3 # Copyright (c) 2013, 2015-2017 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
101 from m5
.util
import compareVersions
, readCommand
112 # There's a bug in scons in that (1) by default, the help texts from
113 # AddOption() are supposed to be displayed when you type 'scons -h'
114 # and (2) you can override the help displayed by 'scons -h' using the
115 # Help() function, but these two features are incompatible: once
116 # you've overridden the help text using Help(), there's no way to get
117 # at the help texts from AddOptions. See:
118 # http://scons.tigris.org/issues/show_bug.cgi?id=2356
119 # http://scons.tigris.org/issues/show_bug.cgi?id=2611
120 # This hack lets us extract the help text from AddOptions and
121 # re-inject it via Help(). Ideally someday this bug will be fixed and
122 # we can just use AddOption directly.
123 def AddLocalOption(*args
, **kwargs
):
126 help = " " + ", ".join(args
)
129 if length
>= col_width
:
130 help += "\n" + " " * col_width
132 help += " " * (col_width
- length
)
133 help += kwargs
["help"]
134 help_texts
["options"] += help + "\n"
136 AddOption(*args
, **kwargs
)
138 AddLocalOption('--colors', dest
='use_colors', action
='store_true',
139 help="Add color to abbreviated scons output")
140 AddLocalOption('--no-colors', dest
='use_colors', action
='store_false',
141 help="Don't add color to abbreviated scons output")
142 AddLocalOption('--with-cxx-config', dest
='with_cxx_config',
144 help="Build with support for C++-based configuration")
145 AddLocalOption('--default', dest
='default', type='string', action
='store',
146 help='Override which build_opts file to use for defaults')
147 AddLocalOption('--ignore-style', dest
='ignore_style', action
='store_true',
148 help='Disable style checking hooks')
149 AddLocalOption('--gold-linker', dest
='gold_linker', action
='store_true',
150 help='Use the gold linker')
151 AddLocalOption('--no-lto', dest
='no_lto', action
='store_true',
152 help='Disable Link-Time Optimization for fast')
153 AddLocalOption('--force-lto', dest
='force_lto', action
='store_true',
154 help='Use Link-Time Optimization instead of partial linking' +
155 ' when the compiler doesn\'t support using them together.')
156 AddLocalOption('--update-ref', dest
='update_ref', action
='store_true',
157 help='Update test reference outputs')
158 AddLocalOption('--verbose', dest
='verbose', action
='store_true',
159 help='Print full tool command lines')
160 AddLocalOption('--without-python', dest
='without_python',
162 help='Build without Python configuration support')
163 AddLocalOption('--without-tcmalloc', dest
='without_tcmalloc',
165 help='Disable linking against tcmalloc')
166 AddLocalOption('--with-ubsan', dest
='with_ubsan', action
='store_true',
167 help='Build with Undefined Behavior Sanitizer if available')
168 AddLocalOption('--with-asan', dest
='with_asan', action
='store_true',
169 help='Build with Address Sanitizer if available')
171 if GetOption('no_lto') and GetOption('force_lto'):
172 print('--no-lto and --force-lto are mutually exclusive')
175 ########################################################################
177 # Set up the main build environment.
179 ########################################################################
183 from gem5_scons
import Transform
184 from gem5_scons
.util
import get_termcap
185 termcap
= get_termcap()
187 main_dict_keys
= main
.Dictionary().keys()
189 # Check that we have a C/C++ compiler
190 if not ('CC' in main_dict_keys
and 'CXX' in main_dict_keys
):
191 print("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 print("Error: no non-leaf 'build' dir found on target path", t
)
253 this_build_root
= joinpath('/',*path_dirs
[:build_top
+1])
255 build_root
= this_build_root
257 if this_build_root
!= build_root
:
258 print("Error: build targets not under same build root\n"
259 " %s\n %s" % (build_root
, this_build_root
))
261 variant_path
= joinpath('/',*path_dirs
[:build_top
+2])
262 if variant_path
not in variant_paths
:
263 variant_paths
.append(variant_path
)
265 # Make sure build_root exists (might not if this is the first build there)
266 if not isdir(build_root
):
268 main
['BUILDROOT'] = build_root
272 main
.SConsignFile(joinpath(build_root
, "sconsign"))
274 # Default duplicate option is to use hard links, but this messes up
275 # when you use emacs to edit a file in the target dir, as emacs moves
276 # file to file~ then copies to file, breaking the link. Symbolic
277 # (soft) links work better.
