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 from __future__
import print_function
80 # Global Python includes
89 from os
import mkdir
, environ
90 from os
.path
import abspath
, basename
, dirname
, expanduser
, normpath
91 from os
.path
import exists
, isdir
, isfile
92 from os
.path
import join
as joinpath
, split
as splitpath
100 from m5
.util
import compareVersions
, readCommand
, readCommandWithReturn
102 AddOption('--colors', dest
='use_colors', action
='store_true',
103 help="Add color to abbreviated scons output")
104 AddOption('--no-colors', dest
='use_colors', action
='store_false',
105 help="Don't add color to abbreviated scons output")
106 AddOption('--with-cxx-config', action
='store_true',
107 help="Build with support for C++-based configuration")
108 AddOption('--default',
109 help='Override which build_opts file to use for defaults')
110 AddOption('--ignore-style', action
='store_true',
111 help='Disable style checking hooks')
112 AddOption('--gold-linker', action
='store_true', help='Use the gold linker')
113 AddOption('--no-lto', action
='store_true',
114 help='Disable Link-Time Optimization for fast')
115 AddOption('--force-lto', action
='store_true',
116 help='Use Link-Time Optimization instead of partial linking' +
117 ' when the compiler doesn\'t support using them together.')
118 AddOption('--verbose', action
='store_true',
119 help='Print full tool command lines')
120 AddOption('--without-python', action
='store_true',
121 help='Build without Python configuration support')
122 AddOption('--without-tcmalloc', action
='store_true',
123 help='Disable linking against tcmalloc')
124 AddOption('--with-ubsan', action
='store_true',
125 help='Build with Undefined Behavior Sanitizer if available')
126 AddOption('--with-asan', action
='store_true',
127 help='Build with Address Sanitizer if available')
128 AddOption('--with-systemc-tests', action
='store_true',
129 help='Build systemc tests')
131 from gem5_scons
import Transform
, error
, warning
, summarize_warnings
133 if GetOption('no_lto') and GetOption('force_lto'):
134 error('--no-lto and --force-lto are mutually exclusive')
136 ########################################################################
138 # Set up the main build environment.
140 ########################################################################
144 from gem5_scons
.util
import get_termcap
145 termcap
= get_termcap()
147 main_dict_keys
= main
.Dictionary().keys()
149 # Check that we have a C/C++ compiler
150 if not ('CC' in main_dict_keys
and 'CXX' in main_dict_keys
):
151 error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
153 ###################################################
155 # Figure out which configurations to set up based on the path(s) of
158 ###################################################
160 # Find default configuration & binary.
161 Default(environ
.get('M5_DEFAULT_BINARY', 'build/ARM/gem5.debug'))
163 # helper function: find last occurrence of element in list
164 def rfind(l
, elt
, offs
= -1):
165 for i
in range(len(l
)+offs
, 0, -1):
168 raise ValueError("element not found")
170 # Take a list of paths (or SCons Nodes) and return a list with all
171 # paths made absolute and ~-expanded. Paths will be interpreted
172 # relative to the launch directory unless a different root is provided
173 def makePathListAbsolute(path_list
, root
=GetLaunchDir()):
174 return [abspath(joinpath(root
, expanduser(str(p
))))
177 # Each target must have 'build' in the interior of the path; the
178 # directory below this will determine the build parameters. For
179 # example, for target 'foo/bar/build/X86/arch/x86/blah.do' we
180 # recognize that X86 specifies the configuration because it
181 # follow 'build' in the build path.
183 # The funky assignment to "[:]" is needed to replace the list contents
184 # in place rather than reassign the symbol to a new list, which
185 # doesn't work (obviously!).
186 BUILD_TARGETS
[:] = makePathListAbsolute(BUILD_TARGETS
)
188 # Generate a list of the unique build roots and configs that the
189 # collected targets reference.
192 for t
in BUILD_TARGETS
:
193 path_dirs
= t
.split('/')
195 build_top
= rfind(path_dirs
, 'build', -2)
197 error("No non-leaf 'build' dir found on target path.", t
)
198 this_build_root
= joinpath('/',*path_dirs
[:build_top
+1])
200 build_root
= this_build_root
202 if this_build_root
!= build_root
:
203 error("build targets not under same build root\n"
204 " %s\n %s" % (build_root
, this_build_root
))
205 variant_path
= joinpath('/',*path_dirs
[:build_top
+2])
206 if variant_path
not in variant_paths
:
207 variant_paths
.append(variant_path
)
209 # Make sure build_root exists (might not if this is the first build there)
210 if not isdir(build_root
):
212 main
['BUILDROOT'] = build_root
216 main
.SConsignFile(joinpath(build_root
, "sconsign"))
218 # Default duplicate option is to use hard links, but this messes up
219 # when you use emacs to edit a file in the target dir, as emacs moves
220 # file to file~ then copies to file, breaking the link. Symbolic
221 # (soft) links work better.
