SConstruct

   1 # -*- mode:python -*-
   2
   3 # Copyright (c) 2004-2005 The Regents of The University of Michigan
   4 # All rights reserved.
   5 #
   6 # Redistribution and use in source and binary forms, with or without
   7 # modification, are permitted provided that the following conditions are
   8 # met: redistributions of source code must retain the above copyright
   9 # notice, this list of conditions and the following disclaimer;
  10 # redistributions in binary form must reproduce the above copyright
  11 # notice, this list of conditions and the following disclaimer in the
  12 # documentation and/or other materials provided with the distribution;
  13 # neither the name of the copyright holders nor the names of its
  14 # contributors may be used to endorse or promote products derived from
  15 # this software without specific prior written permission.
  16 #
  17 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28 #
  29 # Authors: Steve Reinhardt
  30
  31 ###################################################
  32 #
  33 # SCons top-level build description (SConstruct) file.
  34 #
  35 # While in this directory ('m5'), just type 'scons' to build the default
  36 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
  37 # to build some other configuration (e.g., 'build/ALPHA_FS/m5.opt' for
  38 # the optimized full-system version).
  39 #
  40 # You can build M5 in a different directory as long as there is a
  41 # 'build/<CONFIG>' somewhere along the target path.  The build system
  42 # expects that all configs under the same build directory are being
  43 # built for the same host system.
  44 #
  45 # Examples:
  46 #
  47 #   The following two commands are equivalent.  The '-u' option tells
  48 #   scons to search up the directory tree for this SConstruct file.
  49 #   % cd <path-to-src>/m5 ; scons build/ALPHA_FS/m5.debug
  50 #   % cd <path-to-src>/m5/build/ALPHA_FS; scons -u m5.debug
  51 #
  52 #   The following two commands are equivalent and demonstrate building
  53 #   in a directory outside of the source tree.  The '-C' option tells
  54 #   scons to chdir to the specified directory to find this SConstruct
  55 #   file.
  56 #   % cd <path-to-src>/m5 ; scons /local/foo/build/ALPHA_FS/m5.debug
  57 #   % cd /local/foo/build/ALPHA_FS; scons -C <path-to-src>/m5 m5.debug
  58 #
  59 # You can use 'scons -H' to print scons options.  If you're in this
  60 # 'm5' directory (or use -u or -C to tell scons where to find this
  61 # file), you can use 'scons -h' to print all the M5-specific build
  62 # options as well.
  63 #
  64 ###################################################
  65
  66 import sys
  67 import os
  68 import subprocess
  69
  70 from os.path import join as joinpath
  71
  72 # Check for recent-enough Python and SCons versions.  If your system's
  73 # default installation of Python is not recent enough, you can use a
  74 # non-default installation of the Python interpreter by either (1)
  75 # rearranging your PATH so that scons finds the non-default 'python'
  76 # first or (2) explicitly invoking an alternative interpreter on the
  77 # scons script, e.g., "/usr/local/bin/python2.4 `which scons` [args]".
  78 EnsurePythonVersion(2,4)
  79
  80 # Ironically, SCons 0.96 dies if you give EnsureSconsVersion a
  81 # 3-element version number.
  82 min_scons_version = (0,96,91)
  83 try:
  84     EnsureSConsVersion(*min_scons_version)
  85 except:
  86     print "Error checking current SCons version."
  87     print "SCons", ".".join(map(str,min_scons_version)), "or greater required."
  88     Exit(2)
  89
  90
  91 # The absolute path to the current directory (where this file lives).
  92 ROOT = Dir('.').abspath
  93
  94 # Path to the M5 source tree.
  95 SRCDIR = joinpath(ROOT, 'src')
  96
  97 # tell python where to find m5 python code
  98 sys.path.append(joinpath(ROOT, 'src/python'))
  99
 100 ###################################################
 101 #
 102 # Figure out which configurations to set up based on the path(s) of
 103 # the target(s).
 104 #
 105 ###################################################
 106
 107 # Find default configuration & binary.