278 main
.SetOption('duplicate', 'soft-copy')
281 # Set up global sticky variables... these are common to an entire build
282 # tree (not specific to a particular build like ALPHA_SE)
285 global_vars_file
= joinpath(build_root
, 'variables.global')
287 global_vars
= Variables(global_vars_file
, args
=ARGUMENTS
)
289 global_vars
.AddVariables(
290 ('CC', 'C compiler', environ
.get('CC', main
['CC'])),
291 ('CXX', 'C++ compiler', environ
.get('CXX', main
['CXX'])),
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 print('Error: How can we have two at the same time?')
361 # Set up default C++ compiler flags
362 if main
['GCC'] or main
['CLANG']:
363 # As gcc and clang share many flags, do the common parts here
364 main
.Append(CCFLAGS
=['-pipe'])
365 main
.Append(CCFLAGS
=['-fno-strict-aliasing'])
366 # Enable -Wall and -Wextra and then disable the few warnings that
367 # we consistently violate
368 main
.Append(CCFLAGS
=['-Wall', '-Wundef', '-Wextra',
369 '-Wno-sign-compare', '-Wno-unused-parameter'])
370 # We always compile using C++11
371 main
.Append(CXXFLAGS
=['-std=c++11'])
372 if sys
.platform
.startswith('freebsd'):
373 main
.Append(CCFLAGS
=['-I/usr/local/include'])
374 main
.Append(CXXFLAGS
=['-I/usr/local/include'])
376 main
['FILTER_PSHLINKFLAGS'] = lambda x
: str(x
).replace(' -shared', '')
377 main
['PSHLINKFLAGS'] = main
.subst('${FILTER_PSHLINKFLAGS(SHLINKFLAGS)}')
378 if GetOption('gold_linker'):
379 main
.Append(LINKFLAGS
='-fuse-ld=gold')
380 main
['PLINKFLAGS'] = main
.subst('${LINKFLAGS}')
381 shared_partial_flags
= ['-r', '-nostdlib']
382 main
.Append(PSHLINKFLAGS
=shared_partial_flags
)
383 main
.Append(PLINKFLAGS
=shared_partial_flags
)
385 # Treat warnings as errors but white list some warnings that we
386 # want to allow (e.g., deprecation warnings).
387 main
.Append(CCFLAGS
=['-Werror',
388 '-Wno-error=deprecated-declarations',
389 '-Wno-error=deprecated',
392 print(termcap
.Yellow
+ termcap
.Bold
+ 'Error' + termcap
.Normal
, end
=' ')
393 print("Don't know what compiler options to use for your compiler.")
394 print(termcap
.Yellow
+ ' compiler:' + termcap
.Normal
, main
['CXX'])
395 print(termcap
.Yellow
+ ' version:' + termcap
.Normal
, end
= ' ')
397 print(termcap
.Yellow
+ termcap
.Bold
+ "COMMAND NOT FOUND!" +
400 print(CXX_version
.replace('\n', '<nl>'))
401 print(" If you're trying to use a compiler other than GCC")
402 print(" or clang, there appears to be something wrong with your")
403 print(" environment.")
405 print(" If you are trying to use a compiler other than those listed")
406 print(" above you will need to ease fix SConstruct and ")
407 print(" src/SConscript to support that compiler.")
411 # Check for a supported version of gcc. >= 4.8 is chosen for its
412 # level of c++11 support. See
413 # http://gcc.gnu.org/projects/cxx0x.html for details.
414 gcc_version
= readCommand([main
['CXX'], '-dumpversion'], exception
=False)
415 if compareVersions(gcc_version
, "4.8") < 0:
416 print('Error: gcc version 4.8 or newer required.')
