scons: Fix an error about an unrecognized compiler.
[gem5.git] / SConstruct
1 # -*- mode:python -*-
2
3 # Copyright (c) 2013, 2015-2020 ARM Limited
4 # All rights reserved.
5 #
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.
14 #
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.
19 #
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.
30 #
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.
42 #
43 # Authors: Steve Reinhardt
44 # Nathan Binkert
45
46 ###################################################
47 #
48 # SCons top-level build description (SConstruct) file.
49 #
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).
54 #
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.
59 #
60 # Examples:
61 #
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
66 #
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
70 # file.
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
73 #
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
77 # options as well.
78 #
79 ###################################################
80
81 from __future__ import print_function
82
83 # Global Python includes
84 import itertools
85 import os
86 import re
87 import shutil
88 import subprocess
89 import sys
90
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
95 from re import match
96
97 # SCons includes
98 import SCons
99 import SCons.Node
100 import SCons.Node.FS
101
102 from m5.util import compareVersions, readCommand
103
104 help_texts = {
105 "options" : "",
106 "global_vars" : "",
107 "local_vars" : ""
108 }
109
110 Export("help_texts")
111
112
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):
125 col_width = 30
126
127 help = " " + ", ".join(args)
128 if "help" in kwargs:
129 length = len(help)
130 if length >= col_width:
131 help += "\n" + " " * col_width
132 else:
133 help += " " * (col_width - length)
134 help += kwargs["help"]
135 help_texts["options"] += help + "\n"
136
137 AddOption(*args, **kwargs)
138
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',
144 action='store_true',
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',
162 action='store_true',
163 help='Build without Python configuration support')
164 AddLocalOption('--without-tcmalloc', dest='without_tcmalloc',
165 action='store_true',
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')
171
172 from gem5_scons import Transform, error, warning
173
174 if GetOption('no_lto') and GetOption('force_lto'):
175 error('--no-lto and --force-lto are mutually exclusive')
176
177 ########################################################################
178 #
179 # Set up the main build environment.
180 #
181 ########################################################################
182
183 main = Environment()
184
185 from gem5_scons.util import get_termcap
186 termcap = get_termcap()
187
188 main_dict_keys = main.Dictionary().keys()
189
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)")
193
194 ###################################################
195 #
196 # Figure out which configurations to set up based on the path(s) of
197 # the target(s).
198 #
199 ###################################################
200
201 # Find default configuration & binary.
202 Default(environ.get('M5_DEFAULT_BINARY', 'build/ALPHA/gem5.debug'))
203
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):
207 if l[i] == elt:
208 return i
209 raise ValueError("element not found")
210
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))))
216 for p in path_list]
217
218 def find_first_prog(prog_names):
219 """Find the absolute path to the first existing binary in prog_names"""
220
221 if not isinstance(prog_names, (list, tuple)):
222 prog_names = [ prog_names ]
223
224 for p in prog_names:
225 p = main.WhereIs(p)
226 if p is not None:
227 return p
228
229 return None
230
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.
236
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)
241
242 # Generate a list of the unique build roots and configs that the
243 # collected targets reference.
244 variant_paths = []
245 build_root = None
246 for t in BUILD_TARGETS:
247 path_dirs = t.split('/')
248 try:
249 build_top = rfind(path_dirs, 'build', -2)
250 except:
251 error("No non-leaf 'build' dir found on target path.", t)
252 this_build_root = joinpath('/',*path_dirs[:build_top+1])
253 if not build_root:
254 build_root = this_build_root
255 else:
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)
262
263 # Make sure build_root exists (might not if this is the first build there)
264 if not isdir(build_root):
265 mkdir(build_root)
266 main['BUILDROOT'] = build_root
267
268 Export('main')
269
270 main.SConsignFile(joinpath(build_root, "sconsign"))
271
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')
277
278 #
279 # Set up global sticky variables... these are common to an entire build
280 # tree (not specific to a particular build like ALPHA_SE)
281 #
282
283 global_vars_file = joinpath(build_root, 'variables.global')
284
285 global_vars = Variables(global_vars_file, args=ARGUMENTS)
286
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', '')
299 )
300
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)
304
305 # Save sticky variable settings back to current variables file
306 global_vars.Save(global_vars_file, main)
307
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
311 if main['EXTRAS']:
312 extras_dir_list = makePathListAbsolute(main['EXTRAS'].split(':'))
313 else:
314 extras_dir_list = []
315
316 Export('base_dir')
317 Export('extras_dir_list')
318
319 # the ext directory should be on the #includes path
320 main.Append(CPPPATH=[Dir('ext')])
321
322 # Add shared top-level headers
323 main.Prepend(CPPPATH=Dir('include'))
324
325 if GetOption('verbose'):
326 def MakeAction(action, string, *args, **kwargs):
327 return Action(action, *args, **kwargs)
328 else:
329 MakeAction = Action
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")
340 Export('MakeAction')
341
342 # Initialize the Link-Time Optimization (LTO) flags
343 main['LTO_CCFLAGS'] = []
344 main['LTO_LDFLAGS'] = []
345
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'] = []
351
352 CXX_version = readCommand([main['CXX'],'--version'], exception=False)
353 CXX_V = readCommand([main['CXX'],'-V'], exception=False)
354
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?')
