3 # Copyright (c) 2013, 2015-2019 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 # Authors: Steve Reinhardt
46 ###################################################
48 # SCons top-level build description (SConstruct) file.
50 # While in this directory ('gem5'), just type 'scons' to build the default
51 # configuration (see below), or type 'scons build/<CONFIG>/<binary>'
52 # to build some other configuration (e.g., 'build/ALPHA/gem5.opt' for
53 # the optimized full-system version).
55 # You can build gem5 in a different directory as long as there is a
56 # 'build/<CONFIG>' somewhere along the target path. The build system
57 # expects that all configs under the same build directory are being
58 # built for the same host system.
62 # The following two commands are equivalent. The '-u' option tells
63 # scons to search up the directory tree for this SConstruct file.
64 # % cd <path-to-src>/gem5 ; scons build/ALPHA/gem5.debug
65 # % cd <path-to-src>/gem5/build/ALPHA; scons -u gem5.debug
67 # The following two commands are equivalent and demonstrate building
68 # in a directory outside of the source tree. The '-C' option tells
69 # scons to chdir to the specified directory to find this SConstruct
71 # % cd <path-to-src>/gem5 ; scons /local/foo/build/ALPHA/gem5.debug
72 # % cd /local/foo/build/ALPHA; scons -C <path-to-src>/gem5 gem5.debug
74 # You can use 'scons -H' to print scons options. If you're in this
75 # 'gem5' directory (or use -u or -C to tell scons where to find this
76 # file), you can use 'scons -h' to print all the gem5-specific build
79 ###################################################
81 from __future__
import print_function
83 # Global Python includes
91 from os
import mkdir
, environ
92 from os
.path
import abspath
, basename
, dirname
, expanduser
, normpath
93 from os
.path
import exists
, isdir
, isfile
94 from os
.path
import join
as joinpath
, split
as splitpath
102 from m5
.util
import compareVersions
, readCommand
113 # There's a bug in scons in that (1) by default, the help texts from
114 # AddOption() are supposed to be displayed when you type 'scons -h'
115 # and (2) you can override the help displayed by 'scons -h' using the
116 # Help() function, but these two features are incompatible: once
117 # you've overridden the help text using Help(), there's no way to get
118 # at the help texts from AddOptions. See:
119 # http://scons.tigris.org/issues/show_bug.cgi?id=2356
120 # http://scons.tigris.org/issues/show_bug.cgi?id=2611
121 # This hack lets us extract the help text from AddOptions and
122 # re-inject it via Help(). Ideally someday this bug will be fixed and
123 # we can just use AddOption directly.
124 def AddLocalOption(*args
, **kwargs
):
127 help = " " + ", ".join(args
)
130 if length
>= col_width
:
131 help += "\n" + " " * col_width
133 help += " " * (col_width
- length
)
134 help += kwargs
["help"]
135 help_texts
["options"] += help + "\n"
137 AddOption(*args
, **kwargs
)
139 AddLocalOption('--colors', dest
='use_colors', action
='store_true',
140 help="Add color to abbreviated scons output")
141 AddLocalOption('--no-colors', dest
='use_colors', action
='store_false',
142 help="Don't add color to abbreviated scons output")
143 AddLocalOption('--with-cxx-config', dest
='with_cxx_config',
145 help="Build with support for C++-based configuration")
146 AddLocalOption('--default', dest
='default', type='string', action
='store',
147 help='Override which build_opts file to use for defaults')
148 AddLocalOption('--ignore-style', dest
='ignore_style', action
='store_true',
149 help='Disable style checking hooks')
150 AddLocalOption('--gold-linker', dest
='gold_linker', action
='store_true',
151 help='Use the gold linker')
152 AddLocalOption('--no-lto', dest
='no_lto', action
='store_true',
153 help='Disable Link-Time Optimization for fast')
154 AddLocalOption('--force-lto', dest
='force_lto', action
='store_true',
155 help='Use Link-Time Optimization instead of partial linking' +
156 ' when the compiler doesn\'t support using them together.')
157 AddLocalOption('--update-ref', dest
='update_ref', action
='store_true',
158 help='Update test reference outputs')
159 AddLocalOption('--verbose', dest
='verbose', action
='store_true',
160 help='Print full tool command lines')
161 AddLocalOption('--without-python', dest
='without_python',
163 help='Build without Python configuration support')
164 AddLocalOption('--without-tcmalloc', dest
='without_tcmalloc',
166 help='Disable linking against tcmalloc')
167 AddLocalOption('--with-ubsan', dest
='with_ubsan', action
='store_true',
168 help='Build with Undefined Behavior Sanitizer if available')
169 AddLocalOption('--with-asan', dest
='with_asan', action
='store_true',
170 help='Build with Address Sanitizer if available')
172 from gem5_scons
import Transform
, error
, warning
174 if GetOption('no_lto') and GetOption('force_lto'):
175 error('--no-lto and --force-lto are mutually exclusive')
177 ########################################################################
179 # Set up the main build environment.