417 print(' Installed version: ', gcc_version
)
420 main
['GCC_VERSION'] = gcc_version
422 if compareVersions(gcc_version
, '4.9') >= 0:
423 # Incremental linking with LTO is currently broken in gcc versions
424 # 4.9 and above. A version where everything works completely hasn't
425 # yet been identified.
427 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
428 main
['BROKEN_INCREMENTAL_LTO'] = True
429 if compareVersions(gcc_version
, '6.0') >= 0:
430 # gcc versions 6.0 and greater accept an -flinker-output flag which
431 # selects what type of output the linker should generate. This is
432 # necessary for incremental lto to work, but is also broken in
433 # current versions of gcc. It may not be necessary in future
434 # versions. We add it here since it might be, and as a reminder that
435 # it exists. It's excluded if lto is being forced.
437 # https://gcc.gnu.org/gcc-6/changes.html
438 # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
439 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
440 if not GetOption('force_lto'):
441 main
.Append(PSHLINKFLAGS
='-flinker-output=rel')
442 main
.Append(PLINKFLAGS
='-flinker-output=rel')
444 # Make sure we warn if the user has requested to compile with the
445 # Undefined Benahvior Sanitizer and this version of gcc does not
447 if GetOption('with_ubsan') and \
448 compareVersions(gcc_version
, '4.9') < 0:
449 print(termcap
.Yellow
+ termcap
.Bold
+
450 'Warning: UBSan is only supported using gcc 4.9 and later.' +
453 disable_lto
= GetOption('no_lto')
454 if not disable_lto
and main
.get('BROKEN_INCREMENTAL_LTO', False) and \
455 not GetOption('force_lto'):
456 print(termcap
.Yellow
+ termcap
.Bold
+
457 'Warning: Your compiler doesn\'t support incremental linking' +
458 ' and lto at the same time, so lto is being disabled. To force' +
459 ' lto on anyway, use the --force-lto option. That will disable' +
460 ' partial linking.' +
464 # Add the appropriate Link-Time Optimization (LTO) flags
465 # unless LTO is explicitly turned off. Note that these flags
466 # are only used by the fast target.
468 # Pass the LTO flag when compiling to produce GIMPLE
469 # output, we merely create the flags here and only append
471 main
['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
473 # Use the same amount of jobs for LTO as we are running
475 main
['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
477 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin-malloc', '-fno-builtin-calloc',
478 '-fno-builtin-realloc', '-fno-builtin-free'])
480 # The address sanitizer is available for gcc >= 4.8
481 if GetOption('with_asan'):
482 if GetOption('with_ubsan') and \
483 compareVersions(main
['GCC_VERSION'], '4.9') >= 0:
484 main
.Append(CCFLAGS
=['-fsanitize=address,undefined',
485 '-fno-omit-frame-pointer'],
486 LINKFLAGS
='-fsanitize=address,undefined')
488 main
.Append(CCFLAGS
=['-fsanitize=address',
489 '-fno-omit-frame-pointer'],
490 LINKFLAGS
='-fsanitize=address')
491 # Only gcc >= 4.9 supports UBSan, so check both the version
492 # and the command-line option before adding the compiler and
494 elif GetOption('with_ubsan') and \
495 compareVersions(main
['GCC_VERSION'], '4.9') >= 0:
496 main
.Append(CCFLAGS
='-fsanitize=undefined')
497 main
.Append(LINKFLAGS
='-fsanitize=undefined')
500 # Check for a supported version of clang, >= 3.1 is needed to
501 # support similar features as gcc 4.8. See
502 # http://clang.llvm.org/cxx_status.html for details
503 clang_version_re
= re
.compile(".* version (\d+\.\d+)")
504 clang_version_match
= clang_version_re
.search(CXX_version
)
505 if (clang_version_match
):
506 clang_version
= clang_version_match
.groups()[0]
507 if compareVersions(clang_version
, "3.1") < 0:
508 print('Error: clang version 3.1 or newer required.')
509 print(' Installed version:', clang_version
)
512 print('Error: Unable to determine clang version.')