222 main
.SetOption('duplicate', 'soft-copy')
225 # Set up global sticky variables... these are common to an entire build
226 # tree (not specific to a particular build like X86)
229 global_vars_file
= joinpath(build_root
, 'variables.global')
231 global_vars
= Variables(global_vars_file
, args
=ARGUMENTS
)
233 global_vars
.AddVariables(
234 ('CC', 'C compiler', environ
.get('CC', main
['CC'])),
235 ('CXX', 'C++ compiler', environ
.get('CXX', main
['CXX'])),
236 ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
237 ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
238 ('MARSHAL_CCFLAGS_EXTRA', 'Extra C and C++ marshal compiler flags', ''),
239 ('MARSHAL_LDFLAGS_EXTRA', 'Extra marshal linker flags', ''),
240 ('PYTHON_CONFIG', 'Python config binary to use',
241 [ 'python2.7-config', 'python-config', 'python3-config' ]),
242 ('PROTOC', 'protoc tool', environ
.get('PROTOC', 'protoc')),
243 ('BATCH', 'Use batch pool for build and tests', False),
244 ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
245 ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
246 ('EXTRAS', 'Add extra directories to the compilation', '')
249 # Update main environment with values from ARGUMENTS & global_vars_file
250 global_vars
.Update(main
)
252 Global build variables:
254 '''.format(help=global_vars
.GenerateHelpText(main
)), append
=True)
256 # Save sticky variable settings back to current variables file
257 global_vars
.Save(global_vars_file
, main
)
259 # Parse EXTRAS variable to build list of all directories where we're
260 # look for sources etc. This list is exported as extras_dir_list.
261 base_dir
= main
.srcdir
.abspath
263 extras_dir_list
= makePathListAbsolute(main
['EXTRAS'].split(':'))
268 Export('extras_dir_list')
270 # the ext directory should be on the #includes path
271 main
.Append(CPPPATH
=[Dir('ext')])
273 # Add shared top-level headers
274 main
.Prepend(CPPPATH
=Dir('include'))
276 if GetOption('verbose'):
277 def MakeAction(action
, string
, *args
, **kwargs
):
278 return Action(action
, *args
, **kwargs
)
281 main
['CCCOMSTR'] = Transform("CC")
282 main
['CXXCOMSTR'] = Transform("CXX")
283 main
['ASCOMSTR'] = Transform("AS")
284 main
['ARCOMSTR'] = Transform("AR", 0)
285 main
['LINKCOMSTR'] = Transform("LINK", 0)
286 main
['SHLINKCOMSTR'] = Transform("SHLINK", 0)
287 main
['RANLIBCOMSTR'] = Transform("RANLIB", 0)
288 main
['M4COMSTR'] = Transform("M4")
289 main
['SHCCCOMSTR'] = Transform("SHCC")
290 main
['SHCXXCOMSTR'] = Transform("SHCXX")
293 # Initialize the Link-Time Optimization (LTO) flags
294 main
['LTO_CCFLAGS'] = []
295 main
['LTO_LDFLAGS'] = []
297 # According to the readme, tcmalloc works best if the compiler doesn't
298 # assume that we're using the builtin malloc and friends. These flags
299 # are compiler-specific, so we need to set them after we detect which
300 # compiler we're using.
301 main
['TCMALLOC_CCFLAGS'] = []
303 CXX_version
= readCommand([main
['CXX'],'--version'], exception
=False)
304 CXX_V
= readCommand([main
['CXX'],'-V'], exception
=False)
306 main
['GCC'] = CXX_version
and CXX_version
.find('g++') >= 0
307 main
['CLANG'] = CXX_version
and CXX_version
.find('clang') >= 0
308 if main
['GCC'] + main
['CLANG'] > 1:
309 error('Two compilers enabled at once?')
311 # Set up default C++ compiler flags
312 if main
['GCC'] or main
['CLANG']:
313 # As gcc and clang share many flags, do the common parts here
314 main
.Append(CCFLAGS
=['-pipe'])
315 main
.Append(CCFLAGS
=['-fno-strict-aliasing'])
316 # Enable -Wall and -Wextra and then disable the few warnings that
317 # we consistently violate
318 main
.Append(CCFLAGS
=['-Wall', '-Wundef', '-Wextra',
319 '-Wno-sign-compare', '-Wno-unused-parameter'])
320 # We always compile using C++11
321 main
.Append(CXXFLAGS
=['-std=c++11'])
322 if sys
.platform
.startswith('freebsd'):
323 main
.Append(CCFLAGS
=['-I/usr/local/include'])
324 main
.Append(CXXFLAGS
=['-I/usr/local/include'])
326 # On Mac OS X/Darwin the default linker doesn't support the
328 if sys
.platform
!= "darwin":
329 main
.Append(LINKFLAGS
='-Wl,--as-needed')
330 main
['FILTER_PSHLINKFLAGS'] = lambda x
: str(x
).replace(' -shared', '')
331 main
['PSHLINKFLAGS'] = main
.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
332 if GetOption('gold_linker'):
333 main
.Append(LINKFLAGS
='-fuse-ld=gold')
334 main
['PLINKFLAGS'] = main
.get('LINKFLAGS')
335 shared_partial_flags
= ['-r', '-nostdlib']
336 main
.Append(PSHLINKFLAGS
=shared_partial_flags
)
337 main
.Append(PLINKFLAGS
=shared_partial_flags
)
339 # Treat warnings as errors but white list some warnings that we
340 # want to allow (e.g., deprecation warnings).
341 main
.Append(CCFLAGS
=['-Werror',
342 '-Wno-error=deprecated-declarations',
343 '-Wno-error=deprecated',
347 "Don't know what compiler options to use for your compiler.",
348 "compiler: " + main
['CXX'],
349 "version: " + CXX_version
.replace('\n', '<nl>') if
350 CXX_version
else 'COMMAND NOT FOUND!',
351 "If you're trying to use a compiler other than GCC",
352 "or clang, there appears to be something wrong with your",
355 "If you are trying to use a compiler other than those listed",
356 "above you will need to ease fix SConstruct and ",
357 "src/SConscript to support that compiler.")))