359
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'])
374
375 main.Append(LINKFLAGS='-Wl,--as-needed')
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.get('LINKFLAGS')
381 shared_partial_flags = ['-r', '-nostdlib']
382 main.Append(PSHLINKFLAGS=shared_partial_flags)
383 main.Append(PLINKFLAGS=shared_partial_flags)
384
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',
390 ])
391 else:
392 error('\n'.join((
393 "Don't know what compiler options to use for your compiler.",
394 "compiler: " + main['CXX'],
395 "version: " + CXX_version.replace('\n', '<nl>') if
396 CXX_version else 'COMMAND NOT FOUND!',
397 "If you're trying to use a compiler other than GCC",
398 "or clang, there appears to be something wrong with your",
399 "environment.",
400 "",
401 "If you are trying to use a compiler other than those listed",
402 "above you will need to ease fix SConstruct and ",
403 "src/SConscript to support that compiler.")))
404
405 if main['GCC']:
406 # Check for a supported version of gcc. >= 4.8 is chosen for its
407 # level of c++11 support. See
408 # http://gcc.gnu.org/projects/cxx0x.html for details.
409 gcc_version = readCommand([main['CXX'], '-dumpversion'], exception=False)
410 if compareVersions(gcc_version, "4.8") < 0:
411 error('gcc version 4.8 or newer required.\n'
412 'Installed version:', gcc_version)
413 Exit(1)
414
415 main['GCC_VERSION'] = gcc_version
416
417 if compareVersions(gcc_version, '4.9') >= 0:
418 # Incremental linking with LTO is currently broken in gcc versions
419 # 4.9 and above. A version where everything works completely hasn't
420 # yet been identified.
421 #
422 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548
423 main['BROKEN_INCREMENTAL_LTO'] = True
424 if compareVersions(gcc_version, '6.0') >= 0:
425 # gcc versions 6.0 and greater accept an -flinker-output flag which
426 # selects what type of output the linker should generate. This is
427 # necessary for incremental lto to work, but is also broken in
428 # current versions of gcc. It may not be necessary in future
429 # versions. We add it here since it might be, and as a reminder that
430 # it exists. It's excluded if lto is being forced.
431 #
432 # https://gcc.gnu.org/gcc-6/changes.html
433 # https://gcc.gnu.org/ml/gcc-patches/2015-11/msg03161.html
434 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69866
435 if not GetOption('force_lto'):
436 main.Append(PSHLINKFLAGS='-flinker-output=rel')
437 main.Append(PLINKFLAGS='-flinker-output=rel')
438
439 disable_lto = GetOption('no_lto')
440 if not disable_lto and main.get('BROKEN_INCREMENTAL_LTO', False) and \
441 not GetOption('force_lto'):
442 warning('Warning: Your compiler doesn\'t support incremental linking '
443 'and lto at the same time, so lto is being disabled. To force '
444 'lto on anyway, use the --force-lto option. That will disable '
445 'partial linking.')
446 disable_lto = True
447
448 # Add the appropriate Link-Time Optimization (LTO) flags
449 # unless LTO is explicitly turned off. Note that these flags
450 # are only used by the fast target.
451 if not disable_lto:
452 # Pass the LTO flag when compiling to produce GIMPLE
453 # output, we merely create the flags here and only append
454 # them later
455 main['LTO_CCFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
456
457 # Use the same amount of jobs for LTO as we are running
458 # scons with
459 main['LTO_LDFLAGS'] = ['-flto=%d' % GetOption('num_jobs')]
460
461 main.Append(TCMALLOC_CCFLAGS=['-fno-builtin-malloc', '-fno-builtin-calloc',
462 '-fno-builtin-realloc', '-fno-builtin-free'])
463
464 elif main['CLANG']:
465 # Check for a supported version of clang, >= 3.1 is needed to
466 # support similar features as gcc 4.8. See
467 # http://clang.llvm.org/cxx_status.html for details
468 clang_version_re = re.compile(".* version (\d+\.\d+)")
469 clang_version_match = clang_version_re.search(CXX_version)
470 if (clang_version_match):
471 clang_version = clang_version_match.groups()[0]
472 if compareVersions(clang_version, "3.1") < 0:
473 error('clang version 3.1 or newer required.\n'
474 'Installed version:', clang_version)
475 else:
476 error('Unable to determine clang version.')
477
478 # clang has a few additional warnings that we disable, extraneous
479 # parantheses are allowed due to Ruby's printing of the AST,
480 # finally self assignments are allowed as the generated CPU code
481 # is relying on this
482 main.Append(CCFLAGS=['-Wno-parentheses',
483 '-Wno-self-assign',
484 # Some versions of libstdc++ (4.8?) seem to
485 # use struct hash and class hash
486 # interchangeably.
487 '-Wno-mismatched-tags',
488 ])
489
490 main.Append(TCMALLOC_CCFLAGS=['-fno-builtin'])
491
492 # On Mac OS X/Darwin we need to also use libc++ (part of XCode) as
493 # opposed to libstdc++, as the later is dated.
494 if sys.platform == "darwin":
495 main.Append(CXXFLAGS=['-stdlib=libc++'])
496 main.Append(LIBS=['c++'])
497
498 # On FreeBSD we need libthr.
499 if sys.platform.startswith('freebsd'):
500 main.Append(LIBS=['thr'])
501
502 # Add sanitizers flags
503 sanitizers=[]
504 if GetOption('with_ubsan'):
505 # Only gcc >= 4.9 supports UBSan, so check both the version
506 # and the command-line option before adding the compiler and
507 # linker flags.