515 # clang has a few additional warnings that we disable, extraneous
516 # parantheses are allowed due to Ruby's printing of the AST,
517 # finally self assignments are allowed as the generated CPU code
519 main
.Append(CCFLAGS
=['-Wno-parentheses',
521 # Some versions of libstdc++ (4.8?) seem to
522 # use struct hash and class hash
524 '-Wno-mismatched-tags',
527 main
.Append(TCMALLOC_CCFLAGS
=['-fno-builtin'])
529 # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
530 # opposed to libstdc++, as the later is dated.
531 if sys
.platform
== "darwin":
532 main
.Append(CXXFLAGS
=['-stdlib=libc++'])
533 main
.Append(LIBS
=['c++'])
535 # On FreeBSD we need libthr.
536 if sys
.platform
.startswith('freebsd'):
537 main
.Append(LIBS
=['thr'])
539 # We require clang >= 3.1, so there is no need to check any
541 if GetOption('with_ubsan'):
542 if GetOption('with_asan'):
543 main
.Append(CCFLAGS
=['-fsanitize=address,undefined',
544 '-fno-omit-frame-pointer'],
545 LINKFLAGS
='-fsanitize=address,undefined')
547 main
.Append(CCFLAGS
='-fsanitize=undefined',
548 LINKFLAGS
='-fsanitize=undefined')
550 elif GetOption('with_asan'):
551 main
.Append(CCFLAGS
=['-fsanitize=address',
552 '-fno-omit-frame-pointer'],
553 LINKFLAGS
='-fsanitize=address')
556 print(termcap
.Yellow
+ termcap
.Bold
+ 'Error' + termcap
.Normal
, end
=' ')
557 print("Don't know what compiler options to use for your compiler.")
558 print(termcap
.Yellow
+ ' compiler:' + termcap
.Normal
, main
['CXX'])
559 print(termcap
.Yellow
+ ' version:' + termcap
.Normal
, end
=' ')
561 print(termcap
.Yellow
+ termcap
.Bold
+ "COMMAND NOT FOUND!" +
564 print(CXX_version
.replace('\n', '<nl>'))
565 print(" If you're trying to use a compiler other than GCC")
566 print(" or clang, there appears to be something wrong with your")
567 print(" environment.")
569 print(" If you are trying to use a compiler other than those listed")
570 print(" above you will need to ease fix SConstruct and ")
571 print(" src/SConscript to support that compiler.")
574 # Set up common yacc/bison flags (needed for Ruby)
575 main
['YACCFLAGS'] = '-d'
576 main
['YACCHXXFILESUFFIX'] = '.hh'
578 # Do this after we save setting back, or else we'll tack on an
579 # extra 'qdo' every time we run scons.
581 main
['CC'] = main
['BATCH_CMD'] + ' ' + main
['CC']
582 main
['CXX'] = main
['BATCH_CMD'] + ' ' + main
['CXX']
583 main
['AS'] = main
['BATCH_CMD'] + ' ' + main
['AS']
584 main
['AR'] = main
['BATCH_CMD'] + ' ' + main
['AR']
585 main
['RANLIB'] = main
['BATCH_CMD'] + ' ' + main
['RANLIB']
587 if sys
.platform
== 'cygwin':
588 # cygwin has some header file issues...
589 main
.Append(CCFLAGS
=["-Wno-uninitialized"])
591 # Check for the protobuf compiler
592 protoc_version
= readCommand([main
['PROTOC'], '--version'],
593 exception
='').split()
595 # First two words should be "libprotoc x.y.z"
596 if len(protoc_version
) < 2 or protoc_version
[0] != 'libprotoc':
597 print(termcap
.Yellow
+ termcap
.Bold
+
598 'Warning: Protocol buffer compiler (protoc) not found.\n' +
599 ' Please install protobuf-compiler for tracing support.' +
601 main
['PROTOC'] = False
603 # Based on the availability of the compress stream wrappers,
605 min_protoc_version
= '2.1.0'
606 if compareVersions(protoc_version
[1], min_protoc_version
) < 0:
607 print(termcap
.Yellow
+ termcap
.Bold
+
608 'Warning: protoc version', min_protoc_version
,
609 'or newer required.\n' +
610 ' Installed version:', protoc_version
[1],
612 main
['PROTOC'] = False
614 # Attempt to determine the appropriate include path and
615 # library path using pkg-config, that means we also need to
616 # check for pkg-config. Note that it is possible to use
617 # protobuf without the involvement of pkg-config. Later on we
618 # check go a library config check and at that point the test
619 # will fail if libprotobuf cannot be found.
