': 'CXXFL
  
  [... the rest is omitted ...]
files: mesonbuild/environment.py