360 # Check for a supported version of gcc. >= 4.8 is chosen for its
361 # level of c++11 support. See
362 # http://gcc.gnu.org/projects/cxx0x.html for details.
363 gcc_version
= readCommand([main
['CXX'], '-dumpversion'], exception
=False)
364 if compareVersions(gcc_version
, "4.8") < 0:
365 error('gcc version 4.8 or newer required.\n'
366 'Installed version:', gcc_version
)
369 main
['GCC_VERSION'] = gcc_version
371 if compareVersions(gcc_version
, '4.9') >= 0:
372 # Incremental linking with LTO is currently broken in gcc versions
373 # 4.9 and above. A version where everything works completely hasn't
374 # yet been identified.
376 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
377 main
['BROKEN_INCREMENTAL_LTO'] = True
378 if compareVersions(gcc_version
, '6.0') >= 0:
379 # gcc versions 6.0 and greater accept an -flinker-output flag which
380 # selects what type of output the linker should generate. This is
381 # necessary for incremental lto to work, but is also broken in
382 # current versions of gcc. It may not be necessary in future
383 # versions. We add it here since it might be, and as a reminder that
384 # it exists. It's excluded if lto is being forced.
386 # https://gcc.gnu.org/gcc-6/changes.html
387 # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
388 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
389 if not GetOption('force_lto'):
390 main
.Append(PSHLINKFLAGS
='-flinker-output=rel')
391 main
.Append(PLINKFLAGS
='-flinker-output=rel')
393 disable_lto
= GetOption('no_lto')
394 if not disable_lto
and main
.get('BROKEN_INCREMENTAL_LTO', False) and \
395 not GetOption('force_lto'):
396 warning('Your compiler doesn\'t support incremental linking and lto '
397 'at the same time, so lto is being disabled. To force lto on '
398 'anyway, use the --force-lto option. That will disable '
402 # Add the appropriate Link-Time Optimization (LTO) flags
403 # unless LTO is explicitly turned off. Note that these flags
404 # are only used by the fast target.
406 # Pass the LTO flag when compiling to produce GIMPLE
407 # output, we merely create the flags here and only append
409 main
['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
411 # Use the same amount of jobs for LTO as we are running
413 main
['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
415 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin-malloc', '-fno-builtin-calloc',
416 '-fno-builtin-realloc', '-fno-builtin-free'])
419 # Check for a supported version of clang, >= 3.1 is needed to
420 # support similar features as gcc 4.8. See
421 # http://clang.llvm.org/cxx_status.html for details
422 clang_version_re
= re
.compile(".* version (\d+\.\d+)")
423 clang_version_match
= clang_version_re
.search(CXX_version
)
424 if (clang_version_match
):
425 clang_version
= clang_version_match
.groups()[0]
426 if compareVersions(clang_version
, "3.1") < 0:
427 error('clang version 3.1 or newer required.\n'
428 'Installed version:', clang_version
)
430 error('Unable to determine clang version.')
432 # clang has a few additional warnings that we disable, extraneous
433 # parantheses are allowed due to Ruby's printing of the AST,
434 # finally self assignments are allowed as the generated CPU code
436 main
.Append(CCFLAGS
=['-Wno-parentheses',
438 # Some versions of libstdc++ (4.8?) seem to
439 # use struct hash and class hash
441 '-Wno-mismatched-tags',
443 if sys
.platform
!= "darwin" and \
444 compareVersions(clang_version
, "10.0") >= 0:
445 main
.Append(CCFLAGS
=['-Wno-c99-designator'])
447 if compareVersions(clang_version
, "8.0") >= 0:
448 main
.Append(CCFLAGS
=['-Wno-defaulted-function-deleted'])
450 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin'])
452 # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
453 # opposed to libstdc++, as the later is dated.
454 if sys
.platform
== "darwin":
455 main
.Append(CXXFLAGS
=['-stdlib=libc++'])
456 main
.Append(LIBS
=['c++'])
458 # On FreeBSD we need libthr.
459 if sys
.platform
.startswith('freebsd'):
460 main
.Append(LIBS
=['thr'])
462 # Add sanitizers flags
464 if GetOption('with_ubsan'):
465 # Only gcc >= 4.9 supports UBSan, so check both the version
466 # and the command-line option before adding the compiler and
468 if not main
['GCC'] or compareVersions(main
['GCC_VERSION'], '4.9') >= 0:
469 sanitizers
.append('undefined')
470 if GetOption('with_asan'):
471 # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
472 # by the build system
473 sanitizers
.append('address')
474 suppressions_file
= Dir('util').File('lsan-suppressions').get_abspath()
475 suppressions_opt
= 'suppressions=%s' % suppressions_file
476 main
['ENV']['LSAN_OPTIONS'] = ':'.join([suppressions_opt
,
477 'print_suppressions=0'])
479 warning('To suppress false positive leaks, set the LSAN_OPTIONS '
480 'environment variable to "%s" when running gem5' %
482 warning('LSAN_OPTIONS=suppressions=%s' % suppressions_opt
)
485 sanitizers
= ','.join(sanitizers
)
486 if main
['GCC'] or main
['CLANG']:
487 main
.Append(CCFLAGS
=['-fsanitize=%s' % sanitizers
,
488 '-fno-omit-frame-pointer'],
489 LINKFLAGS
='-fsanitize=%s' % sanitizers
)
491 warning("Don't know how to enable %s sanitizer(s) for your "
492 "compiler." % sanitizers
)
494 # Set up common yacc/bison flags (needed for Ruby)
495 main
['YACCFLAGS'] = '-d'
496 main
['YACCHXXFILESUFFIX'] = '.hh'
498 # Do this after we save setting back, or else we'll tack on an
499 # extra 'qdo' every time we run scons.
501 main
['CC'] = main
['BATCH_CMD'] + ' ' + main
['CC']
502 main
['CXX'] = main
['BATCH_CMD'] + ' ' + main
['CXX']
503 main
['AS'] = main
['BATCH_CMD'] + ' ' + main
['AS']
504 main
['AR'] = main
['BATCH_CMD'] + ' ' + main
['AR']
505 main
['RANLIB'] = main
['BATCH_CMD'] + ' ' + main
['RANLIB']
507 if sys
.platform
== 'cygwin':
508 # cygwin has some header file issues...
509 main
.Append(CCFLAGS
=["-Wno-uninitialized"])
512 have_pkg_config
= readCommand(['pkg-config', '--version'], exception
='')
514 # Check for the protobuf compiler
516 main
['HAVE_PROTOC'] = True
517 protoc_version
= readCommand([main
['PROTOC'], '--version']).split()
519 # First two words should be "libprotoc x.y.z"
520 if len(protoc_version
) < 2 or protoc_version
[0] != 'libprotoc':
521 warning('Protocol buffer compiler (protoc) not found.\n'
522 'Please install protobuf-compiler for tracing support.')
523 main
['HAVE_PROTOC'] = False
525 # Based on the availability of the compress stream wrappers,
527 min_protoc_version
= '2.1.0'
528 if compareVersions(protoc_version
[1], min_protoc_version
) < 0:
529 warning('protoc version', min_protoc_version
,
530 'or newer required.\n'
531 'Installed version:', protoc_version
[1])
532 main
['HAVE_PROTOC'] = False
534 # Attempt to determine the appropriate include path and
535 # library path using pkg-config, that means we also need to
536 # check for pkg-config. Note that it is possible to use
537 # protobuf without the involvement of pkg-config. Later on we
538 # check go a library config check and at that point the test
539 # will fail if libprotobuf cannot be found.
542 # Attempt to establish what linking flags to add for
546 'pkg-config --cflags --libs-only-L protobuf')
548 warning('pkg-config could not get protobuf flags.')
549 except Exception as e
:
550 warning('While checking protoc version:', str(e
))
551 main
['HAVE_PROTOC'] = False
553 # Check for 'timeout' from GNU coreutils. If present, regressions will
554 # be run with a time limit. We require version 8.13 since we rely on
555 # support for the '--foreground' option.
556 if sys
.platform
.startswith('freebsd'):
557 timeout_lines
= readCommand(['gtimeout', '--version'],
558 exception
='').splitlines()
560 timeout_lines
= readCommand(['timeout', '--version'],
561 exception
='').splitlines()
562 # Get the first line and tokenize it
563 timeout_version
= timeout_lines
[0].split() if timeout_lines
else []
564 main
['TIMEOUT'] = timeout_version
and \
565 compareVersions(timeout_version
[-1], '8.13') >= 0
567 # Add a custom Check function to test for structure members.
568 def CheckMember(context
, include
, decl
, member
, include_quotes
="<>"):
569 context
.Message("Checking for member %s in %s..." %
575 (void)test.%(member)s;
578 """ % { "header" : include_quotes
[0] + include
+ include_quotes
[1],
583 ret
= context
.TryCompile(text
, extension
=".cc")
587 # Platform-specific configuration. Note again that we assume that all
588 # builds under a given build root run on the same host platform.
589 conf
= Configure(main
,
590 conf_dir
= joinpath(build_root
, '.scons_config'),
591 log_file
= joinpath(build_root
, 'scons_config.log'),
593 'CheckMember' : CheckMember
,
596 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
599 uname
= platform
.uname()
600 if uname
[0] == 'Darwin' and compareVersions(uname
[2], '9.0.0') >= 0:
601 if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
602 main
.Append(CCFLAGS
=['-arch', 'x86_64'])
603 main
.Append(CFLAGS
=['-arch', 'x86_64'])
604 main
.Append(LINKFLAGS
=['-arch', 'x86_64'])
605 main
.Append(ASFLAGS
=['-arch', 'x86_64'])
609 # Recent versions of scons substitute a "Null" object for Configure()
610 # when configuration isn't necessary, e.g., if the "--help" option is
611 # present. Unfortuantely this Null object always returns false,
612 # breaking all our configuration checks. We replace it with our own
613 # more optimistic null object that returns True instead.
615 def NullCheck(*args
, **kwargs
):
619 def __init__(self
, env
):
623 def __getattr__(self
, mname
):
626 conf
= NullConf(main
)
628 # Cache build files in the supplied directory.
629 if main
['M5_BUILD_CACHE']:
630 print('Using build cache located at', main
['M5_BUILD_CACHE'])
631 CacheDir(main
['M5_BUILD_CACHE'])
633 main
['USE_PYTHON'] = not GetOption('without_python')
634 if main
['USE_PYTHON']:
635 # Find Python include and library directories for embedding the
636 # interpreter. We rely on python-config to resolve the appropriate
637 # includes and linker flags. ParseConfig does not seem to understand
638 # the more exotic linker flags such as -Xlinker and -export-dynamic so
639 # we add them explicitly below. If you want to link in an alternate
640 # version of python, see above for instructions on how to invoke
641 # scons with the appropriate PATH set.