508 if not main['GCC'] or compareVersions(main['GCC_VERSION'], '4.9') >= 0:
509 sanitizers.append('undefined')
510 if GetOption('with_asan'):
511 # Available for gcc >= 4.8 or llvm >= 3.1 both a requirement
512 # by the build system
513 sanitizers.append('address')
514 if sanitizers:
515 sanitizers = ','.join(sanitizers)
516 if main['GCC'] or main['CLANG']:
517 main.Append(CCFLAGS=['-fsanitize=%s' % sanitizers,
518 '-fno-omit-frame-pointer'],
519 LINKFLAGS='-fsanitize=%s' % sanitizers)
520 else:
521 warning("Don't know how to enable %s sanitizer(s) for your "
522 "compiler." % sanitizers)
523
524 # Set up common yacc/bison flags (needed for Ruby)
525 main['YACCFLAGS'] = '-d'
526 main['YACCHXXFILESUFFIX'] = '.hh'
527
528 # Do this after we save setting back, or else we'll tack on an
529 # extra 'qdo' every time we run scons.
530 if main['BATCH']:
531 main['CC'] = main['BATCH_CMD'] + ' ' + main['CC']
532 main['CXX'] = main['BATCH_CMD'] + ' ' + main['CXX']
533 main['AS'] = main['BATCH_CMD'] + ' ' + main['AS']
534 main['AR'] = main['BATCH_CMD'] + ' ' + main['AR']
535 main['RANLIB'] = main['BATCH_CMD'] + ' ' + main['RANLIB']
536
537 if sys.platform == 'cygwin':
538 # cygwin has some header file issues...
539 main.Append(CCFLAGS=["-Wno-uninitialized"])
540
541
542 have_pkg_config = readCommand(['pkg-config', '--version'], exception='')
543
544 # Check for the protobuf compiler
545 try:
546 main['HAVE_PROTOC'] = True
547 protoc_version = readCommand([main['PROTOC'], '--version']).split()
548
549 # First two words should be "libprotoc x.y.z"
550 if len(protoc_version) < 2 or protoc_version[0] != 'libprotoc':
551 warning('Protocol buffer compiler (protoc) not found.\n'
552 'Please install protobuf-compiler for tracing support.')
553 main['HAVE_PROTOC'] = False
554 else:
555 # Based on the availability of the compress stream wrappers,
556 # require 2.1.0
557 min_protoc_version = '2.1.0'
558 if compareVersions(protoc_version[1], min_protoc_version) < 0:
559 warning('protoc version', min_protoc_version,
560 'or newer required.\n'
561 'Installed version:', protoc_version[1])
562 main['HAVE_PROTOC'] = False
563 else:
564 # Attempt to determine the appropriate include path and
565 # library path using pkg-config, that means we also need to
566 # check for pkg-config. Note that it is possible to use
567 # protobuf without the involvement of pkg-config. Later on we
568 # check go a library config check and at that point the test
569 # will fail if libprotobuf cannot be found.
570 if have_pkg_config:
571 try:
572 # Attempt to establish what linking flags to add for
573 # protobuf
574 # using pkg-config
575 main.ParseConfig(
576 'pkg-config --cflags --libs-only-L protobuf')
577 except:
578 warning('pkg-config could not get protobuf flags.')
579 except Exception as e:
580 warning('While checking protoc version:', str(e))
581 main['HAVE_PROTOC'] = False
582
583 # Check for 'timeout' from GNU coreutils. If present, regressions will
584 # be run with a time limit. We require version 8.13 since we rely on
585 # support for the '--foreground' option.
586 if sys.platform.startswith('freebsd'):
587 timeout_lines = readCommand(['gtimeout', '--version'],
588 exception='').splitlines()
589 else:
590 timeout_lines = readCommand(['timeout', '--version'],
591 exception='').splitlines()
592 # Get the first line and tokenize it
593 timeout_version = timeout_lines[0].split() if timeout_lines else []
594 main['TIMEOUT'] = timeout_version and \
595 compareVersions(timeout_version[-1], '8.13') >= 0
596
597 # Add a custom Check function to test for structure members.
598 def CheckMember(context, include, decl, member, include_quotes="<>"):
599 context.Message("Checking for member %s in %s..." %
600 (member, decl))
601 text = """
602 #include %(header)s
603 int main(){
604 %(decl)s test;
605 (void)test.%(member)s;
606 return 0;
607 };
608 """ % { "header" : include_quotes[0] + include + include_quotes[1],
609 "decl" : decl,
610 "member" : member,
611 }
612
613 ret = context.TryCompile(text, extension=".cc")
614 context.Result(ret)
615 return ret
616
617 # Platform-specific configuration. Note again that we assume that all
618 # builds under a given build root run on the same host platform.
619 conf = Configure(main,
620 conf_dir = joinpath(build_root, '.scons_config'),
621 log_file = joinpath(build_root, 'scons_config.log'),
622 custom_tests = {
623 'CheckMember' : CheckMember,
624 })
625
626 # Check if we should compile a 64 bit binary on Mac OS X/Darwin
627 try:
628 import platform
629 uname = platform.uname()
630 if uname[0] == 'Darwin' and compareVersions(uname[2], '9.0.0') >= 0:
631 if int(readCommand('sysctl -n hw.cpu64bit_capable')[0]):
632 main.Append(CCFLAGS=['-arch', 'x86_64'])
633 main.Append(CFLAGS=['-arch', 'x86_64'])
634 main.Append(LINKFLAGS=['-arch', 'x86_64'])
635 main.Append(ASFLAGS=['-arch', 'x86_64'])
636 except:
637 pass
638
639 # Recent versions of scons substitute a "Null" object for Configure()
640 # when configuration isn't necessary, e.g., if the "--help" option is
641 # present. Unfortuantely this Null object always returns false,
642 # breaking all our configuration checks. We replace it with our own
643 # more optimistic null object that returns True instead.