 108 Default(os.environ.get('M5_DEFAULT_BINARY', 'build/ALPHA_SE/m5.debug'))
 109
 110 # helper function: find last occurrence of element in list
 111 def rfind(l, elt, offs = -1):
 112     for i in range(len(l)+offs, 0, -1):
 113         if l[i] == elt:
 114             return i
 115     raise ValueError, "element not found"
 116
 117 # helper function: compare dotted version numbers.
 118 # E.g., compare_version('1.3.25', '1.4.1')
 119 # returns -1, 0, 1 if v1 is <, ==, > v2
 120 def compare_versions(v1, v2):
 121     # Convert dotted strings to lists
 122     v1 = map(int, v1.split('.'))
 123     v2 = map(int, v2.split('.'))
 124     # Compare corresponding elements of lists
 125     for n1,n2 in zip(v1, v2):
 126         if n1 < n2: return -1
 127         if n1 > n2: return  1
 128     # all corresponding values are equal... see if one has extra values
 129     if len(v1) < len(v2): return -1
 130     if len(v1) > len(v2): return  1
 131     return 0
 132
 133 # Each target must have 'build' in the interior of the path; the
 134 # directory below this will determine the build parameters.  For
 135 # example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
 136 # recognize that ALPHA_SE specifies the configuration because it
 137 # follow 'build' in the bulid path.
 138
 139 # Generate absolute paths to targets so we can see where the build dir is
 140 if COMMAND_LINE_TARGETS:
 141     # Ask SCons which directory it was invoked from
 142     launch_dir = GetLaunchDir()
 143     # Make targets relative to invocation directory
 144     abs_targets = map(lambda x: os.path.normpath(joinpath(launch_dir, str(x))),
 145                       COMMAND_LINE_TARGETS)
 146 else:
 147     # Default targets are relative to root of tree
 148     abs_targets = map(lambda x: os.path.normpath(joinpath(ROOT, str(x))),
 149                       DEFAULT_TARGETS)
 150
 151
 152 # Generate a list of the unique build roots and configs that the
 153 # collected targets reference.
 154 build_paths = []
 155 build_root = None
 156 for t in abs_targets:
 157     path_dirs = t.split('/')
 158     try:
 159         build_top = rfind(path_dirs, 'build', -2)
 160     except:
 161         print "Error: no non-leaf 'build' dir found on target path", t
 162         Exit(1)
 163     this_build_root = joinpath('/',*path_dirs[:build_top+1])
 164     if not build_root:
 165         build_root = this_build_root
 166     else:
 167         if this_build_root != build_root:
 168             print "Error: build targets not under same build root\n"\
 169                   "  %s\n  %s" % (build_root, this_build_root)
 170             Exit(1)
 171     build_path = joinpath('/',*path_dirs[:build_top+2])
 172     if build_path not in build_paths:
 173         build_paths.append(build_path)
 174
 175 ###################################################
 176 #
 177 # Set up the default build environment.  This environment is copied
 178 # and modified according to each selected configuration.
 179 #
 180 ###################################################
 181
 182 env = Environment(ENV = os.environ,  # inherit user's environment vars
 183                   ROOT = ROOT,
 184                   SRCDIR = SRCDIR)
 185 Export('env')
 186
 187 #Parse CC/CXX early so that we use the correct compiler for
 188 # to test for dependencies/versions/libraries/includes
 189 if ARGUMENTS.get('CC', None):
 190     env['CC'] = ARGUMENTS.get('CC')
 191
 192 if ARGUMENTS.get('CXX', None):
 193     env['CXX'] = ARGUMENTS.get('CXX')
 194
 195 env.SConsignFile(joinpath(build_root,"sconsign"))
 196
 197 # Default duplicate option is to use hard links, but this messes up
 198 # when you use emacs to edit a file in the target dir, as emacs moves
 199 # file to file~ then copies to file, breaking the link.  Symbolic
 200 # (soft) links work better.
 201 env.SetOption('duplicate', 'soft-copy')
 202
 203 # I waffle on this setting... it does avoid a few painful but
 204 # unnecessary builds, but it also seems to make trivial builds take
 205 # noticeably longer.