643 python_config
= main
.Detect(main
['PYTHON_CONFIG'])
644 if python_config
is None:
645 error("Can't find a suitable python-config, tried %s" % \
646 main
['PYTHON_CONFIG'])
648 print("Info: Using Python config: %s" % (python_config
, ))
649 py_includes
= readCommand([python_config
, '--includes'],
650 exception
='').split()
651 py_includes
= list(filter(
652 lambda s
: match(r
'.*\/include\/.*',s
), py_includes
))
653 # Strip the -I from the include folders before adding them to the
655 py_includes
= list(map(
656 lambda s
: s
[2:] if s
.startswith('-I') else s
, py_includes
))
657 main
.Append(CPPPATH
=py_includes
)
659 # Read the linker flags and split them into libraries and other link
660 # flags. The libraries are added later through the call the CheckLib.
661 # Note: starting in Python 3.8 the --embed flag is required to get the
662 # -lpython3.8 linker flag
663 retcode
, cmd_stdout
= readCommandWithReturn(
664 [python_config
, '--ldflags', '--embed'], exception
='')
666 # If --embed isn't detected then we're running python <3.8
667 retcode
, cmd_stdout
= readCommandWithReturn(
668 [python_config
, '--ldflags'], exception
='')
670 # Checking retcode again
672 error("Failing on python-config --ldflags command")
674 py_ld_flags
= cmd_stdout
.split()
677 for lib
in py_ld_flags
:
678 if not lib
.startswith('-l'):
679 main
.Append(LINKFLAGS
=[lib
])
682 if lib
not in py_libs
:
685 # verify that this stuff works
686 if not conf
.CheckHeader('Python.h', '<>'):
687 error("Check failed for Python.h header in",
688 ' '.join(py_includes
), "\n"
689 "Two possible reasons:\n"
690 "1. Python headers are not installed (You can install the "
691 "package python-dev on Ubuntu and RedHat)\n"
692 "2. SCons is using a wrong C compiler. This can happen if "
693 "CC has the wrong value.\n"
694 "CC = %s" % main
['CC'])
697 if not conf
.CheckLib(lib
):
698 error("Can't find library %s required by python." % lib
)
700 main
.Prepend(CPPPATH
=Dir('ext/pybind11/include/'))
701 # Bare minimum environment that only includes python
702 marshal_env
= main
.Clone()
703 marshal_env
.Append(CCFLAGS
='$MARSHAL_CCFLAGS_EXTRA')
704 marshal_env
.Append(LINKFLAGS
='$MARSHAL_LDFLAGS_EXTRA')
706 # On Solaris you need to use libsocket for socket ops
707 if not conf
.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
708 if not conf
.CheckLibWithHeader('socket', 'sys/socket.h',
709 'C++', 'accept(0,0,0);'):
710 error("Can't find library with socket calls (e.g. accept()).")
712 # Check for zlib. If the check passes, libz will be automatically
713 # added to the LIBS environment variable.
714 if not conf
.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
715 error('Did not find needed zlib compression library '
716 'and/or zlib.h header file.\n'
717 'Please install zlib and try again.')
719 if not conf
.CheckLibWithHeader('elf', 'gelf.h', 'C++',
720 'elf_version(EV_CURRENT);'):
721 error('Did not find ELF access library libelf')
723 # If we have the protobuf compiler, also make sure we have the
724 # development libraries. If the check passes, libprotobuf will be
725 # automatically added to the LIBS environment variable. After
726 # this, we can use the HAVE_PROTOBUF flag to determine if we have
727 # got both protoc and libprotobuf available.
728 main
['HAVE_PROTOBUF'] = main
['HAVE_PROTOC'] and \
729 conf
.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
730 'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
732 # Valgrind gets much less confused if you tell it when you're using
733 # alternative stacks.
734 main
['HAVE_VALGRIND'] = conf
.CheckCHeader('valgrind/valgrind.h')
736 # If we have the compiler but not the library, print another warning.
737 if main
['HAVE_PROTOC'] and not main
['HAVE_PROTOBUF']:
738 warning('Did not find protocol buffer library and/or headers.\n'
739 'Please install libprotobuf-dev for tracing support.')
743 conf
.CheckLibWithHeader(None, 'time.h', 'C',
744 'clock_nanosleep(0,0,NULL,NULL);') or \
745 conf
.CheckLibWithHeader('rt', 'time.h', 'C',
746 'clock_nanosleep(0,0,NULL,NULL);')
748 have_posix_timers
= \
749 conf
.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
750 'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
752 if not GetOption('without_tcmalloc'):
753 if conf
.CheckLib('tcmalloc'):
754 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
755 elif conf
.CheckLib('tcmalloc_minimal'):
756 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
758 warning("You can get a 12% performance improvement by "
759 "installing tcmalloc (libgoogle-perftools-dev package "
760 "on Ubuntu or RedHat).")
763 # Detect back trace implementations. The last implementation in the
764 # list will be used by default.
765 backtrace_impls
= [ "none" ]
767 backtrace_checker
= 'char temp;' + \
768 ' backtrace_symbols_fd((void*)&temp, 0, 0);'
769 if conf
.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker
):
770 backtrace_impls
.append("glibc")
771 elif conf
.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
773 # NetBSD and FreeBSD need libexecinfo.
774 backtrace_impls
.append("glibc")
775 main
.Append(LIBS
=['execinfo'])
777 if backtrace_impls
[-1] == "none":
778 default_backtrace_impl
= "none"
779 warning("No suitable back trace implementation found.")
781 if not have_posix_clock
:
782 warning("Can't find library for POSIX clocks.")
784 # Check for <fenv.h> (C99 FP environment control)
785 have_fenv
= conf
.CheckHeader('fenv.h', '<>')
787 warning("Header file <fenv.h> not found.\n"
788 "This host has no IEEE FP rounding mode control.")
790 # Check for <png.h> (libpng library needed if wanting to dump
791 # frame buffer image in png format)
792 have_png
= conf
.CheckHeader('png.h', '<>')
794 warning("Header file <png.h> not found.\n"
795 "This host has no libpng library.\n"
796 "Disabling support for PNG framebuffers.")
798 # Check if we should enable KVM-based hardware virtualization. The API
799 # we rely on exists since version 2.6.36 of the kernel, but somehow
800 # the KVM_API_VERSION does not reflect the change. We test for one of
801 # the types as a fall back.
802 have_kvm
= conf
.CheckHeader('linux/kvm.h', '<>')
804 print("Info: Compatible header file <linux/kvm.h> not found, "
805 "disabling KVM support.")
807 # Check if the TUN/TAP driver is available.
808 have_tuntap
= conf
.CheckHeader('linux/if_tun.h', '<>')
810 print("Info: Compatible header file <linux/if_tun.h> not found.")
812 # x86 needs support for xsave. We test for the structure here since we
813 # won't be able to run new tests by the time we know which ISA we're
815 have_kvm_xsave
= conf
.CheckTypeSize('struct kvm_xsave',
816 '#include <linux/kvm.h>') != 0
818 # Check if the requested target ISA is compatible with the host
819 def is_isa_kvm_compatible(isa
):
822 host_isa
= platform
.machine()
824 warning("Failed to determine host ISA.")
827 if not have_posix_timers
:
828 warning("Can not enable KVM, host seems to lack support "
833 return host_isa
in ( "armv7l", "aarch64" )
835 if host_isa
!= "x86_64":
838 if not have_kvm_xsave
:
839 warning("KVM on x86 requires xsave support in kernel headers.")
847 # Check if the exclude_host attribute is available. We want this to
848 # get accurate instruction counts in KVM.
849 main
['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf
.CheckMember(
850 'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
854 conf
.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
855 'H5Fcreate("", 0, 0, 0);') and \
856 conf
.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
857 'H5::H5File("", 0);')
859 def check_hdf5_pkg(name
):
860 print("Checking for %s using pkg-config..." % name
, end
="")
861 if not have_pkg_config
:
862 print(" pkg-config not found")
866 main
.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name
)
873 # Check if there is a pkg-config configuration for hdf5. If we find
874 # it, setup the environment to enable linking and header inclusion. We
875 # don't actually try to include any headers or link with hdf5 at this
877 if not check_hdf5_pkg('hdf5-serial'):
878 check_hdf5_pkg('hdf5')
880 # Check if the HDF5 libraries can be found. This check respects the
881 # include path and library path provided by pkg-config. We perform
882 # this check even if there isn't a pkg-config configuration for hdf5
883 # since some installations don't use pkg-config.
884 have_hdf5
= check_hdf5()
886 print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
887 print(" HDF5 support.")
889 ######################################################################
891 # Finish the configuration
895 ######################################################################
897 # Collect all non-global variables
900 # Define the universe of supported ISAs
902 all_gpu_isa_list
= [ ]
903 Export('all_isa_list')
904 Export('all_gpu_isa_list')
906 class CpuModel(object):
907 '''The CpuModel class encapsulates everything the ISA parser needs to
908 know about a particular CPU model.'''
910 # Dict of available CPU model objects. Accessible as CpuModel.dict.
913 # Constructor. Automatically adds models to CpuModel.dict.
914 def __init__(self
, name
, default
=False):
915 self
.name
= name
# name of model
917 # This cpu is enabled by default
918 self
.default
= default
921 if name
in CpuModel
.dict:
922 raise AttributeError("CpuModel '%s' already registered" % name
)
923 CpuModel
.dict[name
] = self
927 # Sticky variables get saved in the variables file so they persist from
928 # one invocation to the next (unless overridden, in which case the new
929 # value becomes sticky).
930 sticky_vars
= Variables(args
=ARGUMENTS
)
931 Export('sticky_vars')
933 # Sticky variables that should be exported
935 Export('export_vars')
939 Export('all_protocols')
941 Export('protocol_dirs')
943 Export('slicc_includes')
945 # Walk the tree and execute all SConsopts scripts that wil add to the
947 if GetOption('verbose'):
948 print("Reading SConsopts")
949 for bdir
in [ base_dir
] + extras_dir_list
:
951 error("Directory '%s' does not exist." % bdir
)
952 for root
, dirs
, files
in os
.walk(bdir
):
953 if 'SConsopts' in files
:
954 if GetOption('verbose'):
955 print("Reading", joinpath(root
, 'SConsopts'))
956 SConscript(joinpath(root
, 'SConsopts'))
959 all_gpu_isa_list
.sort()
961 sticky_vars
.AddVariables(
962 EnumVariable('TARGET_ISA', 'Target ISA', 'null', all_isa_list
),
963 EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'gcn3', all_gpu_isa_list
),
964 ListVariable('CPU_MODELS', 'CPU models',
965 sorted(n
for n
,m
in CpuModel
.dict.items() if m
.default
),
966 sorted(CpuModel
.dict.keys())),
967 BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
969 BoolVariable('USE_SSE2',
970 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
972 BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock
),
973 BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv
),
974 BoolVariable('USE_PNG', 'Enable support for PNG images', have_png
),
975 BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
977 BoolVariable('USE_TUNTAP',
978 'Enable using a tap device to bridge to the host network',
980 BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
981 EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
983 EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
984 backtrace_impls
[-1], backtrace_impls
),
985 ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
987 BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5
),
990 # These variables get exported to #defines in config/*.hh (see src/SConscript).