181 ########################################################################
185 from gem5_scons
.util
import get_termcap
186 termcap
= get_termcap()
188 main_dict_keys
= main
.Dictionary().keys()
190 # Check that we have a C/C++ compiler
191 if not ('CC' in main_dict_keys
and 'CXX' in main_dict_keys
):
192 error("No C++ compiler installed (package g++ on Ubuntu and RedHat)")
194 ###################################################
196 # Figure out which configurations to set up based on the path(s) of
199 ###################################################
201 # Find default configuration & binary.
202 Default(environ
.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
204 # helper function: find last occurrence of element in list
205 def rfind(l
, elt
, offs
= -1):
206 for i
in range(len(l
)+offs
, 0, -1):
209 raise ValueError, "element not found"
211 # Take a list of paths (or SCons Nodes) and return a list with all
212 # paths made absolute and ~-expanded. Paths will be interpreted
213 # relative to the launch directory unless a different root is provided
214 def makePathListAbsolute(path_list
, root
=GetLaunchDir()):
215 return [abspath(joinpath(root
, expanduser(str(p
))))
218 def find_first_prog(prog_names
):
219 """Find the absolute path to the first existing binary in prog_names"""
221 if not isinstance(prog_names
, (list, tuple)):
222 prog_names
= [ prog_names
]
231 # Each target must have 'build' in the interior of the path; the
232 # directory below this will determine the build parameters. For
233 # example, for target 'foo/bar/build/ALPHA_SE/arch/alpha/blah.do' we
234 # recognize that ALPHA_SE specifies the configuration because it
235 # follow 'build' in the build path.
237 # The funky assignment to "[:]" is needed to replace the list contents
238 # in place rather than reassign the symbol to a new list, which
239 # doesn't work (obviously!).
240 BUILD_TARGETS
[:] = makePathListAbsolute(BUILD_TARGETS
)
242 # Generate a list of the unique build roots and configs that the
243 # collected targets reference.
246 for t
in BUILD_TARGETS
:
247 path_dirs
= t
.split('/')
249 build_top
= rfind(path_dirs
, 'build', -2)
251 error("No non-leaf 'build' dir found on target path.", t
)
252 this_build_root
= joinpath('/',*path_dirs
[:build_top
+1])
254 build_root
= this_build_root
256 if this_build_root
!= build_root
:
257 error("build targets not under same build root\n"
258 " %s\n %s" % (build_root
, this_build_root
))
259 variant_path
= joinpath('/',*path_dirs
[:build_top
+2])
260 if variant_path
not in variant_paths
:
261 variant_paths
.append(variant_path
)
263 # Make sure build_root exists (might not if this is the first build there)
264 if not isdir(build_root
):
266 main
['BUILDROOT'] = build_root
270 main
.SConsignFile(joinpath(build_root
, "sconsign"))
272 # Default duplicate option is to use hard links, but this messes up
273 # when you use emacs to edit a file in the target dir, as emacs moves
274 # file to file~ then copies to file, breaking the link. Symbolic
275 # (soft) links work better.
276 main
.SetOption('duplicate', 'soft-copy')
279 # Set up global sticky variables... these are common to an entire build
280 # tree (not specific to a particular build like ALPHA_SE)
283 global_vars_file
= joinpath(build_root
, 'variables.global')
285 global_vars
= Variables(global_vars_file
, args
=ARGUMENTS
)
287 global_vars
.AddVariables(
288 ('CC', 'C compiler', environ
.get('CC', main
['CC'])),
289 ('CXX', 'C++ compiler', environ
.get('CXX', main
['CXX'])),
290 ('CCFLAGS_EXTRA', 'Extra C and C++ compiler flags', ''),
291 ('LDFLAGS_EXTRA', 'Extra linker flags', ''),
292 ('PYTHON_CONFIG', 'Python config binary to use',
293 [ 'python2.7-config', 'python-config' ]),
294 ('PROTOC', 'protoc tool', environ
.get('PROTOC', 'protoc')),
295 ('BATCH', 'Use batch pool for build and tests', False),
296 ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
297 ('M5_BUILD_CACHE', 'Cache built objects in this directory', False),
298 ('EXTRAS', 'Add extra directories to the compilation', '')
301 # Update main environment with values from ARGUMENTS & global_vars_file
302 global_vars
.Update(main
)
303 help_texts
["global_vars"] += global_vars
.GenerateHelpText(main
)
305 # Save sticky variable settings back to current variables file
306 global_vars
.Save(global_vars_file
, main
)
308 # Parse EXTRAS variable to build list of all directories where we're
309 # look for sources etc. This list is exported as extras_dir_list.
