3 # Copyright (c) 2013, 2015-2020 ARM Limited
6 # The license below extends only to copyright in the software and shall
7 # not be construed as granting a license to any other intellectual
8 # property including but not limited to intellectual property relating
9 # to a hardware implementation of the functionality of the software
10 # licensed hereunder. You may use the software subject to the license
11 # terms below provided that you ensure that this notice is replicated
12 # unmodified and in its entirety in all distributions of the software,
13 # modified or unmodified, in source code or in binary form.
15 # Copyright (c) 2011 Advanced Micro Devices, Inc.
16 # Copyright (c) 2009 The Hewlett-Packard Development Company
17 # Copyright (c) 2004-2005 The Regents of The University of Michigan
18 # All rights reserved.
20 # Redistribution and use in source and binary forms, with or without
21 # modification, are permitted provided that the following conditions are
22 # met: redistributions of source code must retain the above copyright
23 # notice, this list of conditions and the following disclaimer;
24 # redistributions in binary form must reproduce the above copyright
25 # notice, this list of conditions and the following disclaimer in the
26 # documentation and/or other materials provided with the distribution;
27 # neither the name of the copyright holders nor the names of its
28 # contributors may be used to endorse or promote products derived from
29 # this software without specific prior written permission.
31 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
37 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
38 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
39 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
40 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
41 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 ###################################################
45 # SCons top-level build description (SConstruct) file.
47 # While in this directory ('gem5'), just type 'scons' to build the default
48 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
49 # to build some other configuration (e.g., 'build/X86/gem5.opt' for
50 # the optimized full-system version).
52 # You can build gem5 in a different directory as long as there is a
53 # 'build/<CONFIG>' somewhere along the target path. The build system
54 # expects that all configs under the same build directory are being
55 # built for the same host system.
59 # The following two commands are equivalent. The '-u' option tells
60 # scons to search up the directory tree for this SConstruct file.
61 # % cd <path-to-src>/gem5 ; scons build/X86/gem5.debug
62 # % cd <path-to-src>/gem5/build/X86; scons -u gem5.debug
64 # The following two commands are equivalent and demonstrate building
65 # in a directory outside of the source tree. The '-C' option tells
66 # scons to chdir to the specified directory to find this SConstruct
68 # % cd <path-to-src>/gem5 ; scons /local/foo/build/X86/gem5.debug
69 # % cd /local/foo/build/X86; scons -C <path-to-src>/gem5 gem5.debug
71 # You can use 'scons -H' to print scons options. If you're in this
72 # 'gem5' directory (or use -u or -C to tell scons where to find this
73 # file), you can use 'scons -h' to print all the gem5-specific build
76 ###################################################
78 # Global Python includes
87 from os
import mkdir
, environ
88 from os
.path
import abspath
, basename
, dirname
, expanduser
, normpath
89 from os
.path
import exists
, isdir
, isfile
90 from os
.path
import join
as joinpath
, split
as splitpath
98 from m5
.util
import compareVersions
, readCommand
, readCommandWithReturn
100 AddOption('--colors', dest
='use_colors', action
='store_true',
101 help="Add color to abbreviated scons output")
102 AddOption('--no-colors', dest
='use_colors', action
='store_false',
103 help="Don't add color to abbreviated scons output")
104 AddOption('--with-cxx-config', action
='store_true',
105 help="Build with support for C++-based configuration")
106 AddOption('--default',
107 help='Override which build_opts file to use for defaults')
108 AddOption('--ignore-style', action
='store_true',
109 help='Disable style checking hooks')
110 AddOption('--gold-linker', action
='store_true', help='Use the gold linker')
111 AddOption('--no-lto', action
='store_true',
112 help='Disable Link-Time Optimization for fast')
113 AddOption('--force-lto', action
='store_true',
114 help='Use Link-Time Optimization instead of partial linking' +
115 ' when the compiler doesn\'t support using them together.')
116 AddOption('--verbose', action
='store_true',
117 help='Print full tool command lines')
118 AddOption('--without-python', action
='store_true',
119 help='Build without Python configuration support')
120 AddOption('--without-tcmalloc', action
='store_true',
121 help='Disable linking against tcmalloc')
122 AddOption('--with-ubsan', action
='store_true',
123 help='Build with Undefined Behavior Sanitizer if available')
124 AddOption('--with-asan', action
='store_true',
125 help='Build with Address Sanitizer if available')
126 AddOption('--with-systemc-tests', action
='store_true',
127 help='Build systemc tests')
129 from gem5_scons
import Transform
, error
, warning
, summarize_warnings
131 if GetOption('no_lto') and GetOption('force_lto'):
132 error('--no-lto and --force-lto are mutually exclusive')
134 ########################################################################
136 # Set up the main build environment.
138 ########################################################################
140 main
= Environment(tools
=['default', 'git'])
142 from gem5_scons
.util
import get_termcap
143 termcap
= get_termcap()
145 main_dict_keys
= main
.Dictionary().keys()
147 # Check that we have a C/C++ compiler
148 if not ('CC' in main_dict_keys
and 'CXX' in main_dict_keys
):
149 error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
151 ###################################################
153 # Figure out which configurations to set up based on the path(s) of
156 ###################################################
158 # Find default configuration & binary.
159 Default(environ
.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
161 # helper function: find last occurrence of element in list
162 def rfind(l
, elt
, offs
= -1):
163 for i
in range(len(l
)+offs
, 0, -1):
166 raise ValueError("element not found")
168 # Take a list of paths (or SCons Nodes) and return a list with all
169 # paths made absolute and ~-expanded. Paths will be interpreted
170 # relative to the launch directory unless a different root is provided
171 def makePathListAbsolute(path_list
, root
=GetLaunchDir()):
172 return [abspath(joinpath(root
, expanduser(str(p
))))
175 # Each target must have 'build' in the interior of the path; the
176 # directory below this will determine the build parameters. For
177 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
178 # recognize that X86 specifies the configuration because it
179 # follow 'build' in the build path.
