aboutsummaryrefslogtreecommitdiff
path: root/mesonbuild/environment.py
blob: 404ed3ee1ffe3cd6d1569a0a6120b8dbac35e968 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
# Copyright 2012-2016 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import os, re, subprocess, platform
from . import coredata, mesonlib
from .compilers import *
import configparser

build_filename = 'meson.build'

class EnvironmentException(mesonlib.MesonException):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

def find_coverage_tools():
    gcovr_exe = 'gcovr'
    lcov_exe = 'lcov'
    genhtml_exe = 'genhtml'

    if not mesonlib.exe_exists([gcovr_exe, '--version']):
        gcovr_exe = None
    if not mesonlib.exe_exists([lcov_exe, '--version']):
        lcov_exe = None
    if not mesonlib.exe_exists([genhtml_exe, '--version']):
        genhtml_exe = None
    return (gcovr_exe, lcov_exe, genhtml_exe)

def find_valgrind():
    valgrind_exe = 'valgrind'
    if not mesonlib.exe_exists([valgrind_exe, '--version']):
        valgrind_exe = None
    return valgrind_exe

def detect_ninja():
    for n in ['ninja', 'ninja-build']:
        try:
            p = subprocess.Popen([n, '--version'], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
        except FileNotFoundError:
            continue
        version = p.communicate()[0].decode(errors='ignore')
        # Perhaps we should add a way for the caller to know the failure mode
        # (not found or too old)
        if p.returncode == 0 and mesonlib.version_compare(version, ">=1.6"):
            return n

def detect_cpu_family():
    """
    Python is inconsistent in its platform module.
    It returns different values for the same cpu.
    For x86 it might return 'x86', 'i686' or somesuch.
    Do some canonicalization.
    """
    trial = platform.machine().lower()
    if trial.startswith('i') and trial.endswith('86'):
        return 'x86'
    if trial.startswith('arm'):
        return 'arm'
    if trial == 'amd64':
        return 'x86_64'
    # Add fixes here as bugs are reported.
    return trial

def detect_cpu():
    trial = platform.machine().lower()
    if trial == 'amd64':
        return 'x86_64'
    # Add fixes here as bugs are reported.
    return trial

def detect_system():
    return platform.system().lower()


def for_windows(is_cross, env):
    """
    Host machine is windows?

    Note: 'host' is the machine on which compiled binaries will run
    """
    if not is_cross:
        return mesonlib.is_windows()
    elif env.cross_info.has_host():
        return env.cross_info.config['host_machine']['system'] == 'windows'
    return False

def for_darwin(is_cross, env):
    """
    Host machine is Darwin (iOS/OS X)?

    Note: 'host' is the machine on which compiled binaries will run
    """
    if not is_cross:
        return mesonlib.is_osx()
    elif env.cross_info.has_host():
        return env.cross_info.config['host_machine']['system'] == 'darwin'
    return False


class Environment():
    private_dir = 'meson-private'
    log_dir = 'meson-logs'
    coredata_file = os.path.join(private_dir, 'coredata.dat')
    version_regex = '\d+(\.\d+)+(-[a-zA-Z0-9]+)?'

    def __init__(self, source_dir, build_dir, main_script_file, options, original_cmd_line_args):
        assert(os.path.isabs(main_script_file))
        assert(not os.path.islink(main_script_file))
        self.source_dir = source_dir
        self.build_dir = build_dir
        self.meson_script_file = main_script_file
        self.scratch_dir = os.path.join(build_dir, Environment.private_dir)
        self.log_dir = os.path.join(build_dir, Environment.log_dir)
        os.makedirs(self.scratch_dir, exist_ok=True)
        os.makedirs(self.log_dir, exist_ok=True)
        try:
            cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
            self.coredata = coredata.load(cdf)
            self.first_invocation = False
        except FileNotFoundError:
            # WARNING: Don't use any values from coredata in __init__. It gets
            # re-initialized with project options by the interpreter during
            # build file parsing.
            self.coredata = coredata.CoreData(options)
            self.coredata.meson_script_file = self.meson_script_file
            self.first_invocation = True
        if self.coredata.cross_file:
            self.cross_info = CrossBuildInfo(self.coredata.cross_file)
        else:
            self.cross_info = None
        self.cmd_line_options = options
        self.original_cmd_line_args = original_cmd_line_args