310 base_dir
= main
.srcdir
.abspath
312 extras_dir_list
= makePathListAbsolute(main
['EXTRAS'].split(':'))
317 Export('extras_dir_list')
319 # the ext directory should be on the #includes path
320 main
.Append(CPPPATH
=[Dir('ext')])
322 # Add shared top-level headers
323 main
.Prepend(CPPPATH
=Dir('include'))
325 if GetOption('verbose'):
326 def MakeAction(action
, string
, *args
, **kwargs
):
327 return Action(action
, *args
, **kwargs
)
330 main
['CCCOMSTR'] = Transform("CC")
331 main
['CXXCOMSTR'] = Transform("CXX")
332 main
['ASCOMSTR'] = Transform("AS")
333 main
['ARCOMSTR'] = Transform("AR", 0)
334 main
['LINKCOMSTR'] = Transform("LINK", 0)
335 main
['SHLINKCOMSTR'] = Transform("SHLINK", 0)
336 main
['RANLIBCOMSTR'] = Transform("RANLIB", 0)
337 main
['M4COMSTR'] = Transform("M4")
338 main
['SHCCCOMSTR'] = Transform("SHCC")
339 main
['SHCXXCOMSTR'] = Transform("SHCXX")
342 # Initialize the Link-Time Optimization (LTO) flags
343 main
['LTO_CCFLAGS'] = []
344 main
['LTO_LDFLAGS'] = []
346 # According to the readme, tcmalloc works best if the compiler doesn't
347 # assume that we're using the builtin malloc and friends. These flags
348 # are compiler-specific, so we need to set them after we detect which
349 # compiler we're using.
350 main
['TCMALLOC_CCFLAGS'] = []
352 CXX_version
= readCommand([main
['CXX'],'--version'], exception
=False)
353 CXX_V
= readCommand([main
['CXX'],'-V'], exception
=False)
355 main
['GCC'] = CXX_version
and CXX_version
.find('g++') >= 0
356 main
['CLANG'] = CXX_version
and CXX_version
.find('clang') >= 0
357 if main
['GCC'] + main
['CLANG'] > 1:
358 error('Two compilers enabled at once?')
360 # Set up default C++ compiler flags
361 if main
['GCC'] or main
['CLANG']:
362 # As gcc and clang share many flags, do the common parts here
363 main
.Append(CCFLAGS
=['-pipe'])
364 main
.Append(CCFLAGS
=['-fno-strict-aliasing'])
365 # Enable -Wall and -Wextra and then disable the few warnings that
366 # we consistently violate
367 main
.Append(CCFLAGS
=['-Wall', '-Wundef', '-Wextra',
368 '-Wno-sign-compare', '-Wno-unused-parameter'])
369 # We always compile using C++11
370 main
.Append(CXXFLAGS
=['-std=c++11'])
371 if sys
.platform
.startswith('freebsd'):
372 main
.Append(CCFLAGS
=['-I/usr/local/include'])
373 main
.Append(CXXFLAGS
=['-I/usr/local/include'])
375 main
['FILTER_PSHLINKFLAGS'] = lambda x
: str(x
).replace(' -shared', '')
376 main
['PSHLINKFLAGS'] = main
.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
377 if GetOption('gold_linker'):
378 main
.Append(LINKFLAGS
='-fuse-ld=gold')
379 main
['PLINKFLAGS'] = main
.subst('${LINKFLAGS}')
380 shared_partial_flags
= ['-r', '-nostdlib']
381 main
.Append(PSHLINKFLAGS
=shared_partial_flags
)
382 main
.Append(PLINKFLAGS
=shared_partial_flags
)
384 # Treat warnings as errors but white list some warnings that we
385 # want to allow (e.g., deprecation warnings).
386 main
.Append(CCFLAGS
=['-Werror',
387 '-Wno-error=deprecated-declarations',
388 '-Wno-error=deprecated',
392 "Don't know what compiler options to use for your compiler.",
393 "compiler: " + main
['CXX'],
394 "version: " + CXX_version
.replace('\n', '<nl>') if
395 CXX_version
else 'COMMAND NOT FOUND!',
396 "If you're trying to use a compiler other than GCC",
397 "or clang, there appears to be something wrong with your",
400 "If you are trying to use a compiler other than those listed",
401 "above you will need to ease fix SConstruct and ",
402 "src/SConscript to support that compiler."))
405 # Check for a supported version of gcc. >= 4.8 is chosen for its
406 # level of c++11 support. See
407 # http://gcc.gnu.org/projects/cxx0x.html for details.