 206 if False:
 207     env.TargetSignatures('content')
 208
 209 # M5_PLY is used by isa_parser.py to find the PLY package.
 210 env.Append(ENV = { 'M5_PLY' : Dir('ext/ply') })
 211 env['GCC'] = False
 212 env['SUNCC'] = False
 213 env['ICC'] = False
 214 env['GCC'] = subprocess.Popen(env['CXX'] + ' --version', shell=True,
 215         stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
 216         close_fds=True).communicate()[0].find('GCC') >= 0
 217 env['SUNCC'] = subprocess.Popen(env['CXX'] + ' -V', shell=True,
 218         stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
 219         close_fds=True).communicate()[0].find('Sun C++') >= 0
 220 env['ICC'] = subprocess.Popen(env['CXX'] + ' -V', shell=True,
 221         stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
 222         close_fds=True).communicate()[0].find('Intel') >= 0
 223 if env['GCC'] + env['SUNCC'] + env['ICC'] > 1:
 224     print 'Error: How can we have two at the same time?'
 225     Exit(1)
 226
 227
 228 # Set up default C++ compiler flags
 229 if env['GCC']:
 230     env.Append(CCFLAGS='-pipe')
 231     env.Append(CCFLAGS='-fno-strict-aliasing')
 232     env.Append(CCFLAGS=Split('-Wall -Wno-sign-compare -Werror -Wundef'))
 233 elif env['ICC']:
 234     pass #Fix me... add warning flags once we clean up icc warnings
 235 elif env['SUNCC']:
 236     env.Append(CCFLAGS='-Qoption ccfe')
 237     env.Append(CCFLAGS='-features=gcc')
 238     env.Append(CCFLAGS='-features=extensions')
 239     env.Append(CCFLAGS='-library=stlport4')
 240     env.Append(CCFLAGS='-xar')
 241 #    env.Append(CCFLAGS='-instances=semiexplicit')
 242 else:
 243     print 'Error: Don\'t know what compiler options to use for your compiler.'
 244     print '       Please fix SConstruct and src/SConscript and try again.'
 245     Exit(1)
 246
 247 if sys.platform == 'cygwin':
 248     # cygwin has some header file issues...
 249     env.Append(CCFLAGS=Split("-Wno-uninitialized"))
 250 env.Append(CPPPATH=[Dir('ext/dnet')])
 251
 252 # Check for SWIG
 253 if not env.has_key('SWIG'):
 254     print 'Error: SWIG utility not found.'
 255     print '       Please install (see http://www.swig.org) and retry.'
 256     Exit(1)
 257
 258 # Check for appropriate SWIG version
 259 swig_version = os.popen('swig -version').read().split()
 260 # First 3 words should be "SWIG Version x.y.z"
 261 if swig_version[0] != 'SWIG' or swig_version[1] != 'Version':
 262     print 'Error determining SWIG version.'
 263     Exit(1)
 264
 265 min_swig_version = '1.3.28'
 266 if compare_versions(swig_version[2], min_swig_version) < 0:
 267     print 'Error: SWIG version', min_swig_version, 'or newer required.'
 268     print '       Installed version:', swig_version[2]
 269     Exit(1)
 270
 271 # Set up SWIG flags & scanner
 272 env.Append(SWIGFLAGS=Split('-c++ -python -modern $_CPPINCFLAGS'))
 273
 274 import SCons.Scanner
 275
 276 swig_inc_re = '^[ \t]*[%,#][ \t]*(?:include|import)[ \t]*(<|")([^>"]+)(>|")'
 277
 278 swig_scanner = SCons.Scanner.ClassicCPP("SwigScan", ".i", "CPPPATH",
 279                                         swig_inc_re)
 280
 281 env.Append(SCANNERS = swig_scanner)
 282
 283 # Platform-specific configuration.  Note again that we assume that all
 284 # builds under a given build root run on the same host platform.
 285 conf = Configure(env,
 286                  conf_dir = joinpath(build_root, '.scons_config'),
 287                  log_file = joinpath(build_root, 'scons_config.log'))
 288
 289 # Find Python include and library directories for embedding the
 290 # interpreter.  For consistency, we will use the same Python
 291 # installation used to run scons (and thus this script).  If you want
 292 # to link in an alternate version, see above for instructions on how
 293 # to invoke scons with a different copy of the Python interpreter.
 294
 295 # Get brief Python version name (e.g., "python2.4") for locating
 296 # include & library files
 297 py_version_name = 'python' + sys.version[:3]
 298
 299 # include path, e.g. /usr/local/include/python2.4
 300 py_header_path = joinpath(sys.exec_prefix, 'include', py_version_name)
 301 env.Append(CPPPATH = py_header_path)
 302 # verify that it works
 303 if not conf.CheckHeader('Python.h', '<>'):
 304     print "Error: can't find Python.h header in", py_header_path
 305     Exit(1)
 306
 307 # add library path too if it's not in the default place
 308 py_lib_path = None
 309 if sys.exec_prefix != '/usr':
 310     py_lib_path = joinpath(sys.exec_prefix, 'lib')
 311 elif sys.platform == 'cygwin':
 312     # cygwin puts the .dll in /bin for some reason
 313     py_lib_path = '/bin'
 314 if py_lib_path:
 315     env.Append(LIBPATH = py_lib_path)
 316     print 'Adding', py_lib_path, 'to LIBPATH for', py_version_name
 317 if not conf.CheckLib(py_version_name):
 318     print "Error: can't find Python library", py_version_name
 319     Exit(1)
 320
 321 # On Solaris you need to use libsocket for socket ops
 322 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 323    if not conf.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
 324        print "Can't find library with socket calls (e.g. accept())"
 325        Exit(1)
 326
 327 # Check for zlib.  If the check passes, libz will be automatically
 328 # added to the LIBS environment variable.
 329 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
 330     print 'Error: did not find needed zlib compression library '\
 331           'and/or zlib.h header file.'
 332     print '       Please install zlib and try again.'
 333     Exit(1)
 334
 335 # Check for <fenv.h> (C99 FP environment control)
 336 have_fenv = conf.CheckHeader('fenv.h', '<>')
 337 if not have_fenv:
 338     print "Warning: Header file <fenv.h> not found."
 339     print "         This host has no IEEE FP rounding mode control."
 340
 341 # Check for mysql.
 342 mysql_config = WhereIs('mysql_config')
 343 have_mysql = mysql_config != None
 344
 345 # Check MySQL version.
 346 if have_mysql:
 347     mysql_version = os.popen(mysql_config + ' --version').read()
 348     min_mysql_version = '4.1'
 349     if compare_versions(mysql_version, min_mysql_version) < 0:
 350         print 'Warning: MySQL', min_mysql_version, 'or newer required.'
 351         print '         Version', mysql_version, 'detected.'
 352         have_mysql = False
 353
 354 # Set up mysql_config commands.
 355 if have_mysql:
 356     mysql_config_include = mysql_config + ' --include'
 357     if os.system(mysql_config_include + ' > /dev/null') != 0:
 358         # older mysql_config versions don't support --include, use
 359         # --cflags instead
 360         mysql_config_include = mysql_config + ' --cflags | sed s/\\\'//g'
 361     # This seems to work in all versions
 362     mysql_config_libs = mysql_config + ' --libs'
 363
 364 env = conf.Finish()
 365
 366 # Define the universe of supported ISAs
 367 all_isa_list = [ ]
 368 Export('all_isa_list')
 369
 370 # Define the universe of supported CPU models
 371 all_cpu_list = [ ]
 372 default_cpus = [ ]
 373 Export('all_cpu_list', 'default_cpus')
 374
 375 # Sticky options get saved in the options file so they persist from
 376 # one invocation to the next (unless overridden, in which case the new
 377 # value becomes sticky).
 378 sticky_opts = Options(args=ARGUMENTS)
 379 Export('sticky_opts')
 380
 381 # Non-sticky options only apply to the current build.
 382 nonsticky_opts = Options(args=ARGUMENTS)
 383 Export('nonsticky_opts')
 384
 385 # Walk the tree and execute all SConsopts scripts that wil add to the
 386 # above options
 387 for root, dirs, files in os.walk('.'):
 388     if 'SConsopts' in files:
 389         SConscript(os.path.join(root, 'SConsopts'))
 390
 391 all_isa_list.sort()
 392 all_cpu_list.sort()
 393 default_cpus.sort()
 394
 395 sticky_opts.AddOptions(
 396     EnumOption('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
 397     BoolOption('FULL_SYSTEM', 'Full-system support', False),
 398     # There's a bug in scons 0.96.1 that causes ListOptions with list
 399     # values (more than one value) not to be able to be restored from
 400     # a saved option file.  If this causes trouble then upgrade to
 401     # scons 0.96.90 or later.
 402     ListOption('CPU_MODELS', 'CPU models', default_cpus, all_cpu_list),
 403     BoolOption('NO_FAST_ALLOC', 'Disable fast object allocator', False),
 404     BoolOption('EFENCE', 'Link with Electric Fence malloc debugger',
 405                False),
 406     BoolOption('SS_COMPATIBLE_FP',
 407                'Make floating-point results compatible with SimpleScalar',
 408                False),
 409     BoolOption('USE_SSE2',
 410                'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
 411                False),
 412     BoolOption('USE_MYSQL', 'Use MySQL for stats output', have_mysql),
 413     BoolOption('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
 414     BoolOption('USE_CHECKER', 'Use checker for detailed CPU models', False),
 415     ('CC', 'C compiler', os.environ.get('CC', env['CC'])),
 416     ('CXX', 'C++ compiler', os.environ.get('CXX', env['CXX'])),
 417     BoolOption('BATCH', 'Use batch pool for build and tests', False),
 418     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
 419     ('PYTHONHOME',
 420      'Override the default PYTHONHOME for this system (use with caution)',
 421      '%s:%s' % (sys.prefix, sys.exec_prefix))
 422     )
 423
 424 nonsticky_opts.AddOptions(
 425     BoolOption('update_ref', 'Update test reference outputs', False)
 426     )
 427
 428 # These options get exported to #defines in config/*.hh (see src/SConscript).
 429 env.ExportOptions = ['FULL_SYSTEM', 'ALPHA_TLASER', 'USE_FENV', \
 430                      'USE_MYSQL', 'NO_FAST_ALLOC', 'SS_COMPATIBLE_FP', \
 431                      'USE_CHECKER', 'PYTHONHOME', 'TARGET_ISA']
 432
 433 # Define a handy 'no-op' action
 434 def no_action(target, source, env):
 435     return 0
 436
 437 env.NoAction = Action(no_action, None)
 438
 439 ###################################################
 440 #
 441 # Define a SCons builder for configuration flag headers.
 442 #
 443 ###################################################
 444
 445 # This function generates a config header file that #defines the
 446 # option symbol to the current option setting (0 or 1).  The source
 447 # operands are the name of the option and a Value node containing the
 448 # value of the option.
 449 def build_config_file(target, source, env):
 450     (option, value) = [s.get_contents() for s in source]
 451     f = file(str(target[0]), 'w')
 452     print >> f, '#define', option, value
 453     f.close()
 454     return None
 455
 456 # Generate the message to be printed when building the config file.
 457 def build_config_file_string(target, source, env):
 458     (option, value) = [s.get_contents() for s in source]
 459     return "Defining %s as %s in %s." % (option, value, target[0])
 460
 461 # Combine the two functions into a scons Action object.
 462 config_action = Action(build_config_file, build_config_file_string)
 463
 464 # The emitter munges the source & target node lists to reflect what
 465 # we're really doing.