620 if readCommand(['pkg-config', '--version'], exception
=''):
622 # Attempt to establish what linking flags to add for protobuf
624 main
.ParseConfig('pkg-config --cflags --libs-only-L protobuf')
626 print(termcap
.Yellow
+ termcap
.Bold
+
627 'Warning: pkg-config could not get protobuf flags.' +
631 # Check for 'timeout' from GNU coreutils. If present, regressions will
632 # be run with a time limit. We require version 8.13 since we rely on
633 # support for the '--foreground' option.
634 if sys
.platform
.startswith('freebsd'):
635 timeout_lines
= readCommand(['gtimeout', '--version'],
636 exception
='').splitlines()
638 timeout_lines
= readCommand(['timeout', '--version'],
639 exception
='').splitlines()
640 # Get the first line and tokenize it
641 timeout_version
= timeout_lines
[0].split() if timeout_lines
else []
642 main
['TIMEOUT'] = timeout_version
and \
643 compareVersions(timeout_version
[-1], '8.13') >= 0
645 # Add a custom Check function to test for structure members.
646 def CheckMember(context
, include
, decl
, member
, include_quotes
="<>"):
647 context
.Message("Checking for member %s in %s..." %
653 (void)test.%(member)s;
656 """ % { "header" : include_quotes
[0] + include
+ include_quotes
[1],
661 ret
= context
.TryCompile(text
, extension
=".cc")
665 # Platform-specific configuration. Note again that we assume that all
666 # builds under a given build root run on the same host platform.
667 conf
= Configure(main
,
668 conf_dir
= joinpath(build_root
, '.scons_config'),
669 log_file
= joinpath(build_root
, 'scons_config.log'),
671 'CheckMember' : CheckMember
,
674 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
677 uname
= platform
.uname()
678 if uname
[0] == 'Darwin' and compareVersions(uname
[2], '9.0.0') >= 0:
679 if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
680 main
.Append(CCFLAGS
=['-arch', 'x86_64'])
681 main
.Append(CFLAGS
=['-arch', 'x86_64'])
682 main
.Append(LINKFLAGS
=['-arch', 'x86_64'])
683 main
.Append(ASFLAGS
=['-arch', 'x86_64'])
687 # Recent versions of scons substitute a "Null" object for Configure()
688 # when configuration isn't necessary, e.g., if the "--help" option is
689 # present. Unfortuantely this Null object always returns false,
690 # breaking all our configuration checks. We replace it with our own
691 # more optimistic null object that returns True instead.
693 def NullCheck(*args
, **kwargs
):
697 def __init__(self
, env
):
701 def __getattr__(self
, mname
):
704 conf
= NullConf(main
)
706 # Cache build files in the supplied directory.
707 if main
['M5_BUILD_CACHE']:
708 print('Using build cache located at', main
['M5_BUILD_CACHE'])
709 CacheDir(main
['M5_BUILD_CACHE'])
711 main
['USE_PYTHON'] = not GetOption('without_python')
712 if main
['USE_PYTHON']:
713 # Find Python include and library directories for embedding the
714 # interpreter. We rely on python-config to resolve the appropriate
715 # includes and linker flags. ParseConfig does not seem to understand
716 # the more exotic linker flags such as -Xlinker and -export-dynamic so
717 # we add them explicitly below. If you want to link in an alternate
718 # version of python, see above for instructions on how to invoke
719 # scons with the appropriate PATH set.
721 python_config
= find_first_prog(main
['PYTHON_CONFIG'])
722 if python_config
is None:
723 print("Error: can't find a suitable python-config, tried %s" % \
724 main
['PYTHON_CONFIG'])
727 print("Info: Using Python config: %s" % (python_config
, ))
728 py_includes
= readCommand([python_config
, '--includes'],
729 exception
='').split()
730 py_includes
= filter(lambda s
: match(r
'.*\/include\/.*',s
), py_includes
)
731 # Strip the -I from the include folders before adding them to the
733 py_includes
= map(lambda s
: s
[2:] if s
.startswith('-I') else s
, py_includes
)
734 main
.Append(CPPPATH
=py_includes
)
736 # Read the linker flags and split them into libraries and other link
737 # flags. The libraries are added later through the call the CheckLib.
738 py_ld_flags
= readCommand([python_config
, '--ldflags'],
739 exception
='').split()
741 for lib
in py_ld_flags
:
742 if not lib
.startswith('-l'):
743 main
.Append(LINKFLAGS
=[lib
])
746 if lib
not in py_libs
:
749 # verify that this stuff works
750 if not conf
.CheckHeader('Python.h', '<>'):
751 print("Error: Check failed for Python.h header in", py_includes
)
752 print("Two possible reasons:")
753 print("1. Python headers are not installed (You can install the "
754 "package python-dev on Ubuntu and RedHat)")
755 print("2. SCons is using a wrong C compiler. This can happen if "
756 "CC has the wrong value.")
757 print("CC = %s" % main
['CC'])
761 if not conf
.CheckLib(lib
):
762 print("Error: can't find library %s required by python" % lib
)
765 # On Solaris you need to use libsocket for socket ops
766 if not conf
.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
767 if not conf
.CheckLibWithHeader('socket', 'sys/socket.h', 'C++', 'accept(0,0,0);'):
768 print("Can't find library with socket calls (e.g. accept())")
771 # Check for zlib. If the check passes, libz will be automatically
772 # added to the LIBS environment variable.
773 if not conf
.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
774 print('Error: did not find needed zlib compression library '
775 'and/or zlib.h header file.')
776 print(' Please install zlib and try again.')
779 # If we have the protobuf compiler, also make sure we have the
780 # development libraries. If the check passes, libprotobuf will be
781 # automatically added to the LIBS environment variable. After
782 # this, we can use the HAVE_PROTOBUF flag to determine if we have
783 # got both protoc and libprotobuf available.
784 main
['HAVE_PROTOBUF'] = main
['PROTOC'] and \
785 conf
.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
786 'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
788 # Valgrind gets much less confused if you tell it when you're using
789 # alternative stacks.
790 main
['HAVE_VALGRIND'] = conf
.CheckCHeader('valgrind/valgrind.h')
792 # If we have the compiler but not the library, print another warning.
793 if main
['PROTOC'] and not main
['HAVE_PROTOBUF']:
794 print(termcap
.Yellow
+ termcap
.Bold
+
795 'Warning: did not find protocol buffer library and/or headers.\n' +
796 ' Please install libprotobuf-dev for tracing support.' +
801 conf
.CheckLibWithHeader(None, 'time.h', 'C',
802 'clock_nanosleep(0,0,NULL,NULL);') or \
803 conf
.CheckLibWithHeader('rt', 'time.h', 'C',
804 'clock_nanosleep(0,0,NULL,NULL);')
806 have_posix_timers
= \
807 conf
.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
808 'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
810 if not GetOption('without_tcmalloc'):
811 if conf
.CheckLib('tcmalloc'):
812 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
813 elif conf
.CheckLib('tcmalloc_minimal'):
814 main
.Append(CCFLAGS
=main
['TCMALLOC_CCFLAGS'])
816 print(termcap
.Yellow
+ termcap
.Bold
+
817 "You can get a 12% performance improvement by "
818 "installing tcmalloc (libgoogle-perftools-dev package "
819 "on Ubuntu or RedHat)." + termcap
.Normal
)
822 # Detect back trace implementations. The last implementation in the
823 # list will be used by default.
824 backtrace_impls
= [ "none" ]
826 backtrace_checker
= 'char temp;' + \
827 ' backtrace_symbols_fd((void*)&temp, 0, 0);'
828 if conf
.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker
):
829 backtrace_impls
.append("glibc")
830 elif conf
.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
832 # NetBSD and FreeBSD need libexecinfo.
833 backtrace_impls
.append("glibc")
834 main
.Append(LIBS
=['execinfo'])
836 if backtrace_impls
[-1] == "none":
837 default_backtrace_impl
= "none"
838 print(termcap
.Yellow
+ termcap
.Bold
+
839 "No suitable back trace implementation found." +
842 if not have_posix_clock
:
843 print("Can't find library for POSIX clocks.")
845 # Check for <fenv.h> (C99 FP environment control)
846 have_fenv
= conf
.CheckHeader('fenv.h', '<>')
848 print("Warning: Header file <fenv.h> not found.")
849 print(" This host has no IEEE FP rounding mode control.")
851 # Check for <png.h> (libpng library needed if wanting to dump
852 # frame buffer image in png format)
853 have_png
= conf
.CheckHeader('png.h', '<>')
855 print("Warning: Header file <png.h> not found.")
856 print(" This host has no libpng library.")
857 print(" Disabling support for PNG framebuffers.")
859 # Check if we should enable KVM-based hardware virtualization. The API
860 # we rely on exists since version 2.6.36 of the kernel, but somehow
861 # the KVM_API_VERSION does not reflect the change. We test for one of
862 # the types as a fall back.
863 have_kvm
= conf
.CheckHeader('linux/kvm.h', '<>')
865 print("Info: Compatible header file <linux/kvm.h> not found, "
866 "disabling KVM support.")
868 # Check if the TUN/TAP driver is available.
869 have_tuntap
= conf
.CheckHeader('linux/if_tun.h', '<>')
871 print("Info: Compatible header file <linux/if_tun.h> not found.")
873 # x86 needs support for xsave. We test for the structure here since we
874 # won't be able to run new tests by the time we know which ISA we're
876 have_kvm_xsave
= conf
.CheckTypeSize('struct kvm_xsave',
877 '#include <linux/kvm.h>') != 0
879 # Check if the requested target ISA is compatible with the host
880 def is_isa_kvm_compatible(isa
):
883 host_isa
= platform
.machine()
885 print("Warning: Failed to determine host ISA.")
888 if not have_posix_timers
:
889 print("Warning: Can not enable KVM, host seems to lack support "
894 return host_isa
in ( "armv7l", "aarch64" )
896 if host_isa
!= "x86_64":
899 if not have_kvm_xsave
:
900 print("KVM on x86 requires xsave support in kernel headers.")
908 # Check if the exclude_host attribute is available. We want this to
909 # get accurate instruction counts in KVM.
910 main
['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf
.CheckMember(
911 'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
914 ######################################################################
916 # Finish the configuration
920 ######################################################################
922 # Collect all non-global variables
925 # Define the universe of supported ISAs
927 all_gpu_isa_list
= [ ]
928 Export('all_isa_list')
929 Export('all_gpu_isa_list')
931 class CpuModel(object):
932 '''The CpuModel class encapsulates everything the ISA parser needs to
933 know about a particular CPU model.'''
935 # Dict of available CPU model objects. Accessible as CpuModel.dict.
938 # Constructor. Automatically adds models to CpuModel.dict.
939 def __init__(self
, name
, default
=False):
940 self
.name
= name
# name of model
942 # This cpu is enabled by default
943 self
.default
= default
946 if name
in CpuModel
.dict:
947 raise AttributeError, "CpuModel '%s' already registered" % name
948 CpuModel
.dict[name
] = self
952 # Sticky variables get saved in the variables file so they persist from
953 # one invocation to the next (unless overridden, in which case the new
954 # value becomes sticky).