408 gcc_version
= readCommand([main
['CXX'], '-dumpversion'], exception
=False)
409 if compareVersions(gcc_version
, "4.8") < 0:
410 error('gcc version 4.8 or newer required.\n'
411 'Installed version:', gcc_version
)
414 main
['GCC_VERSION'] = gcc_version
416 if compareVersions(gcc_version
, '4.9') >= 0:
417 # Incremental linking with LTO is currently broken in gcc versions
418 # 4.9 and above. A version where everything works completely hasn't
419 # yet been identified.
421 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
422 main
['BROKEN_INCREMENTAL_LTO'] = True
423 if compareVersions(gcc_version
, '6.0') >= 0:
424 # gcc versions 6.0 and greater accept an -flinker-output flag which
425 # selects what type of output the linker should generate. This is
426 # necessary for incremental lto to work, but is also broken in
427 # current versions of gcc. It may not be necessary in future
428 # versions. We add it here since it might be, and as a reminder that
429 # it exists. It's excluded if lto is being forced.
431 # https://gcc.gnu.org/gcc-6/changes.html
432 # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
433 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
434 if not GetOption('force_lto'):
435 main
.Append(PSHLINKFLAGS
='-flinker-output=rel')
436 main
.Append(PLINKFLAGS
='-flinker-output=rel')
438 # Make sure we warn if the user has requested to compile with the
439 # Undefined Benahvior Sanitizer and this version of gcc does not
441 if GetOption('with_ubsan') and compareVersions(gcc_version
, '4.9') < 0:
442 warning('UBSan is only supported using gcc 4.9 and later.')
444 disable_lto
= GetOption('no_lto')
445 if not disable_lto
and main
.get('BROKEN_INCREMENTAL_LTO', False) and \
446 not GetOption('force_lto'):
447 warning('Warning: Your compiler doesn\'t support incremental linking '
448 'and lto at the same time, so lto is being disabled. To force '
449 'lto on anyway, use the --force-lto option. That will disable '
453 # Add the appropriate Link-Time Optimization (LTO) flags
454 # unless LTO is explicitly turned off. Note that these flags
455 # are only used by the fast target.
457 # Pass the LTO flag when compiling to produce GIMPLE
458 # output, we merely create the flags here and only append
460 main
['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
462 # Use the same amount of jobs for LTO as we are running
464 main
['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
466 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin-malloc', '-fno-builtin-calloc',
467 '-fno-builtin-realloc', '-fno-builtin-free'])
469 # The address sanitizer is available for gcc >= 4.8
470 if GetOption('with_asan'):
471 if GetOption('with_ubsan') and \
472 compareVersions(main
['GCC_VERSION'], '4.9') >= 0:
473 main
.Append(CCFLAGS
=['-fsanitize=address,undefined',
474 '-fno-omit-frame-pointer'],
475 LINKFLAGS
='-fsanitize=address,undefined')
477 main
.Append(CCFLAGS
=['-fsanitize=address',
478 '-fno-omit-frame-pointer'],
479 LINKFLAGS
='-fsanitize=address')
480 # Only gcc >= 4.9 supports UBSan, so check both the version
481 # and the command-line option before adding the compiler and
483 elif GetOption('with_ubsan') and \
484 compareVersions(main
['GCC_VERSION'], '4.9') >= 0:
485 main
.Append(CCFLAGS
='-fsanitize=undefined')
486 main
.Append(LINKFLAGS
='-fsanitize=undefined')
489 # Check for a supported version of clang, >= 3.1 is needed to
490 # support similar features as gcc 4.8. See
491 # http://clang.llvm.org/cxx_status.html for details
492 clang_version_re
= re
.compile(".* version (\d+\.\d+)")
493 clang_version_match
= clang_version_re
.search(CXX_version
)
494 if (clang_version_match
):
495 clang_version
= clang_version_match
.groups()[0]
496 if compareVersions(clang_version
, "3.1") < 0:
497 error('clang version 3.1 or newer required.\n'
498 'Installed version:', clang_version
)
500 error('Unable to determine clang version.')
502 # clang has a few additional warnings that we disable, extraneous
503 # parantheses are allowed due to Ruby's printing of the AST,
504 # finally self assignments are allowed as the generated CPU code
506 main
.Append(CCFLAGS
=['-Wno-parentheses',
508 # Some versions of libstdc++ (4.8?) seem to
509 # use struct hash and class hash
511 '-Wno-mismatched-tags',
514 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin'])
516 # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
517 # opposed to libstdc++, as the later is dated.
518 if sys
.platform
== "darwin":
519 main
.Append(CXXFLAGS
=['-stdlib=libc++'])
520 main
.Append(LIBS
=['c++'])
522 # On FreeBSD we need libthr.