181 # The funky assignment to "[:]" is needed to replace the list contents
182 # in place rather than reassign the symbol to a new list, which
183 # doesn't work (obviously!).
184 BUILD_TARGETS
[:] = makePathListAbsolute(BUILD_TARGETS
)
186 # Generate a list of the unique build roots and configs that the
187 # collected targets reference.
190 for t
in BUILD_TARGETS
:
191 path_dirs
= t
.split('/')
193 build_top
= rfind(path_dirs
, 'build', -2)
195 error("No non-leaf 'build' dir found on target path.", t
)
196 this_build_root
= joinpath('/',*path_dirs
[:build_top
+1])
198 build_root
= this_build_root
200 if this_build_root
!= build_root
:
201 error("build targets not under same build root\n"
202 " %s\n %s" % (build_root
, this_build_root
))
203 variant_path
= joinpath('/',*path_dirs
[:build_top
+2])
204 if variant_path
not in variant_paths
:
205 variant_paths
.append(variant_path
)
207 # Make sure build_root exists (might not if this is the first build there)
208 if not isdir(build_root
):
210 main
['BUILDROOT'] = build_root
214 main
.SConsignFile(joinpath(build_root
, "sconsign"))
216 # Default duplicate option is to use hard links, but this messes up
217 # when you use emacs to edit a file in the target dir, as emacs moves
218 # file to file~ then copies to file, breaking the link. Symbolic
219 # (soft) links work better.
220 main
.SetOption('duplicate', 'soft-copy')
223 # Set up global sticky variables... these are common to an entire build
224 # tree (not specific to a particular build like X86)
227 global_vars_file
= joinpath(build_root
, 'variables.global')
229 global_vars
= Variables(global_vars_file
, args
=ARGUMENTS
)
231 global_vars
.AddVariables(
232 ('CC', 'C compiler', environ
.get('CC', main
['CC'])),
233 ('CXX', 'C++ compiler', environ
.get('CXX', main
['CXX'])),
234 ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
235 ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
236 ('MARSHAL_CCFLAGS_EXTRA', 'Extra C and C++ marshal compiler flags', ''),
237 ('MARSHAL_LDFLAGS_EXTRA', 'Extra marshal linker flags', ''),
238 ('PYTHON_CONFIG', 'Python config binary to use',
239 [ 'python3-config', 'python-config']
241 ('PROTOC', 'protoc tool', environ
.get('PROTOC', 'protoc')),
242 ('BATCH', 'Use batch pool for build and tests', False),
243 ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
244 ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
245 ('EXTRAS', 'Add extra directories to the compilation', '')
248 # Update main environment with values from ARGUMENTS & global_vars_file
249 global_vars
.Update(main
)
251 Global build variables:
253 '''.format(help=global_vars
.GenerateHelpText(main
)), append
=True)
255 # Save sticky variable settings back to current variables file
256 global_vars
.Save(global_vars_file
, main
)
258 # Parse EXTRAS variable to build list of all directories where we're
259 # look for sources etc. This list is exported as extras_dir_list.
260 base_dir
= Dir('#src').abspath
262 extras_dir_list
= makePathListAbsolute(main
['EXTRAS'].split(':'))
267 Export('extras_dir_list')
269 # the ext directory should be on the #includes path
270 main
.Append(CPPPATH
=[Dir('ext')])
272 # Add shared top-level headers
273 main
.Prepend(CPPPATH
=Dir('include'))
275 if GetOption('verbose'):
276 def MakeAction(action
, string
, *args
, **kwargs
):
277 return Action(action
, *args
, **kwargs
)
280 main
['CCCOMSTR'] = Transform("CC")
281 main
['CXXCOMSTR'] = Transform("CXX")
282 main
['ASCOMSTR'] = Transform("AS")
283 main
['ARCOMSTR'] = Transform("AR", 0)
284 main
['LINKCOMSTR'] = Transform("LINK", 0)
285 main
['SHLINKCOMSTR'] = Transform("SHLINK", 0)
286 main
['RANLIBCOMSTR'] = Transform("RANLIB", 0)
287 main
['M4COMSTR'] = Transform("M4")
288 main
['SHCCCOMSTR'] = Transform("SHCC")
289 main
['SHCXXCOMSTR'] = Transform("SHCXX")
292 # Initialize the Link-Time Optimization (LTO) flags
293 main
['LTO_CCFLAGS'] = []
294 main
['LTO_LDFLAGS'] = []
296 # According to the readme, tcmalloc works best if the compiler doesn't
297 # assume that we're using the builtin malloc and friends. These flags
298 # are compiler-specific, so we need to set them after we detect which
299 # compiler we're using.
300 main
['TCMALLOC_CCFLAGS'] = []
302 CXX_version
= readCommand([main
['CXX'],'--version'], exception
=False)
303 CXX_V
= readCommand([main
['CXX'],'-V'], exception
=False)
305 main
['GCC'] = CXX_version
and CXX_version
.find('g++') >= 0
306 main
['CLANG'] = CXX_version
and CXX_version
.find('clang') >= 0
307 if main
['GCC'] + main
['CLANG'] > 1:
308 error('Two compilers enabled at once?')