644 if not conf:
645 def NullCheck(*args, **kwargs):
646 return True
647
648 class NullConf:
649 def __init__(self, env):
650 self.env = env
651 def Finish(self):
652 return self.env
653 def __getattr__(self, mname):
654 return NullCheck
655
656 conf = NullConf(main)
657
658 # Cache build files in the supplied directory.
659 if main['M5_BUILD_CACHE']:
660 print('Using build cache located at', main['M5_BUILD_CACHE'])
661 CacheDir(main['M5_BUILD_CACHE'])
662
663 main['USE_PYTHON'] = not GetOption('without_python')
664 if main['USE_PYTHON']:
665 # Find Python include and library directories for embedding the
666 # interpreter. We rely on python-config to resolve the appropriate
667 # includes and linker flags. ParseConfig does not seem to understand
668 # the more exotic linker flags such as -Xlinker and -export-dynamic so
669 # we add them explicitly below. If you want to link in an alternate
670 # version of python, see above for instructions on how to invoke
671 # scons with the appropriate PATH set.
672
673 python_config = find_first_prog(main['PYTHON_CONFIG'])
674 if python_config is None:
675 error("Can't find a suitable python-config, tried %s" % \
676 main['PYTHON_CONFIG'])
677
678 print("Info: Using Python config: %s" % (python_config, ))
679 py_includes = readCommand([python_config, '--includes'],
680 exception='').split()
681 py_includes = filter(lambda s: match(r'.*\/include\/.*',s), py_includes)
682 # Strip the -I from the include folders before adding them to the
683 # CPPPATH
684 py_includes = map(lambda s: s[2:] if s.startswith('-I') else s, py_includes)
685 main.Append(CPPPATH=py_includes)
686
687 # Read the linker flags and split them into libraries and other link
688 # flags. The libraries are added later through the call the CheckLib.
689 py_ld_flags = readCommand([python_config, '--ldflags'],
690 exception='').split()
691 py_libs = []
692 for lib in py_ld_flags:
693 if not lib.startswith('-l'):
694 main.Append(LINKFLAGS=[lib])
695 else:
696 lib = lib[2:]
697 if lib not in py_libs:
698 py_libs.append(lib)
699
700 # verify that this stuff works
701 if not conf.CheckHeader('Python.h', '<>'):
702 error("Check failed for Python.h header in",
703 ' '.join(py_includes), "\n"
704 "Two possible reasons:\n"
705 "1. Python headers are not installed (You can install the "
706 "package python-dev on Ubuntu and RedHat)\n"
707 "2. SCons is using a wrong C compiler. This can happen if "
708 "CC has the wrong value.\n"
709 "CC = %s" % main['CC'])
710
711 for lib in py_libs:
712 if not conf.CheckLib(lib):
713 error("Can't find library %s required by python." % lib)
714
715 # On Solaris you need to use libsocket for socket ops
716 if not conf.CheckLibWithHeader(None, 'sys/socket.h', 'C++', 'accept(0,0,0);'):
717 if not conf.CheckLibWithHeader('socket', 'sys/socket.h',
718 'C++', 'accept(0,0,0);'):
719 error("Can't find library with socket calls (e.g. accept()).")
720
721 # Check for zlib. If the check passes, libz will be automatically
722 # added to the LIBS environment variable.
723 if not conf.CheckLibWithHeader('z', 'zlib.h', 'C++','zlibVersion();'):
724 error('Did not find needed zlib compression library '
725 'and/or zlib.h header file.\n'
726 'Please install zlib and try again.')
727
728 # If we have the protobuf compiler, also make sure we have the
729 # development libraries. If the check passes, libprotobuf will be
730 # automatically added to the LIBS environment variable. After
731 # this, we can use the HAVE_PROTOBUF flag to determine if we have
732 # got both protoc and libprotobuf available.
733 main['HAVE_PROTOBUF'] = main['HAVE_PROTOC'] and \
734 conf.CheckLibWithHeader('protobuf', 'google/protobuf/message.h',
735 'C++', 'GOOGLE_PROTOBUF_VERIFY_VERSION;')
736
737 # Valgrind gets much less confused if you tell it when you're using
738 # alternative stacks.
739 main['HAVE_VALGRIND'] = conf.CheckCHeader('valgrind/valgrind.h')
740
741 # If we have the compiler but not the library, print another warning.
742 if main['HAVE_PROTOC'] and not main['HAVE_PROTOBUF']:
743 warning('Did not find protocol buffer library and/or headers.\n'
744 'Please install libprotobuf-dev for tracing support.')
745
746 # Check for librt.
747 have_posix_clock = \
748 conf.CheckLibWithHeader(None, 'time.h', 'C',
749 'clock_nanosleep(0,0,NULL,NULL);') or \
750 conf.CheckLibWithHeader('rt', 'time.h', 'C',
751 'clock_nanosleep(0,0,NULL,NULL);')
752
753 have_posix_timers = \
754 conf.CheckLibWithHeader([None, 'rt'], [ 'time.h', 'signal.h' ], 'C',
755 'timer_create(CLOCK_MONOTONIC, NULL, NULL);')
756
757 if not GetOption('without_tcmalloc'):
758 if conf.CheckLib('tcmalloc'):
759 main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
760 elif conf.CheckLib('tcmalloc_minimal'):
761 main.Append(CCFLAGS=main['TCMALLOC_CCFLAGS'])
762 else:
763 warning("You can get a 12% performance improvement by "
764 "installing tcmalloc (libgoogle-perftools-dev package "
765 "on Ubuntu or RedHat).")
766
767
768 # Detect back trace implementations. The last implementation in the
769 # list will be used by default.
770 backtrace_impls = [ "none" ]
771
772 backtrace_checker = 'char temp;' + \
773 ' backtrace_symbols_fd((void*)&temp, 0, 0);'
774 if conf.CheckLibWithHeader(None, 'execinfo.h', 'C', backtrace_checker):
775 backtrace_impls.append("glibc")
776 elif conf.CheckLibWithHeader('execinfo', 'execinfo.h', 'C',
777 backtrace_checker):
778 # NetBSD and FreeBSD need libexecinfo.
779 backtrace_impls.append("glibc")
780 main.Append(LIBS=['execinfo'])
781
782 if backtrace_impls[-1] == "none":
783 default_backtrace_impl = "none"
784 warning("No suitable back trace implementation found.")
785
786 if not have_posix_clock:
787 warning("Can't find library for POSIX clocks.")
788
789 # Check for <fenv.h> (C99 FP environment control)
790 have_fenv = conf.CheckHeader('fenv.h', '<>')
791 if not have_fenv:
792 warning("Header file <fenv.h> not found.\n"
793 "This host has no IEEE FP rounding mode control.")
794
795 # Check for <png.h> (libpng library needed if wanting to dump
796 # frame buffer image in png format)
797 have_png = conf.CheckHeader('png.h', '<>')
798 if not have_png:
799 warning("Header file <png.h> not found.\n"
800 "This host has no libpng library.\n"
801 "Disabling support for PNG framebuffers.")
802
803 # Check if we should enable KVM-based hardware virtualization. The API
804 # we rely on exists since version 2.6.36 of the kernel, but somehow
805 # the KVM_API_VERSION does not reflect the change. We test for one of
806 # the types as a fall back.
807 have_kvm = conf.CheckHeader('linux/kvm.h', '<>')
808 if not have_kvm:
809 print("Info: Compatible header file <linux/kvm.h> not found, "
810 "disabling KVM support.")
811
812 # Check if the TUN/TAP driver is available.
813 have_tuntap = conf.CheckHeader('linux/if_tun.h', '<>')
814 if not have_tuntap:
815 print("Info: Compatible header file <linux/if_tun.h> not found.")
816
817 # x86 needs support for xsave. We test for the structure here since we
818 # won't be able to run new tests by the time we know which ISA we're
819 # targeting.
820 have_kvm_xsave = conf.CheckTypeSize('struct kvm_xsave',
821 '#include <linux/kvm.h>') != 0
822
823 # Check if the requested target ISA is compatible with the host
824 def is_isa_kvm_compatible(isa):
825 try:
826 import platform
827 host_isa = platform.machine()
828 except:
829 warning("Failed to determine host ISA.")
830 return False
831
832 if not have_posix_timers:
833 warning("Can not enable KVM, host seems to lack support "
834 "for POSIX timers")
835 return False
836
837 if isa == "arm":
838 return host_isa in ( "armv7l", "aarch64" )
839 elif isa == "x86":
840 if host_isa != "x86_64":
841 return False
842
843 if not have_kvm_xsave:
844 warning("KVM on x86 requires xsave support in kernel headers.")
845 return False
846
847 return True
848 else:
849 return False
850
851
852 # Check if the exclude_host attribute is available. We want this to
853 # get accurate instruction counts in KVM.
854 main['HAVE_PERF_ATTR_EXCLUDE_HOST'] = conf.CheckMember(
855 'linux/perf_event.h', 'struct perf_event_attr', 'exclude_host')
856
857 def check_hdf5():
858 return \
859 conf.CheckLibWithHeader('hdf5', 'hdf5.h', 'C',
860 'H5Fcreate("", 0, 0, 0);') and \
861 conf.CheckLibWithHeader('hdf5_cpp', 'H5Cpp.h', 'C++',
862 'H5::H5File("", 0);')
863
864 def check_hdf5_pkg(name):
865 print("Checking for %s using pkg-config..." % name, end="")
866 if not have_pkg_config:
867 print(" pkg-config not found")
868 return False
869
870 try:
871 main.ParseConfig('pkg-config --cflags-only-I --libs-only-L %s' % name)
872 print(" yes")
873 return True
874 except:
875 print(" no")
876 return False
877
878 # Check if there is a pkg-config configuration for hdf5. If we find
879 # it, setup the environment to enable linking and header inclusion. We
880 # don't actually try to include any headers or link with hdf5 at this
881 # stage.
882 if not check_hdf5_pkg('hdf5-serial'):
883 check_hdf5_pkg('hdf5')
884
885 # Check if the HDF5 libraries can be found. This check respects the
886 # include path and library path provided by pkg-config. We perform
887 # this check even if there isn't a pkg-config configuration for hdf5
888 # since some installations don't use pkg-config.
889 have_hdf5 = check_hdf5()
890 if not have_hdf5:
891 print("Warning: Couldn't find any HDF5 C++ libraries. Disabling")
892 print(" HDF5 support.")
893
894 ######################################################################
895 #
896 # Finish the configuration
897 #
898 main = conf.Finish()
899
900 ######################################################################
901 #
902 # Collect all non-global variables
903 #
904
905 # Define the universe of supported ISAs
906 all_isa_list = [ ]
907 all_gpu_isa_list = [ ]
908 Export('all_isa_list')
909 Export('all_gpu_isa_list')
910
911 class CpuModel(object):
912 '''The CpuModel class encapsulates everything the ISA parser needs to
913 know about a particular CPU model.'''
914
915 # Dict of available CPU model objects. Accessible as CpuModel.dict.
916 dict = {}
917
918 # Constructor. Automatically adds models to CpuModel.dict.
919 def __init__(self, name, default=False):
920 self.name = name # name of model
921
922 # This cpu is enabled by default
923 self.default = default
924
925 # Add self to dict
926 if name in CpuModel.dict:
927 raise AttributeError("CpuModel '%s' already registered" % name)
928 CpuModel.dict[name] = self
929
930 Export('CpuModel')
931
932 # Sticky variables get saved in the variables file so they persist from
933 # one invocation to the next (unless overridden, in which case the new
934 # value becomes sticky).
935 sticky_vars = Variables(args=ARGUMENTS)
936 Export('sticky_vars')
937
938 # Sticky variables that should be exported
939 export_vars = []
940 Export('export_vars')
941
942 # For Ruby
943 all_protocols = []
944 Export('all_protocols')
945 protocol_dirs = []
946 Export('protocol_dirs')
947 slicc_includes = []
948 Export('slicc_includes')
949
950 # Walk the tree and execute all SConsopts scripts that wil add to the
951 # above variables
952 if GetOption('verbose'):
953 print("Reading SConsopts")
954 for bdir in [ base_dir ] + extras_dir_list:
955 if not isdir(bdir):
956 error("Directory '%s' does not exist." % bdir)
957 for root, dirs, files in os.walk(bdir):
958 if 'SConsopts' in files:
959 if GetOption('verbose'):
960 print("Reading", joinpath(root, 'SConsopts'))
961 SConscript(joinpath(root, 'SConsopts'))
962
963 all_isa_list.sort()
964 all_gpu_isa_list.sort()
965
966 sticky_vars.AddVariables(
967 EnumVariable('TARGET_ISA', 'Target ISA', 'alpha', all_isa_list),
968 EnumVariable('TARGET_GPU_ISA', 'Target GPU ISA', 'hsail', all_gpu_isa_list),
969 ListVariable('CPU_MODELS', 'CPU models',
970 sorted(n for n,m in CpuModel.dict.iteritems() if m.default),
971 sorted(CpuModel.dict.keys())),
972 BoolVariable('EFENCE', 'Link with Electric Fence malloc debugger',
973 False),
974 BoolVariable('SS_COMPATIBLE_FP',
975 'Make floating-point results compatible with SimpleScalar',
976 False),
977 BoolVariable('USE_SSE2',
978 'Compile for SSE2 (-msse2) to get IEEE FP on x86 hosts',
979 False),
980 BoolVariable('USE_POSIX_CLOCK', 'Use POSIX Clocks', have_posix_clock),
981 BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
982 BoolVariable('USE_PNG', 'Enable support for PNG images', have_png),
983 BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability',
984 False),
985 BoolVariable('USE_KVM', 'Enable hardware virtualized (KVM) CPU models',
986 have_kvm),
987 BoolVariable('USE_TUNTAP',
988 'Enable using a tap device to bridge to the host network',
989 have_tuntap),
990 BoolVariable('BUILD_GPU', 'Build the compute-GPU model', False),
991 EnumVariable('PROTOCOL', 'Coherence protocol for Ruby', 'None',
992 all_protocols),
993 EnumVariable('BACKTRACE_IMPL', 'Post-mortem dump implementation',
994 backtrace_impls[-1], backtrace_impls),
995 ('NUMBER_BITS_PER_SET', 'Max elements in set (default 64)',
996 64),
997 BoolVariable('USE_HDF5', 'Enable the HDF5 support', have_hdf5),
998 )
999
1000 # These variables get exported to #defines in config/*.hh (see src/SConscript).
1001 export_vars += ['USE_FENV', 'SS_COMPATIBLE_FP', 'TARGET_ISA', 'TARGET_GPU_ISA',
1002 'CP_ANNOTATE', 'USE_POSIX_CLOCK', 'USE_KVM', 'USE_TUNTAP',
1003 'PROTOCOL', 'HAVE_PROTOBUF', 'HAVE_VALGRIND',
1004 'HAVE_PERF_ATTR_EXCLUDE_HOST', 'USE_PNG',
1005 'NUMBER_BITS_PER_SET', 'USE_HDF5']
1006
1007 ###################################################
1008 #
1009 # Define a SCons builder for configuration flag headers.
1010 #
1011 ###################################################
1012
1013 # This function generates a config header file that #defines the
1014 # variable symbol to the current variable setting (0 or 1). The source
1015 # operands are the name of the variable and a Value node containing the
1016 # value of the variable.