523 if sys
.platform
.startswith('freebsd'):
524 main
.Append(LIBS
=['thr'])
526 # We require clang >= 3.1, so there is no need to check any
528 if GetOption('with_ubsan'):
529 if GetOption('with_asan'):
530 main
.Append(CCFLAGS
=['-fsanitize=address,undefined',
531 '-fno-omit-frame-pointer'],
532 LINKFLAGS
='-fsanitize=address,undefined')
534 main
.Append(CCFLAGS
='-fsanitize=undefined',
535 LINKFLAGS
='-fsanitize=undefined')
537 elif GetOption('with_asan'):
538 main
.Append(CCFLAGS
=['-fsanitize=address',
539 '-fno-omit-frame-pointer'],
540 LINKFLAGS
='-fsanitize=address')
542 # Set up common yacc/bison flags (needed for Ruby)
543 main
['YACCFLAGS'] = '-d'
544 main
['YACCHXXFILESUFFIX'] = '.hh'
546 # Do this after we save setting back, or else we'll tack on an
547 # extra 'qdo' every time we run scons.
549 main
['CC'] = main
['BATCH_CMD'] + ' ' + main
['CC']
550 main
['CXX'] = main
['BATCH_CMD'] + ' ' + main
['CXX']
551 main
['AS'] = main
['BATCH_CMD'] + ' ' + main
['AS']
552 main
['AR'] = main
['BATCH_CMD'] + ' ' + main
['AR']
553 main
['RANLIB'] = main
['BATCH_CMD'] + ' ' + main
['RANLIB']
555 if sys
.platform
== 'cygwin':
556 # cygwin has some header file issues...
557 main
.Append(CCFLAGS
=["-Wno-uninitialized"])
560 have_pkg_config
= readCommand(['pkg-config', '--version'], exception
='')
562 # Check for the protobuf compiler
564 main
['HAVE_PROTOC'] = True
565 protoc_version
= readCommand([main
['PROTOC'], '--version']).split()
567 # First two words should be "libprotoc x.y.z"
568 if len(protoc_version
) < 2 or protoc_version
[0] != 'libprotoc':
569 warning('Protocol buffer compiler (protoc) not found.\n'
570 'Please install protobuf-compiler for tracing support.')
571 main
['HAVE_PROTOC'] = False
573 # Based on the availability of the compress stream wrappers,
575 min_protoc_version
= '2.1.0'
576 if compareVersions(protoc_version
[1], min_protoc_version
) < 0:
577 warning('protoc version', min_protoc_version
,
578 'or newer required.\n'
579 'Installed version:', protoc_version
[1])
580 main
['HAVE_PROTOC'] = False
582 # Attempt to determine the appropriate include path and
583 # library path using pkg-config, that means we also need to
584 # check for pkg-config. Note that it is possible to use
585 # protobuf without the involvement of pkg-config. Later on we
586 # check go a library config check and at that point the test
587 # will fail if libprotobuf cannot be found.
590 # Attempt to establish what linking flags to add for
594 'pkg-config --cflags --libs-only-L protobuf')
596 warning('pkg-config could not get protobuf flags.')
597 except Exception as e
:
598 warning('While checking protoc version:', str(e
))
599 main
['HAVE_PROTOC'] = False
601 # Check for 'timeout' from GNU coreutils. If present, regressions will
602 # be run with a time limit. We require version 8.13 since we rely on
603 # support for the '--foreground' option.
604 if sys
.platform
.startswith('freebsd'):
605 timeout_lines
= readCommand(['gtimeout', '--version'],
606 exception
='').splitlines()
608 timeout_lines
= readCommand(['timeout', '--version'],
609 exception
='').splitlines()
610 # Get the first line and tokenize it
611 timeout_version
= timeout_lines
[0].split() if timeout_lines
else []
612 main
['TIMEOUT'] = timeout_version
and \
613 compareVersions(timeout_version
[-1], '8.13') >= 0
615 # Add a custom Check function to test for structure members.
616 def CheckMember(context
, include
, decl
, member
, include_quotes
="<>"):
617 context
.Message("Checking for member %s in %s..." %
623 (void)test.%(member)s;
626 """ % { "header" : include_quotes
[0] + include
+ include_quotes
[1],
631 ret
= context
.TryCompile(text
, extension
=".cc")
635 # Platform-specific configuration. Note again that we assume that all
636 # builds under a given build root run on the same host platform.