310 # Set up default C++ compiler flags
311 if main
['GCC'] or main
['CLANG']:
312 # As gcc and clang share many flags, do the common parts here
313 main
.Append(CCFLAGS
=['-pipe'])
314 main
.Append(CCFLAGS
=['-fno-strict-aliasing'])
315 # Enable -Wall and -Wextra and then disable the few warnings that
316 # we consistently violate
317 main
.Append(CCFLAGS
=['-Wall', '-Wundef', '-Wextra',
318 '-Wno-sign-compare', '-Wno-unused-parameter'])
319 # We always compile using C++14
320 main
.Append(CXXFLAGS
=['-std=c++14'])
321 if sys
.platform
.startswith('freebsd'):
322 main
.Append(CCFLAGS
=['-I/usr/local/include'])
323 main
.Append(CXXFLAGS
=['-I/usr/local/include'])
325 # On Mac OS X/Darwin the default linker doesn't support the
327 if sys
.platform
!= "darwin":
328 main
.Append(LINKFLAGS
='-Wl,--as-needed')
329 main
['FILTER_PSHLINKFLAGS'] = lambda x
: str(x
).replace(' -shared', '')
330 main
['PSHLINKFLAGS'] = main
.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
331 if GetOption('gold_linker'):
332 main
.Append(LINKFLAGS
='-fuse-ld=gold')
333 main
['PLINKFLAGS'] = main
.get('LINKFLAGS')
334 shared_partial_flags
= ['-r', '-nostdlib']
335 main
.Append(PSHLINKFLAGS
=shared_partial_flags
)
336 main
.Append(PLINKFLAGS
=shared_partial_flags
)
338 # Treat warnings as errors but white list some warnings that we
339 # want to allow (e.g., deprecation warnings).
340 main
.Append(CCFLAGS
=['-Werror',
341 '-Wno-error=deprecated-declarations',
342 '-Wno-error=deprecated',
346 "Don't know what compiler options to use for your compiler.",
347 "compiler: " + main
['CXX'],
348 "version: " + CXX_version
.replace('\n', '<nl>') if
349 CXX_version
else 'COMMAND NOT FOUND!',
350 "If you're trying to use a compiler other than GCC",
351 "or clang, there appears to be something wrong with your",
354 "If you are trying to use a compiler other than those listed",
355 "above you will need to ease fix SConstruct and ",
356 "src/SConscript to support that compiler.")))
359 gcc_version
= readCommand([main
['CXX'], '-dumpversion'], exception
=False)
360 if compareVersions(gcc_version
, "5") < 0:
361 error('gcc version 5 or newer required.\n'
362 'Installed version:', gcc_version
)
365 main
['GCC_VERSION'] = gcc_version
367 # Incremental linking with LTO is currently broken in gcc versions
368 # 4.9 and above. A version where everything works completely hasn't
369 # yet been identified.
371 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
372 main
['BROKEN_INCREMENTAL_LTO'] = True
374 if compareVersions(gcc_version
, '6.0') >= 0:
375 # gcc versions 6.0 and greater accept an -flinker-output flag which
376 # selects what type of output the linker should generate. This is
377 # necessary for incremental lto to work, but is also broken in
378 # current versions of gcc. It may not be necessary in future
379 # versions. We add it here since it might be, and as a reminder that
380 # it exists. It's excluded if lto is being forced.
382 # https://gcc.gnu.org/gcc-6/changes.html
383 # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
384 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
385 if not GetOption('force_lto'):
386 main
.Append(PSHLINKFLAGS
='-flinker-output=rel')
387 main
.Append(PLINKFLAGS
='-flinker-output=rel')
389 disable_lto
= GetOption('no_lto')
390 if not disable_lto
and main
.get('BROKEN_INCREMENTAL_LTO', False) and \
391 not GetOption('force_lto'):
392 warning('Your compiler doesn\'t support incremental linking and lto '
393 'at the same time, so lto is being disabled. To force lto on '
394 'anyway, use the --force-lto option. That will disable '
398 # Add the appropriate Link-Time Optimization (LTO) flags
399 # unless LTO is explicitly turned off. Note that these flags
400 # are only used by the fast target.
402 # Pass the LTO flag when compiling to produce GIMPLE
403 # output, we merely create the flags here and only append
405 main
['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
407 # Use the same amount of jobs for LTO as we are running
409 main
['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
411 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin-malloc', '-fno-builtin-calloc',
412 '-fno-builtin-realloc', '-fno-builtin-free'])
415 clang_version_re
= re
.compile(".* version (\d+\.\d+)")
416 clang_version_match
= clang_version_re
.search(CXX_version
)
417 if (clang_version_match
):
418 clang_version
= clang_version_match
.groups()[0]
419 if compareVersions(clang_version
, "3.9") < 0:
420 error('clang version 3.9 or newer required.\n'
421 'Installed version:', clang_version
)
423 error('Unable to determine clang version.')
425 # clang has a few additional warnings that we disable, extraneous
426 # parantheses are allowed due to Ruby's printing of the AST,
427 # finally self assignments are allowed as the generated CPU code
429 main
.Append(CCFLAGS
=['-Wno-parentheses',
431 # Some versions of libstdc++ (4.8?) seem to
432 # use struct hash and class hash
434 '-Wno-mismatched-tags',
436 if sys
.platform
!= "darwin" and \
437 compareVersions(clang_version
, "10.0") >= 0:
438 main
.Append(CCFLAGS
=['-Wno-c99-designator'])
440 if compareVersions(clang_version
, "8.0") >= 0:
441 main
.Append(CCFLAGS
=['-Wno-defaulted-function-deleted'])
443 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin'])
445 # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
446 # opposed to libstdc++, as the later is dated.
447 if sys
.platform
== "darwin":
448 main
.Append(CXXFLAGS
=['-stdlib=libc++'])
449 main
.Append(LIBS
=['c++'])
451 # On FreeBSD we need libthr.