1017 def build_config_file(target, source, env):
1018 (variable, value) = [s.get_contents() for s in source]
1019 f = file(str(target[0]), 'w')
1020 print('#define', variable, value, file=f)
1021 f.close()
1022 return None
1023
1024 # Combine the two functions into a scons Action object.
1025 config_action = MakeAction(build_config_file, Transform("CONFIG H", 2))
1026
1027 # The emitter munges the source & target node lists to reflect what
1028 # we're really doing.
1029 def config_emitter(target, source, env):
1030 # extract variable name from Builder arg
1031 variable = str(target[0])
1032 # True target is config header file
1033 target = joinpath('config', variable.lower() + '.hh')
1034 val = env[variable]
1035 if isinstance(val, bool):
1036 # Force value to 0/1
1037 val = int(val)
1038 elif isinstance(val, str):
1039 val = '"' + val + '"'
1040
1041 # Sources are variable name & value (packaged in SCons Value nodes)
1042 return ([target], [Value(variable), Value(val)])
1043
1044 config_builder = Builder(emitter = config_emitter, action = config_action)
1045
1046 main.Append(BUILDERS = { 'ConfigFile' : config_builder })
1047
1048 ###################################################
1049 #
1050 # Builders for static and shared partially linked object files.
1051 #
1052 ###################################################
1053
1054 partial_static_builder = Builder(action=SCons.Defaults.LinkAction,
1055 src_suffix='$OBJSUFFIX',
1056 src_builder=['StaticObject', 'Object'],
1057 LINKFLAGS='$PLINKFLAGS',
1058 LIBS='')
1059
1060 def partial_shared_emitter(target, source, env):
1061 for tgt in target:
1062 tgt.attributes.shared = 1
1063 return (target, source)
1064 partial_shared_builder = Builder(action=SCons.Defaults.ShLinkAction,
1065 emitter=partial_shared_emitter,
1066 src_suffix='$SHOBJSUFFIX',
1067 src_builder='SharedObject',
1068 SHLINKFLAGS='$PSHLINKFLAGS',
1069 LIBS='')
1070
1071 main.Append(BUILDERS = { 'PartialShared' : partial_shared_builder,
1072 'PartialStatic' : partial_static_builder })
1073
1074 def add_local_rpath(env, *targets):
1075 '''Set up an RPATH for a library which lives in the build directory.
1076
1077 The construction environment variable BIN_RPATH_PREFIX should be set to
1078 the relative path of the build directory starting from the location of the
1079 binary.'''
1080 for target in targets:
1081 target = env.Entry(target)
1082 if not isinstance(target, SCons.Node.FS.Dir):
1083 target = target.dir
1084 relpath = os.path.relpath(target.abspath, env['BUILDDIR'])
1085 components = [
1086 '\\$$ORIGIN',
1087 '${BIN_RPATH_PREFIX}',
1088 relpath
1089 ]
1090 env.Append(RPATH=[env.Literal(os.path.join(*components))])
1091
1092 if sys.platform != "darwin":
1093 main.Append(LINKFLAGS=Split('-z origin'))
1094
1095 main.AddMethod(add_local_rpath, 'AddLocalRPATH')
1096
1097 # builds in ext are shared across all configs in the build root.
1098 ext_dir = abspath(joinpath(str(main.root), 'ext'))
1099 ext_build_dirs = []
1100 for root, dirs, files in os.walk(ext_dir):
1101 if 'SConscript' in files:
1102 build_dir = os.path.relpath(root, ext_dir)
1103 ext_build_dirs.append(build_dir)
1104 main.SConscript(joinpath(root, 'SConscript'),
1105 variant_dir=joinpath(build_root, build_dir))
1106
1107 gdb_xml_dir = joinpath(ext_dir, 'gdb-xml')
1108 Export('gdb_xml_dir')
1109
1110 main.Prepend(CPPPATH=Dir('ext/pybind11/include/'))
1111
1112 ###################################################
1113 #
1114 # This builder and wrapper method are used to set up a directory with
1115 # switching headers. Those are headers which are in a generic location and
1116 # that include more specific headers from a directory chosen at build time
1117 # based on the current build settings.
1118 #
1119 ###################################################
1120
1121 def build_switching_header(target, source, env):
1122 path = str(target[0])
1123 subdir = str(source[0])
1124 dp, fp = os.path.split(path)
1125 dp = os.path.relpath(os.path.realpath(dp),
1126 os.path.realpath(env['BUILDDIR']))
1127 with open(path, 'w') as hdr:
1128 print('#include "%s/%s/%s"' % (dp, subdir, fp), file=hdr)
1129
1130 switching_header_action = MakeAction(build_switching_header,
1131 Transform('GENERATE'))
1132
1133 switching_header_builder = Builder(action=switching_header_action,
1134 source_factory=Value,
1135 single_source=True)
1136
1137 main.Append(BUILDERS = { 'SwitchingHeader': switching_header_builder })
1138
1139 def switching_headers(self, headers, source):
1140 for header in headers:
1141 self.SwitchingHeader(header, source)
1142
1143 main.AddMethod(switching_headers, 'SwitchingHeaders')
1144
1145 ###################################################
1146 #
1147 # Define build environments for selected configurations.
1148 #
1149 ###################################################
1150
1151 for variant_path in variant_paths:
1152 if not GetOption('silent'):
1153 print("Building in", variant_path)
1154
1155 # Make a copy of the build-root environment to use for this config.