637 conf
= Configure(main
,
638 conf_dir
= joinpath(build_root
, '.scons_config'),
639 log_file
= joinpath(build_root
, 'scons_config.log'),
641 'CheckMember' : CheckMember
,
644 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
647 uname
= platform
.uname()
648 if uname
[0] == 'Darwin' and compareVersions(uname
[2], '9.0.0') >= 0:
649 if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
650 main
.Append(CCFLAGS
=['-arch', 'x86_64'])
651 main
.Append(CFLAGS
=['-arch', 'x86_64'])
652 main
.Append(LINKFLAGS
=['-arch', 'x86_64'])
653 main
.Append(ASFLAGS
=['-arch', 'x86_64'])
657 # Recent versions of scons substitute a "Null" object for Configure()
658 # when configuration isn't necessary, e.g., if the "--help" option is
659 # present. Unfortuantely this Null object always returns false,
660 # breaking all our configuration checks. We replace it with our own
661 # more optimistic null object that returns True instead.
663 def NullCheck(*args
, **kwargs
):
667 def __init__(self
, env
):
671 def __getattr__(self
, mname
):
674 conf
= NullConf(main
)
676 # Cache build files in the supplied directory.
677 if main
['M5_BUILD_CACHE']:
678 print('Using build cache located at', main
['M5_BUILD_CACHE'])
679 CacheDir(main
['M5_BUILD_CACHE'])
681 main
['USE_PYTHON'] = not GetOption('without_python')
682 if main
['USE_PYTHON']:
683 # Find Python include and library directories for embedding the
684 # interpreter. We rely on python-config to resolve the appropriate
685 # includes and linker flags. ParseConfig does not seem to understand
686 # the more exotic linker flags such as -Xlinker and -export-dynamic so
687 # we add them explicitly below. If you want to link in an alternate
688 # version of python, see above for instructions on how to invoke
689 # scons with the appropriate PATH set.
691 python_config
= find_first_prog(main
['PYTHON_CONFIG'])
692 if python_config
is None:
693 error("Can't find a suitable python-config, tried %s" % \
694 main
['PYTHON_CONFIG'])
696 print("Info: Using Python config: %s" % (python_config
, ))
697 py_includes
= readCommand([python_config
, '--includes'],
698 exception
='').split()
699 py_includes
= filter(lambda s
: match(r
'.*\/include\/.*',s
), py_includes
)
700 # Strip the -I from the include folders before adding them to the
702 py_includes
= map(lambda s
: s
[2:] if s
.startswith('-I') else s
, py_includes
)
703 main
.Append(CPPPATH
=py_includes
)
705 # Read the linker flags and split them into libraries and other link
706 # flags. The libraries are added later through the call the CheckLib.
707 py_ld_flags
= readCommand([python_config
, '--ldflags'],
708 exception
='').split()
710 for lib
in py_ld_flags
:
711 if not lib
.startswith('-l'):
712 main
.Append(LINKFLAGS
=[lib
])
715 if lib
not in py_libs
:
718 # verify that this stuff works
719 if not conf
.CheckHeader('Python.h', '<>'):
720 error("Check failed for Python.h header in", py_includes
, "\n"
721 "Two possible reasons:\n"
722 "1. Python headers are not installed (You can install the "
723 "package python-dev on Ubuntu and RedHat)\n"
724 "2. SCons is using a wrong C compiler. This can happen if "
725 "CC has the wrong value.\n"
726 "CC = %s" % main
['CC'])
729 if not conf
.CheckLib(lib
):
730 error("Can't find library %s required by python." % lib
)
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', 'alpha', all_isa_list
),
985 EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list
),
986 ListVariable('CPU_MODELS', 'CPU models',
987 sorted(n
for n
,m
in CpuModel
.dict.iteritems() if m
.default
),
988 sorted(CpuModel
.dict.keys())),
989 BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
991 BoolVariable('SS_COMPATIBLE_FP',
992 'Make floating-point results compatible with SimpleScalar',
994 BoolVariable('USE_SSE2',
995 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
997 BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock
),
998 BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv
),
999 BoolVariable('USE_PNG', 'Enable support for PNG images', have_png
),
1000 BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
1002 BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
1004 BoolVariable('USE_TUNTAP',
1005 'Enable using a tap device to bridge to the host network',
1007 BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1008 EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1010 EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1011 backtrace_impls
[-1], backtrace_impls
),
1012 ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
1014 BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5
),
1017 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1018 export_vars
+= ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1019 'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP',
1020 'PROTOCOL', 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1021 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1022 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1024 ###################################################
1026 # Define a SCons builder for configuration flag headers.
1028 ###################################################
1030 # This function generates a config header file that #defines the
1031 # variable symbol to the current variable setting (0 or 1). The source
1032 # operands are the name of the variable and a Value node containing the
1033 # value of the variable.
1034 def build_config_file(target
, source
, env
):
1035 (variable
, value
) = [s
.get_contents() for s
in source
]
1036 f
= file(str(target
[0]), 'w')
1037 print('#define', variable
, value
, file=f
)
1041 # Combine the two functions into a scons Action object.