        # List of potential compilers.
        if mesonlib.is_windows():
            self.default_c = ['cl', 'cc', 'gcc', 'clang']
            self.default_cpp = ['cl', 'c++', 'g++', 'clang++']
        else:
            self.default_c = ['cc']
            self.default_cpp = ['c++']
        self.default_objc = ['cc']
        self.default_objcpp = ['c++']
        self.default_fortran = ['gfortran', 'g95', 'f95', 'f90', 'f77']
        self.default_static_linker = 'ar'
        self.vs_static_linker = 'lib'

        # Various prefixes and suffixes for import libraries, shared libraries,
        # static libraries, and executables.
        # Versioning is added to these names in the backends as-needed.
        cross = self.is_cross_build()
        if (not cross and mesonlib.is_windows()) \
        or (cross and self.cross_info.has_host() and self.cross_info.config['host_machine']['system'] == 'windows'):
            self.exe_suffix = 'exe'
            self.object_suffix = 'obj'
            self.win_libdir_layout = True
        else:
            self.exe_suffix = ''
            self.object_suffix = 'o'
            self.win_libdir_layout = False

    def is_cross_build(self):
        return self.cross_info is not None

    def dump_coredata(self, mtime):
        cdf = os.path.join(self.get_build_dir(), Environment.coredata_file)
        coredata.save(self.coredata, cdf)
        os.utime(cdf, times=(mtime, mtime))

    def get_script_dir(self):
        import mesonbuild.scripts
        return os.path.dirname(mesonbuild.scripts.__file__)

    def get_log_dir(self):
        return self.log_dir

    def get_coredata(self):
        return self.coredata

    def get_build_command(self):
        return self.meson_script_file

    def is_header(self, fname):
        return is_header(fname)

    def is_source(self, fname):
        return is_source(fname)

    def is_object(self, fname):
        return is_object(fname)

    def is_library(self, fname):
        return is_library(fname)

    def had_argument_for(self, option):
        trial1 = '--' + option
        trial2 = '-D' + option
        previous_is_plaind = False
        for i in self.original_cmd_line_args:
            if i.startswith(trial1) or i.startswith(trial2):
                return True
            if previous_is_plaind and i.startswith(option):
                return True
            previous_is_plaind = i == '-D'
        return False

    def merge_options(self, options):
        for (name, value) in options.items():
            if name not in self.coredata.user_options:
                self.coredata.user_options[name] = value
            else:
                oldval = self.coredata.user_options[name]
                if type(oldval) != type(value):
                    self.coredata.user_options[name] = value

    def detect_c_compiler(self, want_cross):
        evar = 'CC'
        if self.is_cross_build() and want_cross:
            compilers = [self.cross_info.config['binaries']['c']]
            ccache = []
            is_cross = True
            if self.cross_info.need_exe_wrapper():
                exe_wrap = self.cross_info.config['binaries'].get('exe_wrapper', None)
            else:
                exe_wrap = []
        elif evar in os.environ:
            compilers = os.environ[evar].split()
            ccache = []
            is_cross = False
            exe_wrap = None
        else:
            compilers = self.default_c
            ccache = self.detect_ccache()
            is_cross = False
            exe_wrap = None
        popen_exceptions = {}
        for compiler in compilers:
            try:
                basename = os.path.basename(compiler).lower()
                if basename == 'cl' or basename == 'cl.exe':
                    arg = '/?'
                else:
                    arg = '--version'
                p = subprocess.Popen([compiler, arg], stdout=subprocess.PIPE,
                                     stderr=subprocess.PIPE)
            except OSError as e:
                popen_exceptions[' '.join([compiler, arg])] = e
                continue
            (out, err) = p.communicate()
            out = out.decode(errors='ignore')
            err = err.decode(errors='ignore')
            vmatch = re.search(Environment.version_regex, out)
            if vmatch:
                version = vmatch.group(0)
            else:
                version = 'unknown version'
            if 'apple' in out and 'Free Software Foundation' in out:
                return GnuCCompiler(ccache + [compiler], version, GCC_OSX, is_cross, exe_wrap)
            if (out.startswith('cc') or 'gcc' in out.lower()) and \
                'Free Software Foundation' in out:
                lowerout = out.lower()
                if 'mingw' in lowerout or 'msys' in lowerout or 'mingw' in compiler.lower():
                    gtype = GCC_MINGW
                else:
                    gtype = GCC_STANDARD
                return GnuCCompiler(ccache + [compiler], version, gtype, is_cross, exe_wrap)
            if 'clang' in out:
                if 'Apple' in out:
                    cltype = CLANG_OSX
                else:
                    cltype = CLANG_STANDARD
                return ClangCCompiler(ccache + [compiler], version, cltype, is_cross, exe_wrap)
            if 'Microsoft' in out or 'Microsoft' in err:
                # Visual Studio prints version number to stderr but
                # everything else to stdout. Why? Lord only knows.
                version = re.search(Environment.version_regex, err).group()
                return VisualStudioCCompiler([compiler], version, is_cross, exe_wrap)
        errmsg = 'Unknown compiler(s): "' + ', '.join(compilers) + '"'
        if popen_exceptions:
            errmsg += '\nThe follow exceptions were encountered:'
            for (c, e) in popen_exceptions.items():
                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
        raise EnvironmentException(errmsg)

    def detect_fortran_compiler(self, want_cross):
        evar = 'FC'
        if self.is_cross_build() and want_cross:
            compilers = [self.cross_info['fortran']]
            is_cross = True
            if self.cross_info.need_exe_wrapper():
                exe_wrap = self.cross_info.get('exe_wrapper', None)
            else:
                exe_wrap = []
        elif evar in os.environ:
            compilers = os.environ[evar].split()
            is_cross = False
            exe_wrap = None
        else:
            compilers = self.default_fortran
            is_cross = False
            exe_wrap = None
        popen_exceptions = {}
        for compiler in compilers:
            for arg in ['--version', '-V']:
                try:
                    p = subprocess.Popen([compiler, arg],
                                         stdout=subprocess.PIPE,
                                         stderr=subprocess.PIPE)
                except OSError as e:
                    popen_exceptions[' '.join([compiler, arg])] = e
                    continue
                (out, err) = p.communicate()
                out = out.decode(errors='ignore')
                err = err.decode(errors='ignore')

                version = 'unknown version'
                vmatch = re.search(Environment.version_regex, out)
                if vmatch:
                    version = vmatch.group(0)

                if 'GNU Fortran' in out:
                    if mesonlib.is_osx():
                        gcctype = GCC_OSX
                    elif mesonlib.is_windows():
                        gcctype = GCC_MINGW
                    else:
                        gcctype = GCC_STANDARD
                    return GnuFortranCompiler([compiler], version, gcctype, is_cross, exe_wrap)

                if 'G95' in out:
                    return G95FortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'Sun Fortran' in err:
                    version = 'unknown version'
                    vmatch = re.search(Environment.version_regex, err)
                    if vmatch:
                        version = vmatch.group(0)
                    return SunFortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'ifort (IFORT)' in out:
                    return IntelFortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'PathScale EKOPath(tm)' in err:
                    return PathScaleFortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'pgf90' in out:
                    return PGIFortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'Open64 Compiler Suite' in err:
                    return Open64FortranCompiler([compiler], version, is_cross, exe_wrap)

                if 'NAG Fortran' in err:
                    return NAGFortranCompiler([compiler], version, is_cross, exe_wrap)
        errmsg = 'Unknown compiler(s): "' + ', '.join(compilers) + '"'
        if popen_exceptions:
            errmsg += '\nThe follow exceptions were encountered:'
            for (c, e) in popen_exceptions.items():
                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
        raise EnvironmentException(errmsg)

    def get_scratch_dir(self):
        return self.scratch_dir

    def get_depfixer(self):
        path = os.path.split(__file__)[0]
        return os.path.join(path, 'depfixer.py')

    def detect_cpp_compiler(self, want_cross):
        evar = 'CXX'
        if self.is_cross_build() and want_cross:
            compilers = [self.cross_info.config['binaries']['cpp']]
            ccache = []
            is_cross = True
            if self.cross_info.need_exe_wrapper():
                exe_wrap = self.cross_info.config['binaries'].get('exe_wrapper', None)
            else:
                exe_wrap = []
        elif evar in os.environ:
            compilers = os.environ[evar].split()
            ccache = []
            is_cross = False
            exe_wrap = None
        else:
            compilers = self.default_cpp
            ccache = self.detect_ccache()
            is_cross = False
            exe_wrap = None
        popen_exceptions = {}
        for compiler in compilers:
            basename = os.path.basename(compiler).lower()
            if basename == 'cl' or basename == 'cl.exe':
                arg = '/?'
            else:
                arg = '--version'
            try:
                p = subprocess.Popen([compiler, arg],
                                     stdout=subprocess.PIPE,
                                     stderr=subprocess.PIPE)
            except OSError as e:
                popen_exceptions[' '.join([compiler, arg])] = e
                continue
            (out, err) = p.communicate()
            out = out.decode(errors='ignore')
            err = err.decode(errors='ignore')
            vmatch = re.search(Environment.version_regex, out)
            if vmatch:
                version = vmatch.group(0)
            else:
                version = 'unknown version'
            if 'apple' in out and 'Free Software Foundation' in out:
                return GnuCPPCompiler(ccache + [compiler], version, GCC_OSX, is_cross, exe_wrap)
            if (out.startswith('c++ ') or 'g++' in out or 'GCC' in out) and \
                'Free Software Foundation' in out:
                lowerout = out.lower()
                if 'mingw' in lowerout or 'msys' in lowerout or 'mingw' in compiler.lower():
                    gtype = GCC_MINGW
                else:
                    gtype = GCC_STANDARD
                return GnuCPPCompiler(ccache + [compiler], version, gtype, is_cross, exe_wrap)
            if 'clang' in out:
                if 'Apple' in out:
                    cltype = CLANG_OSX
                else:
                    cltype = CLANG_STANDARD
                return ClangCPPCompiler(ccache + [compiler], version, cltype, is_cross, exe_wrap)
            if 'Microsoft' in out or 'Microsoft' in err:
                version = re.search(Environment.version_regex, err).group()
                return VisualStudioCPPCompiler([compiler], version, is_cross, exe_wrap)
        errmsg = 'Unknown compiler(s): "' + ', '.join(compilers) + '"'
        if popen_exceptions:
            errmsg += '\nThe follow exceptions were encountered:'
            for (c, e) in popen_exceptions.items():
                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
        raise EnvironmentException(errmsg)

