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 msvc2013_compat(env):
  86     if env['gcc']:
  87         env.Append(CCFLAGS = [
  88             '-Werror=vla',
  89             '-Werror=pointer-arith',
  90         ])
  91
  92
  93 def unit_test(env, test_name, program_target, args=None):
  94     env.InstallProgram(program_target)
  95
  96     cmd = [program_target[0].abspath]
  97     if args is not None:
  98         cmd += args
  99     cmd = ' '.join(cmd)
 100
 101     # http://www.scons.org/wiki/UnitTests
 102     action = SCons.Action.Action(cmd, "  Running %s ..." % test_name)
 103     alias = env.Alias(test_name, program_target, action)
 104     env.AlwaysBuild(alias)
 105     env.Depends('check', alias)
 106
 107
 108 def num_jobs():
 109     try:
 110         return int(os.environ['NUMBER_OF_PROCESSORS'])
 111     except (ValueError, KeyError):
 112         pass
 113
 114     try:
 115         return os.sysconf('SC_NPROCESSORS_ONLN')
 116     except (ValueError, OSError, AttributeError):
 117         pass
 118
 119     try:
 120         return int(os.popen2("sysctl -n hw.ncpu")[1].read())
 121     except ValueError:
 122         pass
 123
 124     return 1
 125
 126
 127 def check_cc(env, cc, expr, cpp_opt = '-E'):
 128     # Invoke C-preprocessor to determine whether the specified expression is
 129     # true or not.
 130
 131     sys.stdout.write('Checking for %s ... ' % cc)
 132
 133     source = tempfile.NamedTemporaryFile(suffix='.c', delete=False)
 134     source.write('#if !(%s)\n#error\n#endif\n' % expr)
 135     source.close()
 136
 137     pipe = SCons.Action._subproc(env, [env['CC'], cpp_opt, source.name],
 138                                  stdin = 'devnull',
 139                                  stderr = 'devnull',
 140                                  stdout = 'devnull')
 141     result = pipe.wait() == 0
 142
 143     os.unlink(source.name)
 144
 145     sys.stdout.write(' %s\n' % ['no', 'yes'][int(bool(result))])
 146     return result
 147
 148
 149 def check_prog(env, prog):
 150     """Check whether this program exists."""
 151
 152     sys.stdout.write('Checking for %s ... ' % prog)
 153
 154     result = env.Detect(prog)
 155
 156     sys.stdout.write(' %s\n' % ['no', 'yes'][int(bool(result))])
 157     return result
 158
 159
 160 def generate(env):
 161     """Common environment generation code"""
 162
 163     # Tell tools which machine to compile for
 164     env['TARGET_ARCH'] = env['machine']
 165     env['MSVS_ARCH'] = env['machine']
 166
 167     # Toolchain
 168     platform = env['platform']
 169     env.Tool(env['toolchain'])
 170
 171     # Allow override compiler and specify additional flags from environment
 172     if os.environ.has_key('CC'):
 173         env['CC'] = os.environ['CC']
 174         # Update CCVERSION to match
 175         pipe = SCons.Action._subproc(env, [env['CC'], '--version'],
 176                                      stdin = 'devnull',
 177                                      stderr = 'devnull',
 178                                      stdout = subprocess.PIPE)
 179         if pipe.wait() == 0:
 180             line = pipe.stdout.readline()
 181             match = re.search(r'[0-9]+(\.[0-9]+)+', line)
 182             if match:
 183                 env['CCVERSION'] = match.group(0)
 184     if os.environ.has_key('CFLAGS'):
 185         env['CCFLAGS'] += SCons.Util.CLVar(os.environ['CFLAGS'])
 186     if os.environ.has_key('CXX'):
 187         env['CXX'] = os.environ['CXX']
 188     if os.environ.has_key('CXXFLAGS'):
 189         env['CXXFLAGS'] += SCons.Util.CLVar(os.environ['CXXFLAGS'])
 190     if os.environ.has_key('LDFLAGS'):
 191         env['LINKFLAGS'] += SCons.Util.CLVar(os.environ['LDFLAGS'])
 192
 193     # Detect gcc/clang not by executable name, but through pre-defined macros
 194     # as autoconf does, to avoid drawing wrong conclusions when using tools
 195     # that overrice CC/CXX like scan-build.