1042 config_action
= MakeAction(build_config_file
, Transform("CONFIG H", 2))
1044 # The emitter munges the source & target node lists to reflect what
1045 # we're really doing.
1046 def config_emitter(target
, source
, env
):
1047 # extract variable name from Builder arg
1048 variable
= str(target
[0])
1049 # True target is config header file
1050 target
= joinpath('config', variable
.lower() + '.hh')
1052 if isinstance(val
, bool):
1053 # Force value to 0/1
1055 elif isinstance(val
, str):
1056 val
= '"' + val
+ '"'
1058 # Sources are variable name & value (packaged in SCons Value nodes)
1059 return ([target
], [Value(variable
), Value(val
)])
1061 config_builder
= Builder(emitter
= config_emitter
, action
= config_action
)
1063 main
.Append(BUILDERS
= { 'ConfigFile' : config_builder
})
1065 ###################################################
1067 # Builders for static and shared partially linked object files.
1069 ###################################################
1071 partial_static_builder
= Builder(action
=SCons
.Defaults
.LinkAction
,
1072 src_suffix
='$OBJSUFFIX',
1073 src_builder
=['StaticObject', 'Object'],
1074 LINKFLAGS
='$PLINKFLAGS',
1077 def partial_shared_emitter(target
, source
, env
):
1079 tgt
.attributes
.shared
= 1
1080 return (target
, source
)
1081 partial_shared_builder
= Builder(action
=SCons
.Defaults
.ShLinkAction
,
1082 emitter
=partial_shared_emitter
,
1083 src_suffix
='$SHOBJSUFFIX',
1084 src_builder
='SharedObject',
1085 SHLINKFLAGS
='$PSHLINKFLAGS',
1088 main
.Append(BUILDERS
= { 'PartialShared' : partial_shared_builder
,
1089 'PartialStatic' : partial_static_builder
})
1091 def add_local_rpath(env
, *targets
):
1092 '''Set up an RPATH for a library which lives in the build directory.
1094 The construction environment variable BIN_RPATH_PREFIX should be set to
1095 the relative path of the build directory starting from the location of the
1097 for target
in targets
:
1098 target
= env
.Entry(target
)
1099 if not isinstance(target
, SCons
.Node
.FS
.Dir
):
1101 relpath
= os
.path
.relpath(target
.abspath
, env
['BUILDDIR'])
1104 '${BIN_RPATH_PREFIX}',
1107 env
.Append(RPATH
=[env
.Literal(os
.path
.join(*components
))])
1109 if sys
.platform
!= "darwin":
1110 main
.Append(LINKFLAGS
=Split('-z origin'))
1112 main
.AddMethod(add_local_rpath
, 'AddLocalRPATH')
1114 # builds in ext are shared across all configs in the build root.
1115 ext_dir
= abspath(joinpath(str(main
.root
), 'ext'))
1117 for root
, dirs
, files
in os
.walk(ext_dir
):
1118 if 'SConscript' in files
:
1119 build_dir
= os
.path
.relpath(root
, ext_dir
)
1120 ext_build_dirs
.append(build_dir
)
1121 main
.SConscript(joinpath(root
, 'SConscript'),
1122 variant_dir
=joinpath(build_root
, build_dir
))
1124 gdb_xml_dir
= joinpath(ext_dir
, 'gdb-xml')
1125 Export('gdb_xml_dir')
1127 main
.Prepend(CPPPATH
=Dir('ext/pybind11/include/'))
1129 ###################################################
1131 # This builder and wrapper method are used to set up a directory with
1132 # switching headers. Those are headers which are in a generic location and
1133 # that include more specific headers from a directory chosen at build time
1134 # based on the current build settings.
1136 ###################################################
1138 def build_switching_header(target
, source
, env
):
1139 path
= str(target
[0])
1140 subdir
= str(source
[0])
1141 dp
, fp
= os
.path
.split(path
)
1142 dp
= os
.path
.relpath(os
.path
.realpath(dp
),
1143 os
.path
.realpath(env
['BUILDDIR']))
1144 with
open(path
, 'w') as hdr
:
1145 print('#include "%s/%s/%s"' % (dp
, subdir
, fp
), file=hdr
)
1147 switching_header_action
= MakeAction(build_switching_header
,
1148 Transform('GENERATE'))
1150 switching_header_builder
= Builder(action
=switching_header_action
,
1151 source_factory
=Value
,
1154 main
.Append(BUILDERS
= { 'SwitchingHeader': switching_header_builder
})
1156 def switching_headers(self
, headers
, source
):
1157 for header
in headers
:
1158 self
.SwitchingHeader(header
, source
)
1160 main
.AddMethod(switching_headers
, 'SwitchingHeaders')
1162 ###################################################
1164 # Define build environments for selected configurations.