452 if sys
.platform
.startswith('freebsd'):
453 main
.Append(LIBS
=['thr'])
455 # Add sanitizers flags
457 if GetOption('with_ubsan'):
458 sanitizers
.append('undefined')
459 if GetOption('with_asan'):
460 # Available for gcc >= 5 or llvm >= 3.1 both a requirement
461 # by the build system
462 sanitizers
.append('address')
463 suppressions_file
= Dir('util').File('lsan-suppressions').get_abspath()
464 suppressions_opt
= 'suppressions=%s' % suppressions_file
465 main
['ENV']['LSAN_OPTIONS'] = ':'.join([suppressions_opt
,
466 'print_suppressions=0'])
468 warning('To suppress false positive leaks, set the LSAN_OPTIONS '
469 'environment variable to "%s" when running gem5' %
471 warning('LSAN_OPTIONS=suppressions=%s' % suppressions_opt
)
474 sanitizers
= ','.join(sanitizers
)
475 if main
['GCC'] or main
['CLANG']:
476 main
.Append(CCFLAGS
=['-fsanitize=%s' % sanitizers
,
477 '-fno-omit-frame-pointer'],
478 LINKFLAGS
='-fsanitize=%s' % sanitizers
)
480 warning("Don't know how to enable %s sanitizer(s) for your "
481 "compiler." % sanitizers
)
483 # Set up common yacc/bison flags (needed for Ruby)
484 main
['YACCFLAGS'] = '-d'
485 main
['YACCHXXFILESUFFIX'] = '.hh'
487 # Do this after we save setting back, or else we'll tack on an
488 # extra 'qdo' every time we run scons.
490 main
['CC'] = main
['BATCH_CMD'] + ' ' + main
['CC']
491 main
['CXX'] = main
['BATCH_CMD'] + ' ' + main
['CXX']
492 main
['AS'] = main
['BATCH_CMD'] + ' ' + main
['AS']
493 main
['AR'] = main
['BATCH_CMD'] + ' ' + main
['AR']
494 main
['RANLIB'] = main
['BATCH_CMD'] + ' ' + main
['RANLIB']
496 if sys
.platform
== 'cygwin':
497 # cygwin has some header file issues...
498 main
.Append(CCFLAGS
=["-Wno-uninitialized"])
501 have_pkg_config
= readCommand(['pkg-config', '--version'], exception
='')
503 # Check for the protobuf compiler
505 main
['HAVE_PROTOC'] = True
506 protoc_version
= readCommand([main
['PROTOC'], '--version']).split()
508 # First two words should be "libprotoc x.y.z"
509 if len(protoc_version
) < 2 or protoc_version
[0] != 'libprotoc':
510 warning('Protocol buffer compiler (protoc) not found.\n'
511 'Please install protobuf-compiler for tracing support.')
512 main
['HAVE_PROTOC'] = False
514 # Based on the availability of the compress stream wrappers,
516 min_protoc_version
= '2.1.0'
517 if compareVersions(protoc_version
[1], min_protoc_version
) < 0:
518 warning('protoc version', min_protoc_version
,
519 'or newer required.\n'
520 'Installed version:', protoc_version
[1])
521 main
['HAVE_PROTOC'] = False
523 # Attempt to determine the appropriate include path and
524 # library path using pkg-config, that means we also need to
525 # check for pkg-config. Note that it is possible to use
526 # protobuf without the involvement of pkg-config. Later on we
527 # check go a library config check and at that point the test
528 # will fail if libprotobuf cannot be found.
531 # Attempt to establish what linking flags to add for
535 'pkg-config --cflags --libs-only-L protobuf')
537 warning('pkg-config could not get protobuf flags.')
538 except Exception as e
:
539 warning('While checking protoc version:', str(e
))
540 main
['HAVE_PROTOC'] = False
542 # Check for 'timeout' from GNU coreutils. If present, regressions will
543 # be run with a time limit. We require version 8.13 since we rely on
544 # support for the '--foreground' option.
545 if sys
.platform
.startswith('freebsd'):
546 timeout_lines
= readCommand(['gtimeout', '--version'],
547 exception
='').splitlines()
549 timeout_lines
= readCommand(['timeout', '--version'],
550 exception
='').splitlines()
551 # Get the first line and tokenize it
552 timeout_version
= timeout_lines
[0].split() if timeout_lines
else []
553 main
['TIMEOUT'] = timeout_version
and \
554 compareVersions(timeout_version
[-1], '8.13') >= 0
556 # Add a custom Check function to test for structure members.
557 def CheckMember(context
, include
, decl
, member
, include_quotes
="<>"):
558 context
.Message("Checking for member %s in %s..." %
564 (void)test.%(member)s;
567 """ % { "header" : include_quotes
[0] + include
+ include_quotes
[1],
572 ret
= context
.TryCompile(text
, extension
=".cc")
576 def CheckPythonLib(context
):
577 context
.Message('Checking Python version... ')
578 ret
= context
.TryRun(r
"""
579 #include <pybind11/embed.h>
582 main(int argc, char **argv) {
583 pybind11::scoped_interpreter guard{};
586 "vi = sys.version_info\n"
587 "sys.stdout.write('%i.%i.%i' % (vi.major, vi.minor, vi.micro));\n");
590 """, extension
=".cc")
591 context
.Result(ret
[1] if ret
[0] == 1 else 0)
595 return tuple(map(int, ret
[1].split(".")))
597 # Platform-specific configuration. Note again that we assume that all
598 # builds under a given build root run on the same host platform.
599 conf
= Configure(main
,
600 conf_dir
= joinpath(build_root
, '.scons_config'),
601 log_file
= joinpath(build_root
, 'scons_config.log'),
603 'CheckMember' : CheckMember
,
604 'CheckPythonLib' : CheckPythonLib
,
607 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
610 uname
= platform
.uname()
611 if uname
[0] == 'Darwin' and compareVersions(uname
[2], '9.0.0') >= 0:
612 if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
613 main
.Append(CCFLAGS
=['-arch', 'x86_64'])
614 main
.Append(CFLAGS
=['-arch', 'x86_64'])
615 main
.Append(LINKFLAGS
=['-arch', 'x86_64'])
616 main
.Append(ASFLAGS
=['-arch', 'x86_64'])
620 # Recent versions of scons substitute a "Null" object for Configure()
621 # when configuration isn't necessary, e.g., if the "--help" option is
622 # present. Unfortuantely this Null object always returns false,
623 # breaking all our configuration checks. We replace it with our own
624 # more optimistic null object that returns True instead.
626 def NullCheck(*args
, **kwargs
):
630 def __init__(self
, env
):
634 def __getattr__(self
, mname
):
637 conf
= NullConf(main
)
639 # Cache build files in the supplied directory.
640 if main
['M5_BUILD_CACHE']:
641 print('Using build cache located at', main
['M5_BUILD_CACHE'])
642 CacheDir(main
['M5_BUILD_CACHE'])
644 main
['USE_PYTHON'] = not GetOption('without_python')
645 if main
['USE_PYTHON']:
646 # Find Python include and library directories for embedding the
647 # interpreter. We rely on python-config to resolve the appropriate
648 # includes and linker flags. ParseConfig does not seem to understand
649 # the more exotic linker flags such as -Xlinker and -export-dynamic so
650 # we add them explicitly below. If you want to link in an alternate
651 # version of python, see above for instructions on how to invoke
652 # scons with the appropriate PATH set.
654 python_config
= main
.Detect(main
['PYTHON_CONFIG'])
655 if python_config
is None:
656 error("Can't find a suitable python-config, tried %s" % \
657 main
['PYTHON_CONFIG'])
659 print("Info: Using Python config: %s" % (python_config
, ))
661 py_includes
= readCommand([python_config
, '--includes'],
662 exception
='').split()
663 py_includes
= list(filter(
664 lambda s
: match(r
'.*\/include\/.*',s
), py_includes
))
665 # Strip the -I from the include folders before adding them to the
667 py_includes
= list(map(
668 lambda s
: s
[2:] if s
.startswith('-I') else s
, py_includes
))
669 main
.Append(CPPPATH
=py_includes
)
671 # Read the linker flags and split them into libraries and other link
672 # flags. The libraries are added later through the call the CheckLib.
673 # Note: starting in Python 3.8 the --embed flag is required to get the
674 # -lpython3.8 linker flag
675 retcode
, cmd_stdout
= readCommandWithReturn(
676 [python_config
, '--ldflags', '--embed'], exception
='')
678 # If --embed isn't detected then we're running python <3.8
679 retcode
, cmd_stdout
= readCommandWithReturn(
680 [python_config
, '--ldflags'], exception
='')
682 # Checking retcode again
684 error("Failing on python-config --ldflags command")
686 py_ld_flags
= cmd_stdout
.split()
689 for lib
in py_ld_flags
:
690 if not lib
.startswith('-l'):
691 main
.Append(LINKFLAGS
=[lib
])
694 if lib
not in py_libs
:
697 # verify that this stuff works
698 if not conf
.CheckHeader('Python.h', '<>'):
699 error("Check failed for Python.h header in",
700 ' '.join(py_includes
), "\n"
701 "Two possible reasons:\n"
702 "1. Python headers are not installed (You can install the "
703 "package python-dev on Ubuntu and RedHat)\n"
704 "2. SCons is using a wrong C compiler. This can happen if "
705 "CC has the wrong value.\n"
706 "CC = %s" % main
['CC'])
709 if not conf
.CheckLib(lib
):
710 error("Can't find library %s required by python." % lib
)
712 main
.Prepend(CPPPATH
=Dir('ext/pybind11/include/'))
714 marshal_env
= main
.Clone()
716 # Bare minimum environment that only includes python
717 marshal_env
.Append(CCFLAGS
='$MARSHAL_CCFLAGS_EXTRA')
718 marshal_env
.Append(LINKFLAGS
='$MARSHAL_LDFLAGS_EXTRA')
720 py_version
= conf
.CheckPythonLib()
722 error("Can't find a working Python installation")
724 # Found a working Python installation. Check if it meets minimum
726 if py_version
[0] < 3 or \
727 (py_version
[0] == 3 and py_version
[1] < 6):
728 error('Python version too old. Version 3.6 or newer is required.')
729 elif py_version
[0] > 3:
730 warning('Python version too new. Python 3 expected.')
732 # On Solaris you need to use libsocket for socket ops
733 if not conf
.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
734 if not conf
.CheckLibWithHeader('socket', 'sys/socket.h',
735 'C++', 'accept(0,0,0);'):
736 error("Can't find library with socket calls (e.g. accept()).")
738 # Check for zlib. If the check passes, libz will be automatically
739 # added to the LIBS environment variable.
740 if not conf
.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
741 error('Did not find needed zlib compression library '
742 'and/or zlib.h header file.\n'
743 'Please install zlib and try again.')
745 # If we have the protobuf compiler, also make sure we have the
746 # development libraries. If the check passes, libprotobuf will be
747 # automatically added to the LIBS environment variable. After
748 # this, we can use the HAVE_PROTOBUF flag to determine if we have
749 # got both protoc and libprotobuf available.
750 main
['HAVE_PROTOBUF'] = main
['HAVE_PROTOC'] and \
751 conf
.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
752 'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
754 # Valgrind gets much less confused if you tell it when you're using
755 # alternative stacks.
756 main
['HAVE_VALGRIND'] = conf
.CheckCHeader('valgrind/valgrind.h')
758 # If we have the compiler but not the library, print another warning.
759 if main
['HAVE_PROTOC'] and not main
['HAVE_PROTOBUF']:
760 warning('Did not find protocol buffer library and/or headers.\n'
761 'Please install libprotobuf-dev for tracing support.')
765 conf
.CheckLibWithHeader(None, 'time.h', 'C',
766 'clock_nanosleep(0,0,NULL,NULL);') or \
767 conf
.CheckLibWithHeader('rt', 'time.h', 'C',
768 'clock_nanosleep(0,0,NULL,NULL);')
770 have_posix_timers
= \
771 conf
.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
772 'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
774 if not GetOption('without_tcmalloc'):
775 if conf
.CheckLib('tcmalloc'):
776 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
777 elif conf
.CheckLib('tcmalloc_minimal'):
778 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
780 warning("You can get a 12% performance improvement by "
781 "installing tcmalloc (libgoogle-perftools-dev package "
782 "on Ubuntu or RedHat).")
785 # Detect back trace implementations. The last implementation in the
786 # list will be used by default.
787 backtrace_impls
= [ "none" ]
789 backtrace_checker
= 'char temp;' + \
790 ' backtrace_symbols_fd((void*)&temp, 0, 0);'
791 if conf
.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker
):
792 backtrace_impls
.append("glibc")
793 elif conf
.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
795 # NetBSD and FreeBSD need libexecinfo.
796 backtrace_impls
.append("glibc")
797 main
.Append(LIBS
=['execinfo'])
799 if backtrace_impls
[-1] == "none":
800 default_backtrace_impl
= "none"
801 warning("No suitable back trace implementation found.")
803 if not have_posix_clock
:
804 warning("Can't find library for POSIX clocks.")
806 # Check for <fenv.h> (C99 FP environment control)
807 have_fenv
= conf
.CheckHeader('fenv.h', '<>')
809 warning("Header file <fenv.h> not found.\n"
810 "This host has no IEEE FP rounding mode control.")
812 # Check for <png.h> (libpng library needed if wanting to dump
813 # frame buffer image in png format)
814 have_png
= conf
.CheckHeader('png.h', '<>')
816 warning("Header file <png.h> not found.\n"
817 "This host has no libpng library.\n"
818 "Disabling support for PNG framebuffers.")
820 # Check if we should enable KVM-based hardware virtualization. The API
821 # we rely on exists since version 2.6.36 of the kernel, but somehow
822 # the KVM_API_VERSION does not reflect the change. We test for one of
823 # the types as a fall back.
824 have_kvm
= conf
.CheckHeader('linux/kvm.h', '<>')
826 print("Info: Compatible header file <linux/kvm.h> not found, "
827 "disabling KVM support.")
829 # Check if the TUN/TAP driver is available.
830 have_tuntap
= conf
.CheckHeader('linux/if_tun.h', '<>')
832 print("Info: Compatible header file <linux/if_tun.h> not found.")
834 # x86 needs support for xsave. We test for the structure here since we
835 # won't be able to run new tests by the time we know which ISA we're
837 have_kvm_xsave
= conf
.CheckTypeSize('struct kvm_xsave',
838 '#include <linux/kvm.h>') != 0
840 # Check if the requested target ISA is compatible with the host
841 def is_isa_kvm_compatible(isa
):
844 host_isa
= platform
.machine()
846 warning("Failed to determine host ISA.")
849 if not have_posix_timers
:
850 warning("Can not enable KVM, host seems to lack support "
855 return host_isa
in ( "armv7l", "aarch64" )
857 if host_isa
!= "x86_64":
860 if not have_kvm_xsave
:
861 warning("KVM on x86 requires xsave support in kernel headers.")
869 # Check if the exclude_host attribute is available. We want this to
870 # get accurate instruction counts in KVM.
871 main
['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf
.CheckMember(
872 'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
876 conf
.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
877 'H5Fcreate("", 0, 0, 0);') and \
878 conf
.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
879 'H5::H5File("", 0);')
881 def check_hdf5_pkg(name
):
882 print("Checking for %s using pkg-config..." % name
, end
="")
883 if not have_pkg_config
:
884 print(" pkg-config not found")
888 main
.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name
)
895 # Check if there is a pkg-config configuration for hdf5. If we find
896 # it, setup the environment to enable linking and header inclusion. We
897 # don't actually try to include any headers or link with hdf5 at this
899 if not check_hdf5_pkg('hdf5-serial'):
900 check_hdf5_pkg('hdf5')
902 # Check if the HDF5 libraries can be found. This check respects the
903 # include path and library path provided by pkg-config. We perform
904 # this check even if there isn't a pkg-config configuration for hdf5
905 # since some installations don't use pkg-config.
906 have_hdf5
= check_hdf5()
908 print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
909 print(" HDF5 support.")
911 ######################################################################
913 # Finish the configuration
917 ######################################################################
919 # Collect all non-global variables
922 # Define the universe of supported ISAs
924 all_gpu_isa_list
= [ ]
925 Export('all_isa_list')
926 Export('all_gpu_isa_list')
928 class CpuModel(object):
929 '''The CpuModel class encapsulates everything the ISA parser needs to
930 know about a particular CPU model.'''
932 # Dict of available CPU model objects. Accessible as CpuModel.dict.
935 # Constructor. Automatically adds models to CpuModel.dict.
936 def __init__(self
, name
, default
=False):
937 self
.name
= name
# name of model
939 # This cpu is enabled by default
940 self
.default
= default
943 if name
in CpuModel
.dict:
944 raise AttributeError("CpuModel '%s' already registered" % name
)
945 CpuModel
.dict[name
] = self
949 # Sticky variables get saved in the variables file so they persist from
950 # one invocation to the next (unless overridden, in which case the new
951 # value becomes sticky).
952 sticky_vars
= Variables(args
=ARGUMENTS
)
953 Export('sticky_vars')
955 # Sticky variables that should be exported
957 Export('export_vars')
961 Export('all_protocols')
963 Export('protocol_dirs')
965 Export('slicc_includes')
967 # Walk the tree and execute all SConsopts scripts that wil add to the
969 if GetOption('verbose'):
970 print("Reading SConsopts")
971 for bdir
in [ base_dir
] + extras_dir_list
:
973 error("Directory '%s' does not exist." % bdir
)
974 for root
, dirs
, files
in os
.walk(bdir
):
975 if 'SConsopts' in files
:
976 if GetOption('verbose'):
977 print("Reading", joinpath(root
, 'SConsopts'))
978 SConscript(joinpath(root
, 'SConsopts'))
981 all_gpu_isa_list
.sort()
983 sticky_vars
.AddVariables(
984 EnumVariable('TARGET_ISA', 'Target ISA', 'null', all_isa_list
),
985 EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'gcn3', all_gpu_isa_list
),
986 ListVariable('CPU_MODELS', 'CPU models',
987 sorted(n
for n
,m
in CpuModel
.dict.items() if m
.default
),
988 sorted(CpuModel
.dict.keys())),
989 BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
991 BoolVariable('USE_SSE2',
992 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
994 BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock
),
995 BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv
),
996 BoolVariable('USE_PNG', 'Enable support for PNG images', have_png
),
997 BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
999 BoolVariable('USE_TUNTAP',
1000 'Enable using a tap device to bridge to the host network',
1002 BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1003 EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1005 EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1006 backtrace_impls
[-1], backtrace_impls
),
1007 ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
1009 BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5
),
1012 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1013 export_vars
+= ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA',
1014 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
1015 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1016 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1017 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1019 ###################################################
1021 # Define a SCons builder for configuration flag headers.
1023 ###################################################
1025 # This function generates a config header file that #defines the
1026 # variable symbol to the current variable setting (0 or 1). The source
1027 # operands are the name of the variable and a Value node containing the
1028 # value of the variable.
1029 def build_config_file(target
, source
, env
):
1030 (variable
, value
) = [s
.get_contents().decode('utf-8') for s
in source
]
1031 with
open(str(target
[0].abspath
), 'w') as f
:
1032 print('#define', variable
, value
, file=f
)
1035 # Combine the two functions into a scons Action object.
1036 config_action
= MakeAction(build_config_file
, Transform("CONFIG H", 2))
1038 # The emitter munges the source & target node lists to reflect what
1039 # we're really doing.
1040 def config_emitter(target
, source
, env
):
1041 # extract variable name from Builder arg
1042 variable
= str(target
[0])
1043 # True target is config header file
1044 target
= Dir('config').File(variable
.lower() + '.hh')
1046 if isinstance(val
, bool):
1047 # Force value to 0/1
1049 elif isinstance(val
, str):
1050 val
= '"' + val
+ '"'
1052 # Sources are variable name & value (packaged in SCons Value nodes)
1053 return [target
], [Value(variable
), Value(val
)]
1055 config_builder
= Builder(emitter
=config_emitter
, action
=config_action
)
1057 main
.Append(BUILDERS
= { 'ConfigFile' : config_builder
})
1059 ###################################################
1061 # Builders for static and shared partially linked object files.
1063 ###################################################
1065 partial_static_builder
= Builder(action
=SCons
.Defaults
.LinkAction
,
1066 src_suffix
='$OBJSUFFIX',
1067 src_builder
=['StaticObject', 'Object'],
1068 LINKFLAGS
='$PLINKFLAGS',
1071 def partial_shared_emitter(target
, source
, env
):
1073 tgt
.attributes
.shared
= 1
1074 return (target
, source
)
1075 partial_shared_builder
= Builder(action
=SCons
.Defaults
.ShLinkAction
,
1076 emitter
=partial_shared_emitter
,
1077 src_suffix
='$SHOBJSUFFIX',
1078 src_builder
='SharedObject',
1079 SHLINKFLAGS
='$PSHLINKFLAGS',
1082 main
.Append(BUILDERS
= { 'PartialShared' : partial_shared_builder
,
1083 'PartialStatic' : partial_static_builder
})
1085 def add_local_rpath(env
, *targets
):
1086 '''Set up an RPATH for a library which lives in the build directory.
1088 The construction environment variable BIN_RPATH_PREFIX should be set to
1089 the relative path of the build directory starting from the location of the
1091 for target
in targets
:
1092 target
= env
.Entry(target
)
1093 if not isinstance(target
, SCons
.Node
.FS
.Dir
):
1095 relpath
= os
.path
.relpath(target
.abspath
, env
['BUILDDIR'])
1098 '${BIN_RPATH_PREFIX}',
1101 env
.Append(RPATH
=[env
.Literal(os
.path
.join(*components
))])
1103 if sys
.platform
!= "darwin":
1104 main
.Append(LINKFLAGS
=Split('-z origin'))
1106 main
.AddMethod(add_local_rpath
, 'AddLocalRPATH')
1108 # builds in ext are shared across all configs in the build root.
1109 ext_dir
= Dir('#ext').abspath
1111 for root
, dirs
, files
in os
.walk(ext_dir
):
1112 if 'SConscript' in files
:
1113 build_dir
= os
.path
.relpath(root
, ext_dir
)
1114 ext_build_dirs
.append(build_dir
)
1115 main
.SConscript(joinpath(root
, 'SConscript'),
1116 variant_dir
=joinpath(build_root
, build_dir
))
1118 gdb_xml_dir
= joinpath(ext_dir
, 'gdb-xml')
1119 Export('gdb_xml_dir')
1121 ###################################################
1123 # This builder and wrapper method are used to set up a directory with
1124 # switching headers. Those are headers which are in a generic location and
1125 # that include more specific headers from a directory chosen at build time
1126 # based on the current build settings.
1128 ###################################################
1130 def build_switching_header(target
, source
, env
):
1131 path
= str(target
[0])
1132 subdir
= str(source
[0])
1133 dp
, fp
= os
.path
.split(path
)
1134 dp
= os
.path
.relpath(os
.path
.realpath(dp
),
1135 os
.path
.realpath(env
['BUILDDIR']))
1136 with
open(path
, 'w') as hdr
:
1137 print('#include "%s/%s/%s"' % (dp
, subdir
, fp
), file=hdr
)
1139 switching_header_action
= MakeAction(build_switching_header
,
1140 Transform('GENERATE'))
1142 switching_header_builder
= Builder(action
=switching_header_action
,
1143 source_factory
=Value
,
1146 main
.Append(BUILDERS
= { 'SwitchingHeader': switching_header_builder
})
1148 def switching_headers(self
, headers
, source
):
1149 for header
in headers
:
1150 self
.SwitchingHeader(header
, source
)
1152 main
.AddMethod(switching_headers
, 'SwitchingHeaders')
1154 ###################################################
1156 # Define build environments for selected configurations.
1158 ###################################################
1160 for variant_path
in variant_paths
:
1161 if not GetOption('silent'):
1162 print("Building in", variant_path
)
1164 # Make a copy of the build-root environment to use for this config.
1166 env
['BUILDDIR'] = variant_path
1168 # variant_dir is the tail component of build path, and is used to
1169 # determine the build parameters (e.g., 'X86')
1170 (build_root
, variant_dir
) = splitpath(variant_path
)
1172 # Set env variables according to the build directory config.
1173 sticky_vars
.files
= []
1174 # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1175 # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1176 # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1177 current_vars_file
= joinpath(build_root
, 'variables', variant_dir
)
1178 if isfile(current_vars_file
):
1179 sticky_vars
.files
.append(current_vars_file
)
1180 if not GetOption('silent'):
1181 print("Using saved variables file %s" % current_vars_file
)
1182 elif variant_dir
in ext_build_dirs
:
1183 # Things in ext are built without a variant directory.
1186 # Build dir-specific variables file doesn't exist.
1188 # Make sure the directory is there so we can create it later
1189 opt_dir
= dirname(current_vars_file
)
1190 if not isdir(opt_dir
):
1193 # Get default build variables from source tree. Variables are
1194 # normally determined by name of $VARIANT_DIR, but can be
1195 # overridden by '--default=' arg on command line.
1196 default
= GetOption('default')
1197 opts_dir
= Dir('#build_opts').abspath
1199 default_vars_files
= [joinpath(build_root
, 'variables', default
),
1200 joinpath(opts_dir
, default
)]
1202 default_vars_files
= [joinpath(opts_dir
, variant_dir
)]
1203 existing_files
= list(filter(isfile
, default_vars_files
))
1205 default_vars_file
= existing_files
[0]
1206 sticky_vars
.files
.append(default_vars_file
)
1207 print("Variables file %s not found,\n using defaults in %s"
1208 % (current_vars_file
, default_vars_file
))
1210 error("Cannot find variables file %s or default file(s) %s"
1211 % (current_vars_file
, ' or '.join(default_vars_files
)))
1214 # Apply current variable settings to env
1215 sticky_vars
.Update(env
)
1218 Build variables for {dir}:
1220 '''.format(dir=variant_dir
, help=sticky_vars
.GenerateHelpText(env
)),
1223 # Process variable settings.
1225 if not have_fenv
and env
['USE_FENV']:
1226 warning("<fenv.h> not available; forcing USE_FENV to False in",
1228 env
['USE_FENV'] = False
1230 if not env
['USE_FENV']:
1231 warning("No IEEE FP rounding mode control in", variant_dir
+ ".\n"
1232 "FP results may deviate slightly from other platforms.")
1234 if not have_png
and env
['USE_PNG']:
1235 warning("<png.h> not available; forcing USE_PNG to False in",
1237 env
['USE_PNG'] = False
1240 env
.Append(LIBS
=['png'])
1243 env
.Append(LIBS
=['efence'])
1247 warning("Can not enable KVM, host seems to lack KVM support")
1248 env
['USE_KVM'] = False
1249 elif not is_isa_kvm_compatible(env
['TARGET_ISA']):
1250 print("Info: KVM support disabled due to unsupported host and "
1251 "target ISA combination")
1252 env
['USE_KVM'] = False
1254 if env
['USE_TUNTAP']:
1256 warning("Can't connect EtherTap with a tap device.")
1257 env
['USE_TUNTAP'] = False
1259 if env
['BUILD_GPU']:
1260 env
.Append(CPPDEFINES
=['BUILD_GPU'])
1262 # Warn about missing optional functionality
1264 if not main
['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1265 warning("perf_event headers lack support for the exclude_host "
1266 "attribute. KVM instruction counts will be inaccurate.")
1268 # Save sticky variable settings back to current variables file
1269 sticky_vars
.Save(current_vars_file
, env
)
1272 env
.Append(CCFLAGS
=['-msse2'])
1274 env
.Append(CCFLAGS
='$CCFLAGS_EXTRA')
1275 env
.Append(LINKFLAGS
='$LDFLAGS_EXTRA')
1278 if main
['USE_PYTHON']:
1279 exports
.append('marshal_env')
1281 # The src/SConscript file sets up the build rules in 'env' according
1282 # to the configured variables. It returns a list of environments,
1283 # one for each variant build (debug, opt, etc.)
1284 SConscript('src/SConscript', variant_dir
=variant_path
, exports
=exports
)
1286 atexit
.register(summarize_warnings
)