 196     env['gcc'] = 0
 197     env['clang'] = 0
 198     env['msvc'] = 0
 199     if host_platform.system() == 'Windows':
 200         env['msvc'] = check_cc(env, 'MSVC', 'defined(_MSC_VER)', '/E')
 201     if not env['msvc']:
 202         env['gcc'] = check_cc(env, 'GCC', 'defined(__GNUC__) && !defined(__clang__)')
 203         env['clang'] = check_cc(env, 'Clang', '__clang__')
 204     env['suncc'] = env['platform'] == 'sunos' and os.path.basename(env['CC']) == 'cc'
 205     env['icc'] = 'icc' == os.path.basename(env['CC'])
 206
 207     if env['msvc'] and env['toolchain'] == 'default' and env['machine'] == 'x86_64':
 208         # MSVC x64 support is broken in earlier versions of scons
 209         env.EnsurePythonVersion(2, 0)
 210
 211     # shortcuts
 212     machine = env['machine']
 213     platform = env['platform']
 214     x86 = env['machine'] == 'x86'
 215     ppc = env['machine'] == 'ppc'
 216     gcc_compat = env['gcc'] or env['clang']
 217     msvc = env['msvc']
 218     suncc = env['suncc']
 219     icc = env['icc']
 220
 221     # Determine whether we are cross compiling; in particular, whether we need
 222     # to compile code generators with a different compiler as the target code.
 223     hosthost_platform = host_platform.system().lower()
 224     if hosthost_platform.startswith('cygwin'):
 225         hosthost_platform = 'cygwin'
 226     host_machine = os.environ.get('PROCESSOR_ARCHITEW6432', os.environ.get('PROCESSOR_ARCHITECTURE', host_platform.machine()))
 227     host_machine = {
 228         'x86': 'x86',
 229         'i386': 'x86',
 230         'i486': 'x86',
 231         'i586': 'x86',
 232         'i686': 'x86',
 233         'ppc' : 'ppc',
 234         'AMD64': 'x86_64',
 235         'x86_64': 'x86_64',
 236     }.get(host_machine, 'generic')
 237     env['crosscompile'] = platform != hosthost_platform
 238     if machine == 'x86_64' and host_machine != 'x86_64':
 239         env['crosscompile'] = True
 240     env['hostonly'] = False
 241
 242     # Backwards compatability with the debug= profile= options
 243     if env['build'] == 'debug':
 244         if not env['debug']:
 245             print 'scons: warning: debug option is deprecated and will be removed eventually; use instead'
 246             print
 247             print ' scons build=release'
 248             print
 249             env['build'] = 'release'
 250         if env['profile']:
 251             print 'scons: warning: profile option is deprecated and will be removed eventually; use instead'
 252             print
 253             print ' scons build=profile'
 254             print
 255             env['build'] = 'profile'
 256     if False:
 257         # Enforce SConscripts to use the new build variable
 258         env.popitem('debug')
 259         env.popitem('profile')
 260     else:
 261         # Backwards portability with older sconscripts
 262         if env['build'] in ('debug', 'checked'):
 263             env['debug'] = True
 264             env['profile'] = False
 265         if env['build'] == 'profile':
 266             env['debug'] = False
 267             env['profile'] = True
 268         if env['build'] == 'release':
 269             env['debug'] = False
 270             env['profile'] = False
 271
 272     # Put build output in a separate dir, which depends on the current
 273     # configuration. See also http://www.scons.org/wiki/AdvancedBuildExample
 274     build_topdir = 'build'
 275     build_subdir = env['platform']
 276     if env['embedded']:
 277         build_subdir =  'embedded-' + build_subdir
 278     if env['machine'] != 'generic':
 279         build_subdir += '-' + env['machine']
 280     if env['build'] != 'release':
 281         build_subdir += '-' +  env['build']
 282     build_dir = os.path.join(build_topdir, build_subdir)
 283     # Place the .sconsign file in the build dir too, to avoid issues with
 284     # different scons versions building the same source file
 285     env['build_dir'] = build_dir
 286     env.SConsignFile(os.path.join(build_dir, '.sconsign'))
 287     if 'SCONS_CACHE_DIR' in os.environ:
 288         print 'scons: Using build cache in %s.' % (os.environ['SCONS_CACHE_DIR'],)
 289         env.CacheDir(os.environ['SCONS_CACHE_DIR'])
 290     env['CONFIGUREDIR'] = os.path.join(build_dir, 'conf')
 291     env['CONFIGURELOG'] = os.path.join(os.path.abspath(build_dir), 'config.log')
 292
 293     # Parallel build
 294     if env.GetOption('num_jobs') <= 1:
 295         env.SetOption('num_jobs', num_jobs())
 296
 297     env.Decider('MD5-timestamp')
 298     env.SetOption('max_drift', 60)
 299
 300     # C preprocessor options
 301     cppdefines = []
 302     cppdefines += ['__STDC_LIMIT_MACROS', '__STDC_CONSTANT_MACROS']
 303     if env['build'] in ('debug', 'checked'):
 304         cppdefines += ['DEBUG']
 305     else:
 306         cppdefines += ['NDEBUG']
 307     if env['build'] == 'profile':
 308         cppdefines += ['PROFILE']
 309     if env['platform'] in ('posix', 'linux', 'freebsd', 'darwin'):
 310         cppdefines += [
 311             '_POSIX_SOURCE',
 312             ('_POSIX_C_SOURCE', '199309L'),
 313             '_SVID_SOURCE',
 314             '_BSD_SOURCE',
 315             '_GNU_SOURCE',
 316             '_DEFAULT_SOURCE',
 317             'HAVE_PTHREAD',
 318             'HAVE_POSIX_MEMALIGN',
 319         ]
 320         if env['platform'] == 'darwin':
 321             cppdefines += [
 322                 '_DARWIN_C_SOURCE',
 323                 'GLX_USE_APPLEGL',
 324                 'GLX_DIRECT_RENDERING',
 325             ]
 326         else:
 327             cppdefines += [
 328                 'GLX_DIRECT_RENDERING',
 329                 'GLX_INDIRECT_RENDERING',
 330             ]
 331         if env['platform'] in ('linux', 'freebsd'):
 332             cppdefines += ['HAVE_ALIAS']
 333         else:
 334             cppdefines += ['GLX_ALIAS_UNSUPPORTED']
 335
 336         if env['platform'] in ('linux', 'darwin'):
 337             cppdefines += ['HAVE_XLOCALE_H']
 338
 339     if env['platform'] == 'haiku':
 340         cppdefines += [
 341             'HAVE_PTHREAD',
 342             'HAVE_POSIX_MEMALIGN'
 343         ]
 344     if platform == 'windows':
 345         cppdefines += [
 346             'WIN32',
 347             '_WINDOWS',
 348             #'_UNICODE',
 349             #'UNICODE',
 350             # http://msdn.microsoft.com/en-us/library/aa383745.aspx
 351             ('_WIN32_WINNT', '0x0601'),
 352             ('WINVER', '0x0601'),
 353         ]
 354         if gcc_compat:
 355             cppdefines += [('__MSVCRT_VERSION__', '0x0700')]
 356         if msvc:
 357             cppdefines += [
 358                 'VC_EXTRALEAN',
 359                 '_USE_MATH_DEFINES',
 360                 '_CRT_SECURE_NO_WARNINGS',
 361                 '_CRT_SECURE_NO_DEPRECATE',
 362                 '_SCL_SECURE_NO_WARNINGS',
 363                 '_SCL_SECURE_NO_DEPRECATE',
 364                 '_ALLOW_KEYWORD_MACROS',
 365                 '_HAS_EXCEPTIONS=0', # Tell C++ STL to not use exceptions
 366             ]
 367         if env['build'] in ('debug', 'checked'):
 368             cppdefines += ['_DEBUG']
 369     if platform == 'windows':
 370         cppdefines += ['PIPE_SUBSYSTEM_WINDOWS_USER']
 371     if env['embedded']:
 372         cppdefines += ['PIPE_SUBSYSTEM_EMBEDDED']
 373     if env['texture_float']:
 374         print 'warning: Floating-point textures enabled.'
 375         print 'warning: Please consult docs/patents.txt with your lawyer before building Mesa.'
 376         cppdefines += ['TEXTURE_FLOAT_ENABLED']
 377     if gcc_compat:
 378         ccversion = env['CCVERSION']
 379         cppdefines += [
 380             'HAVE___BUILTIN_EXPECT',
 381             'HAVE___BUILTIN_FFS',
 382             'HAVE___BUILTIN_FFSLL',
 383             'HAVE_FUNC_ATTRIBUTE_FLATTEN',
 384             'HAVE_FUNC_ATTRIBUTE_UNUSED',
 385             # GCC 3.0
 386             'HAVE_FUNC_ATTRIBUTE_FORMAT',
 387             'HAVE_FUNC_ATTRIBUTE_PACKED',
 388             # GCC 3.4
 389             'HAVE___BUILTIN_CTZ',
 390             'HAVE___BUILTIN_POPCOUNT',
 391             'HAVE___BUILTIN_POPCOUNTLL',
 392             'HAVE___BUILTIN_CLZ',
 393             'HAVE___BUILTIN_CLZLL',
 394         ]
 395         if distutils.version.LooseVersion(ccversion) >= distutils.version.LooseVersion('4.5'):
 396             cppdefines += ['HAVE___BUILTIN_UNREACHABLE']
 397     env.Append(CPPDEFINES = cppdefines)
 398
 399     # C compiler options
 400     cflags = [] # C
 401     cxxflags = [] # C++
 402     ccflags = [] # C & C++
 403     if gcc_compat:
 404         ccversion = env['CCVERSION']
 405         if env['build'] == 'debug':
 406             ccflags += ['-O0']
 407         elif env['gcc'] and ccversion.startswith('4.2.'):
 408             # gcc 4.2.x optimizer is broken
 409             print "warning: gcc 4.2.x optimizer is broken -- disabling optimizations"
 410             ccflags += ['-O0']
 411         else:
 412             ccflags += ['-O3']
 413         if env['gcc']:
 414             # gcc's builtin memcmp is slower than glibc's
 415             # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052
 416             ccflags += ['-fno-builtin-memcmp']
 417         # Work around aliasing bugs - developers should comment this out
 418         ccflags += ['-fno-strict-aliasing']
 419         ccflags += ['-g']
 420         if env['build'] in ('checked', 'profile') or env['asan']:
 421             # See http://code.google.com/p/jrfonseca/wiki/Gprof2Dot#Which_options_should_I_pass_to_gcc_when_compiling_for_profiling?
 422             ccflags += [
 423                 '-fno-omit-frame-pointer',
 424             ]
 425             if env['gcc']:
 426                 ccflags += ['-fno-optimize-sibling-calls']
 427         if env['machine'] == 'x86':
 428             ccflags += [
 429                 '-m32',
 430                 #'-march=pentium4',
 431             ]
 432             if platform != 'haiku':
 433                 # NOTE: We need to ensure stack is realigned given that we
 434                 # produce shared objects, and have no control over the stack
 435                 # alignment policy of the application. Therefore we need
 436                 # -mstackrealign ore -mincoming-stack-boundary=2.
 437                 #
 438                 # XXX: We could have SSE without -mstackrealign if we always used
 439                 # __attribute__((force_align_arg_pointer)), but that's not
 440                 # always the case.
 441                 ccflags += [
 442                     '-mstackrealign', # ensure stack is aligned
 443                     '-msse', '-msse2', # enable SIMD intrinsics
 444                     '-mfpmath=sse', # generate SSE floating-point arithmetic
 445                 ]
 446             if platform in ['windows', 'darwin']:
 447                 # Workaround http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216
 448                 ccflags += ['-fno-common']
 449             if platform in ['haiku']:
 450                 # Make optimizations compatible with Pentium or higher on Haiku
 451                 ccflags += [
 452                     '-mstackrealign', # ensure stack is aligned
 453                     '-march=i586', # Haiku target is Pentium
 454                     '-mtune=i686' # use i686 where we can
 455                 ]
 456         if env['machine'] == 'x86_64':
 457             ccflags += ['-m64']
 458             if platform == 'darwin':
 459                 ccflags += ['-fno-common']
 460         if env['platform'] not in ('cygwin', 'haiku', 'windows'):
 461             ccflags += ['-fvisibility=hidden']
 462         # See also:
 463         # - http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
 464         ccflags += [
 465             '-Wall',
 466             '-Wno-long-long',
 467             '-fmessage-length=0', # be nice to Eclipse
 468         ]
 469         cflags += [
 470             '-Wmissing-prototypes',
 471             '-std=gnu99',
 472         ]
 473     if icc:
 474         cflags += [
 475             '-std=gnu99',
 476         ]
 477     if msvc:
 478         # See also:
 479         # - http://msdn.microsoft.com/en-us/library/19z1t1wy.aspx
 480         # - cl /?
 481         if env['build'] == 'debug':
 482             ccflags += [
 483               '/Od', # disable optimizations
 484               '/Oi', # enable intrinsic functions
 485             ]
 486         else:
 487             ccflags += [
 488                 '/O2', # optimize for speed
 489             ]
 490         if env['build'] == 'release':
 491             ccflags += [
 492                 '/GL', # enable whole program optimization
 493             ]
 494         else:
 495             ccflags += [
 496                 '/Oy-', # disable frame pointer omission
 497                 '/GL-', # disable whole program optimization
 498             ]
 499         ccflags += [
 500             '/W3', # warning level
 501             '/wd4018', # signed/unsigned mismatch
 502             '/wd4056', # overflow in floating-point constant arithmetic
 503             '/wd4244', # conversion from 'type1' to 'type2', possible loss of data
 504             '/wd4267', # 'var' : conversion from 'size_t' to 'type', possible loss of data
 505             '/wd4305', # truncation from 'type1' to 'type2'
 506             '/wd4351', # new behavior: elements of array 'array' will be default initialized
 507             '/wd4756', # overflow in constant arithmetic
 508             '/wd4800', # forcing value to bool 'true' or 'false' (performance warning)
 509             '/wd4996', # disable deprecated POSIX name warnings
 510         ]
 511         if env['machine'] == 'x86':
 512             ccflags += [
 513                 '/arch:SSE2', # use the SSE2 instructions (default since MSVC 2012)
 514             ]
 515         if platform == 'windows':
 516             ccflags += [
 517                 # TODO
 518             ]
 519         # Automatic pdb generation
 520         # See http://scons.tigris.org/issues/show_bug.cgi?id=1656
 521         env.EnsureSConsVersion(0, 98, 0)
 522         env['PDB'] = '${TARGET.base}.pdb'
 523     env.Append(CCFLAGS = ccflags)
 524     env.Append(CFLAGS = cflags)
 525     env.Append(CXXFLAGS = cxxflags)
 526
 527     if env['platform'] == 'windows' and msvc:
 528         # Choose the appropriate MSVC CRT
 529         # http://msdn.microsoft.com/en-us/library/2kzt1wy3.aspx
 530         if env['build'] in ('debug', 'checked'):
 531             env.Append(CCFLAGS = ['/MTd'])
 532             env.Append(SHCCFLAGS = ['/LDd'])
 533         else:
 534             env.Append(CCFLAGS = ['/MT'])
 535             env.Append(SHCCFLAGS = ['/LD'])
 536
 537     # Static code analysis
 538     if env['analyze']:
 539         if env['msvc']:
 540             # http://msdn.microsoft.com/en-us/library/ms173498.aspx
 541             env.Append(CCFLAGS = [
 542                 '/analyze',
 543                 #'/analyze:log', '${TARGET.base}.xml',
 544                 '/wd28251', # Inconsistent annotation for function
 545             ])
 546         if env['clang']:
 547             # scan-build will produce more comprehensive output
 548             env.Append(CCFLAGS = ['--analyze'])
 549
 550     # https://github.com/google/sanitizers/wiki/AddressSanitizer
 551     if env['asan']:
 552         if gcc_compat:
 553             env.Append(CCFLAGS = [
 554                 '-fsanitize=address',
 555             ])
 556             env.Append(LINKFLAGS = [
 557                 '-fsanitize=address',
 558             ])
 559
 560     # Assembler options
 561     if gcc_compat:
 562         if env['machine'] == 'x86':
 563             env.Append(ASFLAGS = ['-m32'])
 564         if env['machine'] == 'x86_64':
 565             env.Append(ASFLAGS = ['-m64'])
 566
 567     # Linker options
 568     linkflags = []
 569     shlinkflags = []
 570     if gcc_compat:
 571         if env['machine'] == 'x86':
 572             linkflags += ['-m32']
 573         if env['machine'] == 'x86_64':
 574             linkflags += ['-m64']
 575         if env['platform'] not in ('darwin'):
 576             shlinkflags += [
 577                 '-Wl,-Bsymbolic',
 578             ]
 579         # Handle circular dependencies in the libraries
 580         if env['platform'] in ('darwin'):
 581             pass
 582         else:
 583             env['_LIBFLAGS'] = '-Wl,--start-group ' + env['_LIBFLAGS'] + ' -Wl,--end-group'
 584         if env['platform'] == 'windows':
 585             linkflags += [
 586                 '-Wl,--nxcompat', # DEP
 587                 '-Wl,--dynamicbase', # ASLR
 588             ]
 589             # Avoid depending on gcc runtime DLLs
 590             linkflags += ['-static-libgcc']
 591             if 'w64' in env['CC'].split('-'):
 592                 linkflags += ['-static-libstdc++']
 593             # Handle the @xx symbol munging of DLL exports
 594             shlinkflags += ['-Wl,--enable-stdcall-fixup']
 595             #shlinkflags += ['-Wl,--kill-at']
 596     if msvc:
 597         if env['build'] == 'release':
 598             # enable Link-time Code Generation
 599             linkflags += ['/LTCG']
 600             env.Append(ARFLAGS = ['/LTCG'])
 601     if platform == 'windows' and msvc:
 602         # See also:
 603         # - http://msdn2.microsoft.com/en-us/library/y0zzbyt4.aspx
 604         linkflags += [
 605             '/fixed:no',
 606             '/incremental:no',
 607             '/dynamicbase', # ASLR
 608             '/nxcompat', # DEP
 609         ]
 610     env.Append(LINKFLAGS = linkflags)
 611     env.Append(SHLINKFLAGS = shlinkflags)
 612
 613     # We have C++ in several libraries, so always link with the C++ compiler
 614     if gcc_compat:
 615         env['LINK'] = env['CXX']
 616
 617     # Default libs
 618     libs = []
 619     if env['platform'] in ('darwin', 'freebsd', 'linux', 'posix', 'sunos'):
 620         libs += ['m', 'pthread', 'dl']
 621     if env['platform'] in ('linux',):
 622         libs += ['rt']
 623     if env['platform'] in ('haiku'):
 624         libs += ['root', 'be', 'network', 'translation']
 625     env.Append(LIBS = libs)
 626
 627     # OpenMP
 628     if env['openmp']:
 629         if env['msvc']:
 630             env.Append(CCFLAGS = ['/openmp'])
 631             # When building openmp release VS2008 link.exe crashes with LNK1103 error.
 632             # Workaround: overwrite PDB flags with empty value as it isn't required anyways
 633             if env['build'] == 'release':
 634                 env['PDB'] = ''
 635         if env['gcc']:
 636             env.Append(CCFLAGS = ['-fopenmp'])
 637             env.Append(LIBS = ['gomp'])
 638
 639     # Load tools
 640     env.Tool('lex')
 641     if env['msvc']:
 642         env.Append(LEXFLAGS = [
 643             # Force flex to use const keyword in prototypes, as relies on
 644             # __cplusplus or __STDC__ macro to determine whether it's safe to
 645             # use const keyword, but MSVC never defines __STDC__ unless we
 646             # disable all MSVC extensions.
 647             '-DYY_USE_CONST=',
 648         ])
 649         # Flex relies on __STDC_VERSION__>=199901L to decide when to include
 650         # C99 inttypes.h.  We always have inttypes.h available with MSVC
 651         # (either the one bundled with MSVC 2013, or the one we bundle
 652         # ourselves), but we can't just define __STDC_VERSION__ without
 653         # breaking stuff, as MSVC doesn't fully support C99.  There's also no
 654         # way to premptively include stdint.
 655         env.Append(CCFLAGS = ['-FIinttypes.h'])
 656     if host_platform.system() == 'Windows':
 657         # Prefer winflexbison binaries, as not only they are easier to install
 658         # (no additional dependencies), but also better Windows support.
 659         if check_prog(env, 'win_flex'):
 660             env["LEX"] = 'win_flex'
 661             env.Append(LEXFLAGS = [
 662                 # windows compatibility (uses <io.h> instead of <unistd.h> and
 663                 # _isatty, _fileno functions)
 664                 '--wincompat'
 665             ])
 666
 667     env.Tool('yacc')
 668     if host_platform.system() == 'Windows':
 669         if check_prog(env, 'win_bison'):
 670             env["YACC"] = 'win_bison'
 671
 672     if env['llvm']:
 673         env.Tool('llvm')
 674
 675     # Custom builders and methods
 676     env.Tool('custom')
 677     env.AddMethod(install_program, 'InstallProgram')
 678     env.AddMethod(install_shared_library, 'InstallSharedLibrary')
 679     env.AddMethod(msvc2013_compat, 'MSVC2013Compat')
 680     env.AddMethod(unit_test, 'UnitTest')
 681
 682     env.PkgCheckModules('X11', ['x11', 'xext', 'xdamage', 'xfixes', 'glproto >= 1.4.13'])
 683     env.PkgCheckModules('XCB', ['x11-xcb', 'xcb-glx >= 1.8.1', 'xcb-dri2 >= 1.8'])
 684     env.PkgCheckModules('XF86VIDMODE', ['xxf86vm'])
 685     env.PkgCheckModules('DRM', ['libdrm >= 2.4.38'])
 686     env.PkgCheckModules('UDEV', ['libudev >= 151'])
 687
 688     if env['x11']:
 689         env.Append(CPPPATH = env['X11_CPPPATH'])
 690
 691     env['dri'] = env['x11'] and env['drm']
 692
 693     # for debugging
 694     #print env.Dump()
 695
 696
 697 def exists(env):
 698     return 1