991 export_vars
+= ['USE_FENV', 'TARGET_ISA', 'TARGET_GPU_ISA',
992 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP', 'PROTOCOL',
993 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
994 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
995 'NUMBER_BITS_PER_SET', 'USE_HDF5']
997 ###################################################
999 # Define a SCons builder for configuration flag headers.
1001 ###################################################
1003 # This function generates a config header file that #defines the
1004 # variable symbol to the current variable setting (0 or 1). The source
1005 # operands are the name of the variable and a Value node containing the
1006 # value of the variable.
1007 def build_config_file(target
, source
, env
):
1008 (variable
, value
) = [s
.get_contents().decode('utf-8') for s
in source
]
1009 with
open(str(target
[0]), 'w') as f
:
1010 print('#define', variable
, value
, file=f
)
1013 # Combine the two functions into a scons Action object.
1014 config_action
= MakeAction(build_config_file
, Transform("CONFIG H", 2))
1016 # The emitter munges the source & target node lists to reflect what
1017 # we're really doing.
1018 def config_emitter(target
, source
, env
):
1019 # extract variable name from Builder arg
1020 variable
= str(target
[0])
1021 # True target is config header file
1022 target
= joinpath('config', variable
.lower() + '.hh')
1024 if isinstance(val
, bool):
1025 # Force value to 0/1
1027 elif isinstance(val
, str):
1028 val
= '"' + val
+ '"'
1030 # Sources are variable name & value (packaged in SCons Value nodes)
1031 return ([target
], [Value(variable
), Value(val
)])
1033 config_builder
= Builder(emitter
= config_emitter
, action
= config_action
)
1035 main
.Append(BUILDERS
= { 'ConfigFile' : config_builder
})
1037 ###################################################
1039 # Builders for static and shared partially linked object files.
1041 ###################################################
1043 partial_static_builder
= Builder(action
=SCons
.Defaults
.LinkAction
,
1044 src_suffix
='$OBJSUFFIX',
1045 src_builder
=['StaticObject', 'Object'],
1046 LINKFLAGS
='$PLINKFLAGS',
1049 def partial_shared_emitter(target
, source
, env
):
1051 tgt
.attributes
.shared
= 1
1052 return (target
, source
)
1053 partial_shared_builder
= Builder(action
=SCons
.Defaults
.ShLinkAction
,
1054 emitter
=partial_shared_emitter
,
1055 src_suffix
='$SHOBJSUFFIX',
1056 src_builder
='SharedObject',
1057 SHLINKFLAGS
='$PSHLINKFLAGS',
1060 main
.Append(BUILDERS
= { 'PartialShared' : partial_shared_builder
,
1061 'PartialStatic' : partial_static_builder
})
1063 def add_local_rpath(env
, *targets
):
1064 '''Set up an RPATH for a library which lives in the build directory.
1066 The construction environment variable BIN_RPATH_PREFIX should be set to
1067 the relative path of the build directory starting from the location of the
1069 for target
in targets
:
1070 target
= env
.Entry(target
)
1071 if not isinstance(target
, SCons
.Node
.FS
.Dir
):
1073 relpath
= os
.path
.relpath(target
.abspath
, env
['BUILDDIR'])
1076 '${BIN_RPATH_PREFIX}',
1079 env
.Append(RPATH
=[env
.Literal(os
.path
.join(*components
))])
1081 if sys
.platform
!= "darwin":
1082 main
.Append(LINKFLAGS
=Split('-z origin'))
1084 main
.AddMethod(add_local_rpath
, 'AddLocalRPATH')
1086 # builds in ext are shared across all configs in the build root.
1087 ext_dir
= abspath(joinpath(str(main
.root
), 'ext'))
1089 for root
, dirs
, files
in os
.walk(ext_dir
):
1090 if 'SConscript' in files
:
1091 build_dir
= os
.path
.relpath(root
, ext_dir
)
1092 ext_build_dirs
.append(build_dir
)
1093 main
.SConscript(joinpath(root
, 'SConscript'),
1094 variant_dir
=joinpath(build_root
, build_dir
))
1096 gdb_xml_dir
= joinpath(ext_dir
, 'gdb-xml')
1097 Export('gdb_xml_dir')
1099 ###################################################
1101 # This builder and wrapper method are used to set up a directory with
1102 # switching headers. Those are headers which are in a generic location and
1103 # that include more specific headers from a directory chosen at build time
1104 # based on the current build settings.
1106 ###################################################
1108 def build_switching_header(target
, source
, env
):
1109 path
= str(target
[0])
1110 subdir
= str(source
[0])
1111 dp
, fp
= os
.path
.split(path
)
1112 dp
= os
.path
.relpath(os
.path
.realpath(dp
),
1113 os
.path
.realpath(env
['BUILDDIR']))
1114 with
open(path
, 'w') as hdr
:
1115 print('#include "%s/%s/%s"' % (dp
, subdir
, fp
), file=hdr
)
1117 switching_header_action
= MakeAction(build_switching_header
,
1118 Transform('GENERATE'))
1120 switching_header_builder
= Builder(action
=switching_header_action
,
1121 source_factory
=Value
,
1124 main
.Append(BUILDERS
= { 'SwitchingHeader': switching_header_builder
})
1126 def switching_headers(self
, headers
, source
):
1127 for header
in headers
:
1128 self
.SwitchingHeader(header
, source
)
1130 main
.AddMethod(switching_headers
, 'SwitchingHeaders')
1132 ###################################################
1134 # Define build environments for selected configurations.
1136 ###################################################
1138 for variant_path
in variant_paths
:
1139 if not GetOption('silent'):
1140 print("Building in", variant_path
)
1142 # Make a copy of the build-root environment to use for this config.
1144 env
['BUILDDIR'] = variant_path
1146 # variant_dir is the tail component of build path, and is used to
1147 # determine the build parameters (e.g., 'X86')
1148 (build_root
, variant_dir
) = splitpath(variant_path
)
1150 # Set env variables according to the build directory config.
1151 sticky_vars
.files
= []
1152 # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1153 # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1154 # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1155 current_vars_file
= joinpath(build_root
, 'variables', variant_dir
)
1156 if isfile(current_vars_file
):
1157 sticky_vars
.files
.append(current_vars_file
)
1158 if not GetOption('silent'):
1159 print("Using saved variables file %s" % current_vars_file
)
1160 elif variant_dir
in ext_build_dirs
:
1161 # Things in ext are built without a variant directory.
1164 # Build dir-specific variables file doesn't exist.
1166 # Make sure the directory is there so we can create it later
1167 opt_dir
= dirname(current_vars_file
)
1168 if not isdir(opt_dir
):
1171 # Get default build variables from source tree. Variables are
1172 # normally determined by name of $VARIANT_DIR, but can be
1173 # overridden by '--default=' arg on command line.
1174 default
= GetOption('default')
1175 opts_dir
= joinpath(main
.root
.abspath
, 'build_opts')
1177 default_vars_files
= [joinpath(build_root
, 'variables', default
),
1178 joinpath(opts_dir
, default
)]
1180 default_vars_files
= [joinpath(opts_dir
, variant_dir
)]
1181 existing_files
= list(filter(isfile
, default_vars_files
))
1183 default_vars_file
= existing_files
[0]
1184 sticky_vars
.files
.append(default_vars_file
)
1185 print("Variables file %s not found,\n using defaults in %s"
1186 % (current_vars_file
, default_vars_file
))
1188 error("Cannot find variables file %s or default file(s) %s"
1189 % (current_vars_file
, ' or '.join(default_vars_files
)))
1192 # Apply current variable settings to env
1193 sticky_vars
.Update(env
)
1196 Build variables for {dir}:
1198 '''.format(dir=variant_dir
, help=sticky_vars
.GenerateHelpText(env
)),
1201 # Process variable settings.
1203 if not have_fenv
and env
['USE_FENV']:
1204 warning("<fenv.h> not available; forcing USE_FENV to False in",
1206 env
['USE_FENV'] = False
1208 if not env
['USE_FENV']:
1209 warning("No IEEE FP rounding mode control in", variant_dir
+ ".\n"
1210 "FP results may deviate slightly from other platforms.")
1212 if not have_png
and env
['USE_PNG']:
1213 warning("<png.h> not available; forcing USE_PNG to False in",
1215 env
['USE_PNG'] = False
1218 env
.Append(LIBS
=['png'])
1221 env
.Append(LIBS
=['efence'])
1225 warning("Can not enable KVM, host seems to lack KVM support")
1226 env
['USE_KVM'] = False
1227 elif not is_isa_kvm_compatible(env
['TARGET_ISA']):
1228 print("Info: KVM support disabled due to unsupported host and "
1229 "target ISA combination")
1230 env
['USE_KVM'] = False
1232 if env
['USE_TUNTAP']:
1234 warning("Can't connect EtherTap with a tap device.")
1235 env
['USE_TUNTAP'] = False
1237 if env
['BUILD_GPU']:
1238 env
.Append(CPPDEFINES
=['BUILD_GPU'])
1240 # Warn about missing optional functionality
1242 if not main
['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1243 warning("perf_event headers lack support for the exclude_host "
1244 "attribute. KVM instruction counts will be inaccurate.")
1246 # Save sticky variable settings back to current variables file
1247 sticky_vars
.Save(current_vars_file
, env
)
1250 env
.Append(CCFLAGS
=['-msse2'])
1252 env
.Append(CCFLAGS
='$CCFLAGS_EXTRA')
1253 env
.Append(LINKFLAGS
='$LDFLAGS_EXTRA')
1255 # The src/SConscript file sets up the build rules in 'env' according
1256 # to the configured variables. It returns a list of environments,
1257 # one for each variant build (debug, opt, etc.)
1258 SConscript('src/SConscript', variant_dir
=variant_path
,
1259 exports
=['env', 'marshal_env'])
1261 atexit
.register(summarize_warnings
)