1156 env = main.Clone()
1157 env['BUILDDIR'] = variant_path
1158
1159 # variant_dir is the tail component of build path, and is used to
1160 # determine the build parameters (e.g., 'ALPHA_SE')
1161 (build_root, variant_dir) = splitpath(variant_path)
1162
1163 # Set env variables according to the build directory config.
1164 sticky_vars.files = []
1165 # Variables for $BUILD_ROOT/$VARIANT_DIR are stored in
1166 # $BUILD_ROOT/variables/$VARIANT_DIR so you can nuke
1167 # $BUILD_ROOT/$VARIANT_DIR without losing your variables settings.
1168 current_vars_file = joinpath(build_root, 'variables', variant_dir)
1169 if isfile(current_vars_file):
1170 sticky_vars.files.append(current_vars_file)
1171 if not GetOption('silent'):
1172 print("Using saved variables file %s" % current_vars_file)
1173 elif variant_dir in ext_build_dirs:
1174 # Things in ext are built without a variant directory.
1175 continue
1176 else:
1177 # Build dir-specific variables file doesn't exist.
1178
1179 # Make sure the directory is there so we can create it later
1180 opt_dir = dirname(current_vars_file)
1181 if not isdir(opt_dir):
1182 mkdir(opt_dir)
1183
1184 # Get default build variables from source tree. Variables are
1185 # normally determined by name of $VARIANT_DIR, but can be
1186 # overridden by '--default=' arg on command line.
1187 default = GetOption('default')
1188 opts_dir = joinpath(main.root.abspath, 'build_opts')
1189 if default:
1190 default_vars_files = [joinpath(build_root, 'variables', default),
1191 joinpath(opts_dir, default)]
1192 else:
1193 default_vars_files = [joinpath(opts_dir, variant_dir)]
1194 existing_files = filter(isfile, default_vars_files)
1195 if existing_files:
1196 default_vars_file = existing_files[0]
1197 sticky_vars.files.append(default_vars_file)
1198 print("Variables file %s not found,\n using defaults in %s"
1199 % (current_vars_file, default_vars_file))
1200 else:
1201 error("Cannot find variables file %s or default file(s) %s"
1202 % (current_vars_file, ' or '.join(default_vars_files)))
1203 Exit(1)
1204
1205 # Apply current variable settings to env
1206 sticky_vars.Update(env)
1207
1208 help_texts["local_vars"] += \
1209 "Build variables for %s:\n" % variant_dir \
1210 + sticky_vars.GenerateHelpText(env)
1211
1212 # Process variable settings.
1213
1214 if not have_fenv and env['USE_FENV']:
1215 warning("<fenv.h> not available; forcing USE_FENV to False in",
1216 variant_dir + ".")
1217 env['USE_FENV'] = False
1218
1219 if not env['USE_FENV']:
1220 warning("No IEEE FP rounding mode control in", variant_dir + ".\n"
1221 "FP results may deviate slightly from other platforms.")
1222
1223 if not have_png and env['USE_PNG']:
1224 warning("<png.h> not available; forcing USE_PNG to False in",
1225 variant_dir + ".")
1226 env['USE_PNG'] = False
1227
1228 if env['USE_PNG']:
1229 env.Append(LIBS=['png'])
1230
1231 if env['EFENCE']:
1232 env.Append(LIBS=['efence'])
1233
1234 if env['USE_KVM']:
1235 if not have_kvm:
1236 warning("Can not enable KVM, host seems to lack KVM support")
1237 env['USE_KVM'] = False
1238 elif not is_isa_kvm_compatible(env['TARGET_ISA']):
1239 print("Info: KVM support disabled due to unsupported host and "
1240 "target ISA combination")
1241 env['USE_KVM'] = False
1242
1243 if env['USE_TUNTAP']:
1244 if not have_tuntap:
1245 warning("Can't connect EtherTap with a tap device.")
1246 env['USE_TUNTAP'] = False
1247
1248 if env['BUILD_GPU']:
1249 env.Append(CPPDEFINES=['BUILD_GPU'])
1250
1251 # Warn about missing optional functionality
1252 if env['USE_KVM']:
1253 if not main['HAVE_PERF_ATTR_EXCLUDE_HOST']:
1254 warning("perf_event headers lack support for the exclude_host "
1255 "attribute. KVM instruction counts will be inaccurate.")
1256
1257 # Save sticky variable settings back to current variables file
1258 sticky_vars.Save(current_vars_file, env)
1259
1260 if env['USE_SSE2']:
1261 env.Append(CCFLAGS=['-msse2'])
1262
1263 env.Append(CCFLAGS='$CCFLAGS_EXTRA')
1264 env.Append(LINKFLAGS='$LDFLAGS_EXTRA')
1265
1266 # The src/SConscript file sets up the build rules in 'env' according
1267 # to the configured variables. It returns a list of environments,
1268 # one for each variant build (debug, opt, etc.)
1269 SConscript('src/SConscript', variant_dir = variant_path, exports = 'env')
1270
1271 # base help text
1272 Help('''
1273 Usage: scons [scons options] [build variables] [target(s)]
1274
1275 Extra scons options:
1276 %(options)s
1277
1278 Global build variables:
1279 %(global_vars)s
1280
1281 %(local_vars)s
1282 ''' % help_texts)