 466 def config_emitter(target, source, env):
 467     # extract option name from Builder arg
 468     option = str(target[0])
 469     # True target is config header file
 470     target = joinpath('config', option.lower() + '.hh')
 471     val = env[option]
 472     if isinstance(val, bool):
 473         # Force value to 0/1
 474         val = int(val)
 475     elif isinstance(val, str):
 476         val = '"' + val + '"'
 477
 478     # Sources are option name & value (packaged in SCons Value nodes)
 479     return ([target], [Value(option), Value(val)])
 480
 481 config_builder = Builder(emitter = config_emitter, action = config_action)
 482
 483 env.Append(BUILDERS = { 'ConfigFile' : config_builder })
 484
 485 ###################################################
 486 #
 487 # Define a SCons builder for copying files.  This is used by the
 488 # Python zipfile code in src/python/SConscript, but is placed up here
 489 # since it's potentially more generally applicable.
 490 #
 491 ###################################################
 492
 493 copy_builder = Builder(action = Copy("$TARGET", "$SOURCE"))
 494
 495 env.Append(BUILDERS = { 'CopyFile' : copy_builder })
 496
 497 ###################################################
 498 #
 499 # Define a simple SCons builder to concatenate files.
 500 #
 501 # Used to append the Python zip archive to the executable.
 502 #
 503 ###################################################
 504
 505 concat_builder = Builder(action = Action(['cat $SOURCES > $TARGET',
 506                                           'chmod +x $TARGET']))
 507
 508 env.Append(BUILDERS = { 'Concat' : concat_builder })
 509
 510
 511 # base help text
 512 help_text = '''
 513 Usage: scons [scons options] [build options] [target(s)]
 514
 515 '''
 516
 517 # libelf build is shared across all configs in the build root.
 518 env.SConscript('ext/libelf/SConscript',
 519                build_dir = joinpath(build_root, 'libelf'),
 520                exports = 'env')
 521
 522 ###################################################
 523 #
 524 # This function is used to set up a directory with switching headers
 525 #
 526 ###################################################
 527
 528 env['ALL_ISA_LIST'] = all_isa_list
 529 def make_switching_dir(dirname, switch_headers, env):
 530     # Generate the header.  target[0] is the full path of the output
 531     # header to generate.  'source' is a dummy variable, since we get the
 532     # list of ISAs from env['ALL_ISA_LIST'].
 533     def gen_switch_hdr(target, source, env):
 534         fname = str(target[0])
 535         basename = os.path.basename(fname)
 536         f = open(fname, 'w')
 537         f.write('#include "arch/isa_specific.hh"\n')
 538         cond = '#if'
 539         for isa in all_isa_list:
 540             f.write('%s THE_ISA == %s_ISA\n#include "%s/%s/%s"\n'
 541                     % (cond, isa.upper(), dirname, isa, basename))
 542             cond = '#elif'
 543         f.write('#else\n#error "THE_ISA not set"\n#endif\n')
 544         f.close()
 545         return 0
 546
 547     # String to print when generating header
 548     def gen_switch_hdr_string(target, source, env):
 549         return "Generating switch header " + str(target[0])
 550
 551     # Build SCons Action object. 'varlist' specifies env vars that this
 552     # action depends on; when env['ALL_ISA_LIST'] changes these actions
 553     # should get re-executed.
 554     switch_hdr_action = Action(gen_switch_hdr, gen_switch_hdr_string,
 555                                varlist=['ALL_ISA_LIST'])
 556
 557     # Instantiate actions for each header
 558     for hdr in switch_headers:
 559         env.Command(hdr, [], switch_hdr_action)
 560 Export('make_switching_dir')
 561
 562 ###################################################
 563 #
 564 # Define build environments for selected configurations.
 565 #
 566 ###################################################
 567
 568 # rename base env
 569 base_env = env
 570
 571 for build_path in build_paths:
 572     print "Building in", build_path
 573     # build_dir is the tail component of build path, and is used to
 574     # determine the build parameters (e.g., 'ALPHA_SE')
 575     (build_root, build_dir) = os.path.split(build_path)
 576     # Make a copy of the build-root environment to use for this config.
 577     env = base_env.Copy()
 578
 579     # Set env options according to the build directory config.
 580     sticky_opts.files = []
 581     # Options for $BUILD_ROOT/$BUILD_DIR are stored in
 582     # $BUILD_ROOT/options/$BUILD_DIR so you can nuke
 583     # $BUILD_ROOT/$BUILD_DIR without losing your options settings.
 584     current_opts_file = joinpath(build_root, 'options', build_dir)
 585     if os.path.isfile(current_opts_file):
 586         sticky_opts.files.append(current_opts_file)
 587         print "Using saved options file %s" % current_opts_file
 588     else:
 589         # Build dir-specific options file doesn't exist.
 590
 591         # Make sure the directory is there so we can create it later
 592         opt_dir = os.path.dirname(current_opts_file)
 593         if not os.path.isdir(opt_dir):
 594             os.mkdir(opt_dir)
 595
 596         # Get default build options from source tree.  Options are
 597         # normally determined by name of $BUILD_DIR, but can be
 598         # overriden by 'default=' arg on command line.
 599         default_opts_file = joinpath('build_opts',
 600                                      ARGUMENTS.get('default', build_dir))
 601         if os.path.isfile(default_opts_file):
 602             sticky_opts.files.append(default_opts_file)
 603             print "Options file %s not found,\n  using defaults in %s" \
 604                   % (current_opts_file, default_opts_file)
 605         else:
 606             print "Error: cannot find options file %s or %s" \
 607                   % (current_opts_file, default_opts_file)
 608             Exit(1)
 609
 610     # Apply current option settings to env
 611     sticky_opts.Update(env)
 612     nonsticky_opts.Update(env)
 613
 614     help_text += "Sticky options for %s:\n" % build_dir \
 615                  + sticky_opts.GenerateHelpText(env) \
 616                  + "\nNon-sticky options for %s:\n" % build_dir \
 617                  + nonsticky_opts.GenerateHelpText(env)
 618
 619     # Process option settings.
 620
 621     if not have_fenv and env['USE_FENV']:
 622         print "Warning: <fenv.h> not available; " \
 623               "forcing USE_FENV to False in", build_dir + "."
 624         env['USE_FENV'] = False
 625
 626     if not env['USE_FENV']:
 627         print "Warning: No IEEE FP rounding mode control in", build_dir + "."
 628         print "         FP results may deviate slightly from other platforms."
 629
 630     if env['EFENCE']:
 631         env.Append(LIBS=['efence'])
 632
 633     if env['USE_MYSQL']:
 634         if not have_mysql:
 635             print "Warning: MySQL not available; " \
 636                   "forcing USE_MYSQL to False in", build_dir + "."
 637             env['USE_MYSQL'] = False
 638         else:
 639             print "Compiling in", build_dir, "with MySQL support."
 640             env.ParseConfig(mysql_config_libs)
 641             env.ParseConfig(mysql_config_include)
 642
 643     # Save sticky option settings back to current options file
 644     sticky_opts.Save(current_opts_file, env)
 645
 646     # Do this after we save setting back, or else we'll tack on an
 647     # extra 'qdo' every time we run scons.
 648     if env['BATCH']:
 649         env['CC']  = env['BATCH_CMD'] + ' ' + env['CC']
 650         env['CXX'] = env['BATCH_CMD'] + ' ' + env['CXX']
 651
 652     if env['USE_SSE2']:
 653         env.Append(CCFLAGS='-msse2')
 654
 655     # The src/SConscript file sets up the build rules in 'env' according
 656     # to the configured options.  It returns a list of environments,
 657     # one for each variant build (debug, opt, etc.)
 658     envList = SConscript('src/SConscript', build_dir = build_path,
 659                          exports = 'env')
 660
 661     # Set up the regression tests for each build.
 662     for e in envList:
 663         SConscript('tests/SConscript',
 664                    build_dir = joinpath(build_path, 'tests', e.Label),
 665                    exports = { 'env' : e }, duplicate = False)
 666
 667 Help(help_text)
 668
 669
 670 ###################################################
 671 #
 672 # Let SCons do its thing.  At this point SCons will use the defined
 673 # build environments to build the requested targets.
 674 #
 675 ###################################################
 676