1166 ###################################################
1168 for variant_path
in variant_paths
:
1169 if not GetOption('silent'):
1170 print("Building in", variant_path
)
1172 # Make a copy of the build-root environment to use for this config.
1174 env
['BUILDDIR'] = variant_path
1176 # variant_dir is the tail component of build path, and is used to
1177 # determine the build parameters (e.g., 'ALPHA_SE')
1178 (build_root
, variant_dir
) = splitpath(variant_path
)
1180 # Set env variables according to the build directory config.
1181 sticky_vars
.files
= []
1182 # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1183 # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1184 # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1185 current_vars_file
= joinpath(build_root
, 'variables', variant_dir
)
1186 if isfile(current_vars_file
):
1187 sticky_vars
.files
.append(current_vars_file
)
1188 if not GetOption('silent'):
1189 print("Using saved variables file %s" % current_vars_file
)
1190 elif variant_dir
in ext_build_dirs
:
1191 # Things in ext are built without a variant directory.
1194 # Build dir-specific variables file doesn't exist.
1196 # Make sure the directory is there so we can create it later
1197 opt_dir
= dirname(current_vars_file
)
1198 if not isdir(opt_dir
):
1201 # Get default build variables from source tree. Variables are
1202 # normally determined by name of $VARIANT_DIR, but can be
1203 # overridden by '--default=' arg on command line.
1204 default
= GetOption('default')
1205 opts_dir
= joinpath(main
.root
.abspath
, 'build_opts')
1207 default_vars_files
= [joinpath(build_root
, 'variables', default
),
1208 joinpath(opts_dir
, default
)]
1210 default_vars_files
= [joinpath(opts_dir
, variant_dir
)]
1211 existing_files
= filter(isfile
, default_vars_files
)
1213 default_vars_file
= existing_files
[0]
1214 sticky_vars
.files
.append(default_vars_file
)
1215 print("Variables file %s not found,\n using defaults in %s"
1216 % (current_vars_file
, default_vars_file
))
1218 error("Cannot find variables file %s or default file(s) %s"
1219 % (current_vars_file
, ' or '.join(default_vars_files
)))
1222 # Apply current variable settings to env
1223 sticky_vars
.Update(env
)
1225 help_texts
["local_vars"] += \
1226 "Build variables for %s:\n" % variant_dir \
1227 + sticky_vars
.GenerateHelpText(env
)
1229 # Process variable settings.
1231 if not have_fenv
and env
['USE_FENV']:
1232 warning("<fenv.h> not available; forcing USE_FENV to False in",
1234 env
['USE_FENV'] = False
1236 if not env
['USE_FENV']:
1237 warning("No IEEE FP rounding mode control in", variant_dir
+ ".\n"
1238 "FP results may deviate slightly from other platforms.")
1240 if not have_png
and env
['USE_PNG']:
1241 warning("<png.h> not available; forcing USE_PNG to False in",
1243 env
['USE_PNG'] = False
1246 env
.Append(LIBS
=['png'])
1249 env
.Append(LIBS
=['efence'])
1253 warning("Can not enable KVM, host seems to lack KVM support")
1254 env
['USE_KVM'] = False
1255 elif not is_isa_kvm_compatible(env
['TARGET_ISA']):
1256 print("Info: KVM support disabled due to unsupported host and "
1257 "target ISA combination")
1258 env
['USE_KVM'] = False
1260 if env
['USE_TUNTAP']:
1262 warning("Can't connect EtherTap with a tap device.")
1263 env
['USE_TUNTAP'] = False
1265 if env
['BUILD_GPU']:
1266 env
.Append(CPPDEFINES
=['BUILD_GPU'])
1268 # Warn about missing optional functionality
1270 if not main
['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1271 warning("perf_event headers lack support for the exclude_host "
1272 "attribute. KVM instruction counts will be inaccurate.")
1274 # Save sticky variable settings back to current variables file
1275 sticky_vars
.Save(current_vars_file
, env
)
1278 env
.Append(CCFLAGS
=['-msse2'])
1280 env
.Append(CCFLAGS
='$CCFLAGS_EXTRA')
1281 env
.Append(LINKFLAGS
='$LDFLAGS_EXTRA')
1283 # The src/SConscript file sets up the build rules in 'env' according
1284 # to the configured variables. It returns a list of environments,
1285 # one for each variant build (debug, opt, etc.)
1286 SConscript('src/SConscript', variant_dir
= variant_path
, exports
= 'env')
1290 Usage: scons [scons options] [build variables] [target(s)]
1292 Extra scons options:
1295 Global build variables: