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