955 sticky_vars
= Variables(args
=ARGUMENTS
)
956 Export('sticky_vars')
958 # Sticky variables that should be exported
960 Export('export_vars')
964 Export('all_protocols')
966 Export('protocol_dirs')
968 Export('slicc_includes')
970 # Walk the tree and execute all SConsopts scripts that wil add to the
972 if GetOption('verbose'):
973 print("Reading SConsopts")
974 for bdir
in [ base_dir
] + extras_dir_list
:
976 print("Error: directory '%s' does not exist" % bdir
)
978 for root
, dirs
, files
in os
.walk(bdir
):
979 if 'SConsopts' in files
:
980 if GetOption('verbose'):
981 print("Reading", joinpath(root
, 'SConsopts'))
982 SConscript(joinpath(root
, 'SConsopts'))
985 all_gpu_isa_list
.sort()
987 sticky_vars
.AddVariables(
988 EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list
),
989 EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list
),
990 ListVariable('CPU_MODELS', 'CPU models',
991 sorted(n
for n
,m
in CpuModel
.dict.iteritems() if m
.default
),
992 sorted(CpuModel
.dict.keys())),
993 BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
995 BoolVariable('SS_COMPATIBLE_FP',
996 'Make floating-point results compatible with SimpleScalar',
998 BoolVariable('USE_SSE2',
999 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
1001 BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock
),
1002 BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv
),
1003 BoolVariable('USE_PNG', 'Enable support for PNG images', have_png
),
1004 BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
1006 BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
1008 BoolVariable('USE_TUNTAP',
1009 'Enable using a tap device to bridge to the host network',
1011 BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
1012 EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
1014 EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
1015 backtrace_impls
[-1], backtrace_impls
)
1018 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1019 export_vars
+= ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1020 'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP',
1021 'PROTOCOL', 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1022 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG']
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 target
.isdir():
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 print("Error: cannot find variables file %s or "
1219 "default file(s) %s"
1220 % (current_vars_file
, ' or '.join(default_vars_files
)))
1223 # Apply current variable settings to env
1224 sticky_vars
.Update(env
)
1226 help_texts
["local_vars"] += \
1227 "Build variables for %s:\n" % variant_dir \
1228 + sticky_vars
.GenerateHelpText(env
)
1230 # Process variable settings.
1232 if not have_fenv
and env
['USE_FENV']:
1233 print("Warning: <fenv.h> not available; "
1234 "forcing USE_FENV to False in", variant_dir
+ ".")
1235 env
['USE_FENV'] = False
1237 if not env
['USE_FENV']:
1238 print("Warning: No IEEE FP rounding mode control in",
1240 print(" FP results may deviate slightly from other platforms.")
1242 if not have_png
and env
['USE_PNG']:
1243 print("Warning: <png.h> not available; "
1244 "forcing USE_PNG to False in", variant_dir
+ ".")
1245 env
['USE_PNG'] = False
1248 env
.Append(LIBS
=['png'])
1251 env
.Append(LIBS
=['efence'])
1255 print("Warning: Can not enable KVM, host seems to "
1257 env
['USE_KVM'] = False
1258 elif not is_isa_kvm_compatible(env
['TARGET_ISA']):
1259 print("Info: KVM support disabled due to unsupported host and "
1260 "target ISA combination")
1261 env
['USE_KVM'] = False
1263 if env
['USE_TUNTAP']:
1265 print("Warning: Can't connect EtherTap with a tap device.")
1266 env
['USE_TUNTAP'] = False
1268 if env
['BUILD_GPU']:
1269 env
.Append(CPPDEFINES
=['BUILD_GPU'])
1271 # Warn about missing optional functionality
1273 if not main
['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1274 print("Warning: perf_event headers lack support for the "
1275 "exclude_host attribute. KVM instruction counts will "
1278 # Save sticky variable settings back to current variables file
1279 sticky_vars
.Save(current_vars_file
, env
)
1282 env
.Append(CCFLAGS
=['-msse2'])
1284 # The src/SConscript file sets up the build rules in 'env' according
1285 # to the configured variables. It returns a list of environments,
1286 # one for each variant build (debug, opt, etc.)
1287 SConscript('src/SConscript', variant_dir
= variant_path
, exports
= 'env')
1291 Usage: scons [scons options] [build variables] [target(s)]
1293 Extra scons options:
1296 Global build variables: