scons/gallium.py

   1 """gallium
   2
   3 Frontend-tool for Gallium3D architecture.
   4
   5 """
   6
   7 #
   8 # Copyright 2008 VMware, Inc.
   9 # All Rights Reserved.
  10 #
  11 # Permission is hereby granted, free of charge, to any person obtaining a
  12 # copy of this software and associated documentation files (the
  13 # "Software"), to deal in the Software without restriction, including
  14 # without limitation the rights to use, copy, modify, merge, publish,
  15 # distribute, sub license, and/or sell copies of the Software, and to
  16 # permit persons to whom the Software is furnished to do so, subject to
  17 # the following conditions:
  18 #
  19 # The above copyright notice and this permission notice (including the
  20 # next paragraph) shall be included in all copies or substantial portions
  21 # of the Software.
  22 #
  23 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  24 # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  26 # IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  27 # ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  28 # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  29 # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 #
  31
  32
  33 import distutils.version
  34 import os
  35 import os.path
  36 import re
  37 import subprocess
  38 import platform as host_platform
  39 import sys
  40 import tempfile
  41
  42 import SCons.Action
  43 import SCons.Builder
  44 import SCons.Scanner
  45
  46
  47 def symlink(target, source, env):
  48     target = str(target[0])
  49     source = str(source[0])
  50     if os.path.islink(target) or os.path.exists(target):
  51         os.remove(target)
  52     os.symlink(os.path.basename(source), target)
  53
  54 def install(env, source, subdir):
  55     target_dir = os.path.join(env.Dir('#.').srcnode().abspath, env['build_dir'], subdir)
  56     return env.Install(target_dir, source)
  57
  58 def install_program(env, source):
  59     return install(env, source, 'bin')
  60
  61 def install_shared_library(env, sources, version = ()):
  62     targets = []
  63     install_dir = os.path.join(env.Dir('#.').srcnode().abspath, env['build_dir'])
  64     version = tuple(map(str, version))
  65     if env['SHLIBSUFFIX'] == '.dll':
  66         dlls = env.FindIxes(sources, 'SHLIBPREFIX', 'SHLIBSUFFIX')
  67         targets += install(env, dlls, 'bin')
  68         libs = env.FindIxes(sources, 'LIBPREFIX', 'LIBSUFFIX')
  69         targets += install(env, libs, 'lib')
  70     else:
  71         for source in sources:
  72             target_dir =  os.path.join(install_dir, 'lib')
  73             target_name = '.'.join((str(source),) + version)
  74             last = env.InstallAs(os.path.join(target_dir, target_name), source)
  75             targets += last
  76             while len(version):
  77                 version = version[:-1]
  78                 target_name = '.'.join((str(source),) + version)
  79                 action = SCons.Action.Action(symlink, "  Symlinking $TARGET ...")
  80                 last = env.Command(os.path.join(target_dir, target_name), last, action)
  81                 targets += last
  82     return targets
  83
  84
  85 def createInstallMethods(env):
  86     env.AddMethod(install_program, 'InstallProgram')
  87     env.AddMethod(install_shared_library, 'InstallSharedLibrary')
  88
  89
  90 def msvc2013_compat(env):
  91     if env['gcc']:
  92         env.Append(CCFLAGS = [
  93             '-Werror=vla',
  94             '-Werror=pointer-arith',
  95         ])
  96
  97 def msvc2008_compat(env):
  98     msvc2013_compat(env)
  99     if env['gcc']:
 100         env.Append(CFLAGS = [
 101             '-Werror=declaration-after-statement',
 102         ])
 103
 104 def createMSVCCompatMethods(env):
 105     env.AddMethod(msvc2013_compat, 'MSVC2013Compat')
 106     env.AddMethod(msvc2008_compat, 'MSVC2008Compat')
 107
 108
 109 def num_jobs():
 110     try:
 111         return int(os.environ['NUMBER_OF_PROCESSORS'])
 112     except (ValueError, KeyError):
 113         pass
 114
 115     try:
 116         return os.sysconf('SC_NPROCESSORS_ONLN')
 117     except (ValueError, OSError, AttributeError):
 118         pass
 119
 120     try:
 121         return int(os.popen2("sysctl -n hw.ncpu")[1].read())
 122     except ValueError:
 123         pass
 124
 125     return 1
 126
 127
 128 def check_cc(env, cc, expr, cpp_opt = '-E'):
 129     # Invoke C-preprocessor to determine whether the specified expression is
 130     # true or not.
 131
 132     sys.stdout.write('Checking for %s ... ' % cc)
 133
 134     source = tempfile.NamedTemporaryFile(suffix='.c', delete=False)
 135     source.write('#if !(%s)\n#error\n#endif\n' % expr)
 136     source.close()
 137
 138     pipe = SCons.Action._subproc(env, [env['CC'], cpp_opt, source.name],
 139                                  stdin = 'devnull',
 140                                  stderr = 'devnull',
 141                                  stdout = 'devnull')
 142     result = pipe.wait() == 0
 143
 144     os.unlink(source.name)
 145
 146     sys.stdout.write(' %s\n' % ['no', 'yes'][int(bool(result))])
 147     return result
 148
 149
 150 def check_prog(env, prog):
 151     """Check whether this program exists."""
 152
 153     sys.stdout.write('Checking for %s ... ' % prog)
 154
 155     result = env.Detect(prog)
 156
 157     sys.stdout.write(' %s\n' % ['no', 'yes'][int(bool(result))])
 158     return result
 159
 160
 161 def generate(env):
 162     """Common environment generation code"""
 163
 164     # Tell tools which machine to compile for
 165     env['TARGET_ARCH'] = env['machine']
 166     env['MSVS_ARCH'] = env['machine']
 167
 168     # Toolchain
 169     platform = env['platform']
 170     env.Tool(env['toolchain'])
 171
 172     # Allow override compiler and specify additional flags from environment
 173     if os.environ.has_key('CC'):
 174         env['CC'] = os.environ['CC']
 175         # Update CCVERSION to match
 176         pipe = SCons.Action._subproc(env, [env['CC'], '--version'],
 177                                      stdin = 'devnull',
 178                                      stderr = 'devnull',
 179                                      stdout = subprocess.PIPE)
 180         if pipe.wait() == 0:
 181             line = pipe.stdout.readline()
 182             match = re.search(r'[0-9]+(\.[0-9]+)+', line)
 183             if match:
 184                 env['CCVERSION'] = match.group(0)
 185     if os.environ.has_key('CFLAGS'):
 186         env['CCFLAGS'] += SCons.Util.CLVar(os.environ['CFLAGS'])
 187     if os.environ.has_key('CXX'):
 188         env['CXX'] = os.environ['CXX']
 189     if os.environ.has_key('CXXFLAGS'):
 190         env['CXXFLAGS'] += SCons.Util.CLVar(os.environ['CXXFLAGS'])
 191     if os.environ.has_key('LDFLAGS'):
 192         env['LINKFLAGS'] += SCons.Util.CLVar(os.environ['LDFLAGS'])
 193
 194     # Detect gcc/clang not by executable name, but through pre-defined macros
 195     # as autoconf does, to avoid drawing wrong conclusions when using tools
 196     # that overrice CC/CXX like scan-build.
 197     env['gcc'] = 0
 198     env['clang'] = 0
 199     env['msvc'] = 0
 200     if host_platform.system() == 'Windows':
 201         env['msvc'] = check_cc(env, 'MSVC', 'defined(_MSC_VER)', '/E')
 202     if not env['msvc']:
 203         env['gcc'] = check_cc(env, 'GCC', 'defined(__GNUC__) && !defined(__clang__)')
 204         env['clang'] = check_cc(env, 'Clang', '__clang__')
 205     env['suncc'] = env['platform'] == 'sunos' and os.path.basename(env['CC']) == 'cc'
 206     env['icc'] = 'icc' == os.path.basename(env['CC'])
 207
 208     if env['msvc'] and env['toolchain'] == 'default' and env['machine'] == 'x86_64':
 209         # MSVC x64 support is broken in earlier versions of scons
 210         env.EnsurePythonVersion(2, 0)
 211
 212     # shortcuts
 213     machine = env['machine']
 214     platform = env['platform']
 215     x86 = env['machine'] == 'x86'
 216     ppc = env['machine'] == 'ppc'
 217     gcc_compat = env['gcc'] or env['clang']
 218     msvc = env['msvc']
 219     suncc = env['suncc']
 220     icc = env['icc']
 221
 222     # Determine whether we are cross compiling; in particular, whether we need
 223     # to compile code generators with a different compiler as the target code.
 224     hosthost_platform = host_platform.system().lower()
 225     if hosthost_platform.startswith('cygwin'):
 226         hosthost_platform = 'cygwin'
 227     host_machine = os.environ.get('PROCESSOR_ARCHITEW6432', os.environ.get('PROCESSOR_ARCHITECTURE', host_platform.machine()))
 228     host_machine = {
 229         'x86': 'x86',
 230         'i386': 'x86',
 231         'i486': 'x86',
 232         'i586': 'x86',
 233         'i686': 'x86',
 234         'ppc' : 'ppc',
 235         'AMD64': 'x86_64',
 236         'x86_64': 'x86_64',
 237     }.get(host_machine, 'generic')
 238     env['crosscompile'] = platform != hosthost_platform
 239     if machine == 'x86_64' and host_machine != 'x86_64':
 240         env['crosscompile'] = True
 241     env['hostonly'] = False
 242
 243     # Backwards compatability with the debug= profile= options
 244     if env['build'] == 'debug':
 245         if not env['debug']:
 246             print 'scons: warning: debug option is deprecated and will be removed eventually; use instead'
 247             print
 248             print ' scons build=release'
 249             print
 250             env['build'] = 'release'
 251         if env['profile']:
 252             print 'scons: warning: profile option is deprecated and will be removed eventually; use instead'
 253             print
 254             print ' scons build=profile'
 255             print
 256             env['build'] = 'profile'
 257     if False:
 258         # Enforce SConscripts to use the new build variable
 259         env.popitem('debug')
 260         env.popitem('profile')
 261     else:
 262         # Backwards portability with older sconscripts
 263         if env['build'] in ('debug', 'checked'):
 264             env['debug'] = True
 265             env['profile'] = False
 266         if env['build'] == 'profile':
 267             env['debug'] = False
 268             env['profile'] = True
 269         if env['build'] == 'release':
 270             env['debug'] = False
 271             env['profile'] = False
 272
 273     # Put build output in a separate dir, which depends on the current
 274     # configuration. See also http://www.scons.org/wiki/AdvancedBuildExample
 275     build_topdir = 'build'
 276     build_subdir = env['platform']
 277     if env['embedded']:
 278         build_subdir =  'embedded-' + build_subdir
 279     if env['machine'] != 'generic':
 280         build_subdir += '-' + env['machine']
 281     if env['build'] != 'release':
 282         build_subdir += '-' +  env['build']
 283     build_dir = os.path.join(build_topdir, build_subdir)
 284     # Place the .sconsign file in the build dir too, to avoid issues with
 285     # different scons versions building the same source file
 286     env['build_dir'] = build_dir
 287     env.SConsignFile(os.path.join(build_dir, '.sconsign'))
 288     if 'SCONS_CACHE_DIR' in os.environ:
 289         print 'scons: Using build cache in %s.' % (os.environ['SCONS_CACHE_DIR'],)
 290         env.CacheDir(os.environ['SCONS_CACHE_DIR'])
 291     env['CONFIGUREDIR'] = os.path.join(build_dir, 'conf')
 292     env['CONFIGURELOG'] = os.path.join(os.path.abspath(build_dir), 'config.log')
 293
 294     # Parallel build
 295     if env.GetOption('num_jobs') <= 1:
 296         env.SetOption('num_jobs', num_jobs())
 297
 298     env.Decider('MD5-timestamp')
 299     env.SetOption('max_drift', 60)
 300
 301     # C preprocessor options
 302     cppdefines = []
 303     cppdefines += ['__STDC_LIMIT_MACROS', '__STDC_CONSTANT_MACROS']
 304     if env['build'] in ('debug', 'checked'):
 305         cppdefines += ['DEBUG']
 306     else:
 307         cppdefines += ['NDEBUG']
 308     if env['build'] == 'profile':
 309         cppdefines += ['PROFILE']
 310     if env['platform'] in ('posix', 'linux', 'freebsd', 'darwin'):
 311         cppdefines += [
 312             '_POSIX_SOURCE',
 313             ('_POSIX_C_SOURCE', '199309L'),
 314             '_SVID_SOURCE',
 315             '_BSD_SOURCE',
 316             '_GNU_SOURCE',
 317             '_DEFAULT_SOURCE',
 318             'HAVE_PTHREAD',
 319             'HAVE_POSIX_MEMALIGN',
 320         ]
 321         if env['platform'] == 'darwin':
 322             cppdefines += [
 323                 '_DARWIN_C_SOURCE',
 324                 'GLX_USE_APPLEGL',
 325                 'GLX_DIRECT_RENDERING',
 326             ]
 327         else:
 328             cppdefines += [
 329                 'GLX_DIRECT_RENDERING',
 330                 'GLX_INDIRECT_RENDERING',
 331             ]
 332         if env['platform'] in ('linux', 'freebsd'):
 333             cppdefines += ['HAVE_ALIAS']
 334         else:
 335             cppdefines += ['GLX_ALIAS_UNSUPPORTED']
 336
 337         if env['platform'] in ('linux', 'darwin'):
 338             cppdefines += ['HAVE_XLOCALE_H']
 339
 340     if env['platform'] == 'haiku':
 341         cppdefines += [
 342             'HAVE_PTHREAD',
 343             'HAVE_POSIX_MEMALIGN'
 344         ]
 345     if platform == 'windows':
 346         cppdefines += [
 347             'WIN32',
 348             '_WINDOWS',
 349             #'_UNICODE',
 350             #'UNICODE',
 351             # http://msdn.microsoft.com/en-us/library/aa383745.aspx
 352             ('_WIN32_WINNT', '0x0601'),
 353             ('WINVER', '0x0601'),
 354         ]
 355         if gcc_compat:
 356             cppdefines += [('__MSVCRT_VERSION__', '0x0700')]
 357         if msvc:
 358             cppdefines += [
 359                 'VC_EXTRALEAN',
 360                 '_USE_MATH_DEFINES',
 361                 '_CRT_SECURE_NO_WARNINGS',
 362                 '_CRT_SECURE_NO_DEPRECATE',
 363                 '_SCL_SECURE_NO_WARNINGS',
 364                 '_SCL_SECURE_NO_DEPRECATE',
 365                 '_ALLOW_KEYWORD_MACROS',
 366                 '_HAS_EXCEPTIONS=0', # Tell C++ STL to not use exceptions
 367             ]
 368         if env['build'] in ('debug', 'checked'):
 369             cppdefines += ['_DEBUG']
 370     if platform == 'windows':
 371         cppdefines += ['PIPE_SUBSYSTEM_WINDOWS_USER']
 372     if env['embedded']:
 373         cppdefines += ['PIPE_SUBSYSTEM_EMBEDDED']
 374     if env['texture_float']:
 375         print 'warning: Floating-point textures enabled.'
 376         print 'warning: Please consult docs/patents.txt with your lawyer before building Mesa.'
 377         cppdefines += ['TEXTURE_FLOAT_ENABLED']
 378     if gcc_compat:
 379         ccversion = env['CCVERSION']
 380         cppdefines += [
 381             'HAVE___BUILTIN_EXPECT',
 382             'HAVE___BUILTIN_FFS',
 383             'HAVE___BUILTIN_FFSLL',
 384             'HAVE_FUNC_ATTRIBUTE_FLATTEN',
 385             'HAVE_FUNC_ATTRIBUTE_UNUSED',
 386             # GCC 3.0
 387             'HAVE_FUNC_ATTRIBUTE_FORMAT',
 388             'HAVE_FUNC_ATTRIBUTE_PACKED',
 389             # GCC 3.4
 390             'HAVE___BUILTIN_CTZ',
 391             'HAVE___BUILTIN_POPCOUNT',
 392             'HAVE___BUILTIN_POPCOUNTLL',
 393             'HAVE___BUILTIN_CLZ',
 394             'HAVE___BUILTIN_CLZLL',
 395         ]
 396         if distutils.version.LooseVersion(ccversion) >= distutils.version.LooseVersion('4.5'):
 397             cppdefines += ['HAVE___BUILTIN_UNREACHABLE']
 398     env.Append(CPPDEFINES = cppdefines)
 399
 400     # C compiler options
 401     cflags = [] # C
 402     cxxflags = [] # C++
 403     ccflags = [] # C & C++
 404     if gcc_compat:
 405         ccversion = env['CCVERSION']
 406         if env['build'] == 'debug':
 407             ccflags += ['-O0']
 408         elif env['gcc'] and ccversion.startswith('4.2.'):
 409             # gcc 4.2.x optimizer is broken
 410             print "warning: gcc 4.2.x optimizer is broken -- disabling optimizations"
 411             ccflags += ['-O0']
 412         else:
 413             ccflags += ['-O3']
 414         if env['gcc']:
 415             # gcc's builtin memcmp is slower than glibc's
 416             # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052
 417             ccflags += ['-fno-builtin-memcmp']
 418         # Work around aliasing bugs - developers should comment this out
 419         ccflags += ['-fno-strict-aliasing']
 420         ccflags += ['-g']
 421         if env['build'] in ('checked', 'profile'):
 422             # See http://code.google.com/p/jrfonseca/wiki/Gprof2Dot#Which_options_should_I_pass_to_gcc_when_compiling_for_profiling?
 423             ccflags += [
 424                 '-fno-omit-frame-pointer',
 425             ]
 426             if env['gcc']:
 427                 ccflags += ['-fno-optimize-sibling-calls']
 428         if env['machine'] == 'x86':
 429             ccflags += [
 430                 '-m32',
 431                 #'-march=pentium4',
 432             ]
 433             if platform != 'haiku':
 434                 # NOTE: We need to ensure stack is realigned given that we
 435                 # produce shared objects, and have no control over the stack
 436                 # alignment policy of the application. Therefore we need
 437                 # -mstackrealign ore -mincoming-stack-boundary=2.
 438                 #
 439                 # XXX: We could have SSE without -mstackrealign if we always used
 440                 # __attribute__((force_align_arg_pointer)), but that's not
 441                 # always the case.
 442                 ccflags += [
 443                     '-mstackrealign', # ensure stack is aligned
 444                     '-msse', '-msse2', # enable SIMD intrinsics
 445                     '-mfpmath=sse', # generate SSE floating-point arithmetic
 446                 ]
 447             if platform in ['windows', 'darwin']:
 448                 # Workaround http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216
 449                 ccflags += ['-fno-common']
 450             if platform in ['haiku']:
 451                 # Make optimizations compatible with Pentium or higher on Haiku
 452                 ccflags += [
 453                     '-mstackrealign', # ensure stack is aligned
 454                     '-march=i586', # Haiku target is Pentium
 455                     '-mtune=i686' # use i686 where we can
 456                 ]
 457         if env['machine'] == 'x86_64':
 458             ccflags += ['-m64']
 459             if platform == 'darwin':
 460                 ccflags += ['-fno-common']
 461         if env['platform'] not in ('cygwin', 'haiku', 'windows'):
 462             ccflags += ['-fvisibility=hidden']
 463         # See also:
 464         # - http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
 465         ccflags += [
 466             '-Wall',
 467             '-Wno-long-long',
 468             '-fmessage-length=0', # be nice to Eclipse
 469         ]
 470         cflags += [
 471             '-Wmissing-prototypes',
 472             '-std=gnu99',
 473         ]
 474     if icc:
 475         cflags += [
 476             '-std=gnu99',
 477         ]
 478     if msvc:
 479         # See also:
 480         # - http://msdn.microsoft.com/en-us/library/19z1t1wy.aspx
 481         # - cl /?
 482         if 'MSVC_VERSION' not in env or distutils.version.LooseVersion(env['MSVC_VERSION']) < distutils.version.LooseVersion('12.0'):
 483             # Use bundled stdbool.h and stdint.h headers for older MSVC
 484             # versions.  stdint.h was introduced in MSVC 2010, but stdbool.h
 485             # was only introduced in MSVC 2013.
 486             top_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
 487             env.Append(CPPPATH = [os.path.join(top_dir, 'include/c99')])
 488         if env['build'] == 'debug':
 489             ccflags += [
 490               '/Od', # disable optimizations
 491               '/Oi', # enable intrinsic functions
 492             ]
 493         else:
 494             if 'MSVC_VERSION' in env and distutils.version.LooseVersion(env['MSVC_VERSION']) < distutils.version.LooseVersion('11.0'):
 495                 print 'scons: warning: Visual Studio versions prior to 2012 are known to produce incorrect code when optimizations are enabled ( https://bugs.freedesktop.org/show_bug.cgi?id=58718 )'
 496             ccflags += [
 497                 '/O2', # optimize for speed
 498             ]
 499         if env['build'] == 'release':
 500             ccflags += [
 501                 '/GL', # enable whole program optimization
 502             ]
 503         else:
 504             ccflags += [
 505                 '/Oy-', # disable frame pointer omission
 506                 '/GL-', # disable whole program optimization
 507             ]
 508         ccflags += [
 509             '/W3', # warning level
 510             '/wd4018', # signed/unsigned mismatch
 511             '/wd4056', # overflow in floating-point constant arithmetic
 512             '/wd4244', # conversion from 'type1' to 'type2', possible loss of data
 513             '/wd4267', # 'var' : conversion from 'size_t' to 'type', possible loss of data
 514             '/wd4305', # truncation from 'type1' to 'type2'
 515             '/wd4351', # new behavior: elements of array 'array' will be default initialized
 516             '/wd4756', # overflow in constant arithmetic
 517             '/wd4800', # forcing value to bool 'true' or 'false' (performance warning)
 518             '/wd4996', # disable deprecated POSIX name warnings
 519         ]
 520         if env['machine'] == 'x86':
 521             ccflags += [
 522                 '/arch:SSE2', # use the SSE2 instructions (default since MSVC 2012)
 523             ]
 524         if platform == 'windows':
 525             ccflags += [
 526                 # TODO
 527             ]
 528         # Automatic pdb generation
 529         # See http://scons.tigris.org/issues/show_bug.cgi?id=1656
 530         env.EnsureSConsVersion(0, 98, 0)
 531         env['PDB'] = '${TARGET.base}.pdb'
 532     env.Append(CCFLAGS = ccflags)
 533     env.Append(CFLAGS = cflags)
 534     env.Append(CXXFLAGS = cxxflags)
 535
 536     if env['platform'] == 'windows' and msvc:
 537         # Choose the appropriate MSVC CRT
 538         # http://msdn.microsoft.com/en-us/library/2kzt1wy3.aspx
 539         if env['build'] in ('debug', 'checked'):
 540             env.Append(CCFLAGS = ['/MTd'])
 541             env.Append(SHCCFLAGS = ['/LDd'])
 542         else:
 543             env.Append(CCFLAGS = ['/MT'])
 544             env.Append(SHCCFLAGS = ['/LD'])
 545
 546     # Static code analysis
 547     if env['analyze']:
 548         if env['msvc']:
 549             # http://msdn.microsoft.com/en-us/library/ms173498.aspx
 550             env.Append(CCFLAGS = [
 551                 '/analyze',
 552                 #'/analyze:log', '${TARGET.base}.xml',
 553                 '/wd28251', # Inconsistent annotation for function
 554             ])
 555         if env['clang']:
 556             # scan-build will produce more comprehensive output
 557             env.Append(CCFLAGS = ['--analyze'])
 558
 559     # Assembler options
 560     if gcc_compat:
 561         if env['machine'] == 'x86':
 562             env.Append(ASFLAGS = ['-m32'])
 563         if env['machine'] == 'x86_64':
 564             env.Append(ASFLAGS = ['-m64'])
 565
 566     # Linker options
 567     linkflags = []
 568     shlinkflags = []
 569     if gcc_compat:
 570         if env['machine'] == 'x86':
 571             linkflags += ['-m32']
 572         if env['machine'] == 'x86_64':
 573             linkflags += ['-m64']
 574         if env['platform'] not in ('darwin'):
 575             shlinkflags += [
 576                 '-Wl,-Bsymbolic',
 577             ]
 578         # Handle circular dependencies in the libraries
 579         if env['platform'] in ('darwin'):
 580             pass
 581         else:
 582             env['_LIBFLAGS'] = '-Wl,--start-group ' + env['_LIBFLAGS'] + ' -Wl,--end-group'
 583         if env['platform'] == 'windows':
 584             linkflags += [
 585                 '-Wl,--nxcompat', # DEP
 586                 '-Wl,--dynamicbase', # ASLR
 587             ]
 588             # Avoid depending on gcc runtime DLLs
 589             linkflags += ['-static-libgcc']
 590             if 'w64' in env['CC'].split('-'):
 591                 linkflags += ['-static-libstdc++']
 592             # Handle the @xx symbol munging of DLL exports
 593             shlinkflags += ['-Wl,--enable-stdcall-fixup']
 594             #shlinkflags += ['-Wl,--kill-at']
 595     if msvc:
 596         if env['build'] == 'release':
 597             # enable Link-time Code Generation
 598             linkflags += ['/LTCG']
 599             env.Append(ARFLAGS = ['/LTCG'])
 600     if platform == 'windows' and msvc:
 601         # See also:
 602         # - http://msdn2.microsoft.com/en-us/library/y0zzbyt4.aspx
 603         linkflags += [
 604             '/fixed:no',
 605             '/incremental:no',
 606             '/dynamicbase', # ASLR
 607             '/nxcompat', # DEP
 608         ]
 609     env.Append(LINKFLAGS = linkflags)
 610     env.Append(SHLINKFLAGS = shlinkflags)
 611
 612     # We have C++ in several libraries, so always link with the C++ compiler
 613     if gcc_compat:
 614         env['LINK'] = env['CXX']
 615
 616     # Default libs
 617     libs = []
 618     if env['platform'] in ('darwin', 'freebsd', 'linux', 'posix', 'sunos'):
 619         libs += ['m', 'pthread', 'dl']
 620     if env['platform'] in ('linux',):
 621         libs += ['rt']
 622     if env['platform'] in ('haiku'):
 623         libs += ['root', 'be', 'network', 'translation']
 624     env.Append(LIBS = libs)
 625
 626     # OpenMP
 627     if env['openmp']:
 628         if env['msvc']:
 629             env.Append(CCFLAGS = ['/openmp'])
 630             # When building openmp release VS2008 link.exe crashes with LNK1103 error.
 631             # Workaround: overwrite PDB flags with empty value as it isn't required anyways
 632             if env['build'] == 'release':
 633                 env['PDB'] = ''
 634         if env['gcc']:
 635             env.Append(CCFLAGS = ['-fopenmp'])
 636             env.Append(LIBS = ['gomp'])
 637
 638     # Load tools
 639     env.Tool('lex')
 640     if env['msvc']:
 641         env.Append(LEXFLAGS = [
 642             # Force flex to use const keyword in prototypes, as relies on
 643             # __cplusplus or __STDC__ macro to determine whether it's safe to
 644             # use const keyword, but MSVC never defines __STDC__ unless we
 645             # disable all MSVC extensions.
 646             '-DYY_USE_CONST=',
 647         ])
 648         # Flex relies on __STDC_VERSION__>=199901L to decide when to include
 649         # C99 inttypes.h.  We always have inttypes.h available with MSVC
 650         # (either the one bundled with MSVC 2013, or the one we bundle
 651         # ourselves), but we can't just define __STDC_VERSION__ without
 652         # breaking stuff, as MSVC doesn't fully support C99.  There's also no
 653         # way to premptively include stdint.
 654         env.Append(CCFLAGS = ['-FIinttypes.h'])
 655     if host_platform.system() == 'Windows':
 656         # Prefer winflexbison binaries, as not only they are easier to install
 657         # (no additional dependencies), but also better Windows support.
 658         if check_prog(env, 'win_flex'):
 659             env["LEX"] = 'win_flex'
 660             env.Append(LEXFLAGS = [
 661                 # windows compatibility (uses <io.h> instead of <unistd.h> and
 662                 # _isatty, _fileno functions)
 663                 '--wincompat'
 664             ])
 665
 666     env.Tool('yacc')
 667     if host_platform.system() == 'Windows':
 668         if check_prog(env, 'win_bison'):
 669             env["YACC"] = 'win_bison'
 670
 671     if env['llvm']:
 672         env.Tool('llvm')
 673
 674     # Custom builders and methods
 675     env.Tool('custom')
 676     createInstallMethods(env)
 677     createMSVCCompatMethods(env)
 678
 679     env.PkgCheckModules('X11', ['x11', 'xext', 'xdamage', 'xfixes', 'glproto >= 1.4.13'])
 680     env.PkgCheckModules('XCB', ['x11-xcb', 'xcb-glx >= 1.8.1', 'xcb-dri2 >= 1.8'])
 681     env.PkgCheckModules('XF86VIDMODE', ['xxf86vm'])
 682     env.PkgCheckModules('DRM', ['libdrm >= 2.4.38'])
 683     env.PkgCheckModules('UDEV', ['libudev >= 151'])
 684
 685     if env['x11']:
 686         env.Append(CPPPATH = env['X11_CPPPATH'])
 687
 688     env['dri'] = env['x11'] and env['drm']
 689
 690     # for debugging
 691     #print env.Dump()
 692
 693
 694 def exists(env):
 695     return 1