    def detect_objc_compiler(self, want_cross):
        if self.is_cross_build() and want_cross:
            exelist = [self.cross_info['objc']]
            is_cross = True
            if self.cross_info.need_exe_wrapper():
                exe_wrap = self.cross_info.get('exe_wrapper', None)
            else:
                exe_wrap = []
        else:
            exelist = self.get_objc_compiler_exelist()
            is_cross = False
            exe_wrap = None
        try:
            p = subprocess.Popen(exelist + ['--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute ObjC compiler "%s"' % ' '.join(exelist))
        (out, err) = p.communicate()
        out = out.decode(errors='ignore')
        err = err.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, out)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if (out.startswith('cc ') or 'gcc' in out) and \
            'Free Software Foundation' in out:
            return GnuObjCCompiler(exelist, version, is_cross, exe_wrap)
        if out.startswith('Apple LLVM'):
            return ClangObjCCompiler(exelist, version, CLANG_OSX, is_cross, exe_wrap)
        if 'apple' in out and 'Free Software Foundation' in out:
            return GnuObjCCompiler(exelist, version, is_cross, exe_wrap)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_objcpp_compiler(self, want_cross):
        if self.is_cross_build() and want_cross:
            exelist = [self.cross_info['objcpp']]
            is_cross = True
            if self.cross_info.need_exe_wrapper():
                exe_wrap = self.cross_info.get('exe_wrapper', None)
            else:
                exe_wrap = []
        else:
            exelist = self.get_objcpp_compiler_exelist()
            is_cross = False
            exe_wrap = None
        try:
            p = subprocess.Popen(exelist + ['--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute ObjC++ compiler "%s"' % ' '.join(exelist))
        (out, err) = p.communicate()
        out = out.decode(errors='ignore')
        err = err.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, out)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if (out.startswith('c++ ') or out.startswith('g++')) and \
            'Free Software Foundation' in out:
            return GnuObjCPPCompiler(exelist, version, is_cross, exe_wrap)
        if out.startswith('Apple LLVM'):
            return ClangObjCPPCompiler(exelist, version, CLANG_OSX, is_cross, exe_wrap)
        if 'apple' in out and 'Free Software Foundation' in out:
            return GnuObjCPPCompiler(exelist, version, is_cross, exe_wrap)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_java_compiler(self):
        exelist = ['javac']
        try:
            p = subprocess.Popen(exelist + ['-version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute Java compiler "%s"' % ' '.join(exelist))
        (out, err) = p.communicate()
        out = out.decode(errors='ignore')
        err = err.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, err)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if 'javac' in err:
            return JavaCompiler(exelist, version)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_cs_compiler(self):
        exelist = ['mcs']
        try:
            p = subprocess.Popen(exelist + ['--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute C# compiler "%s"' % ' '.join(exelist))
        (out, err) = p.communicate()
        out = out.decode(errors='ignore')
        err = err.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, out)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if 'Mono' in out:
            return MonoCompiler(exelist, version)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_vala_compiler(self):
        exelist = ['valac']
        try:
            p = subprocess.Popen(exelist + ['--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute Vala compiler "%s"' % ' '.join(exelist))
        (out, _) = p.communicate()
        out = out.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, out)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if 'Vala' in out:
            return ValaCompiler(exelist, version)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_rust_compiler(self):
        exelist = ['rustc']
        try:
            p = subprocess.Popen(exelist + ['--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute Rust compiler "%s"' % ' '.join(exelist))
        (out, _) = p.communicate()
        out = out.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, out)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if 'rustc' in out:
            return RustCompiler(exelist, version)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_swift_compiler(self):
        exelist = ['swiftc']
        try:
            p = subprocess.Popen(exelist + ['-v'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute Swift compiler "%s"' % ' '.join(exelist))
        (_, err) = p.communicate()
        err = err.decode(errors='ignore')
        vmatch = re.search(Environment.version_regex, err)
        if vmatch:
            version = vmatch.group(0)
        else:
            version = 'unknown version'
        if 'Swift' in err:
            return SwiftCompiler(exelist, version)
        raise EnvironmentException('Unknown compiler "' + ' '.join(exelist) + '"')

    def detect_static_linker(self, compiler):
        if compiler.is_cross:
            linker = self.cross_info.config['binaries']['ar']
        else:
            evar = 'AR'
            if evar in os.environ:
                linker = os.environ[evar].strip()
            elif isinstance(compiler, VisualStudioCCompiler):
                linker= self.vs_static_linker
            else:
                linker = self.default_static_linker
        basename = os.path.basename(linker).lower()
        if basename == 'lib' or basename == 'lib.exe':
            arg = '/?'
        else:
            arg = '--version'
        try:
            p = subprocess.Popen([linker, arg], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            raise EnvironmentException('Could not execute static linker "%s".' % linker)
        (out, err) = p.communicate()
        out = out.decode(errors='ignore')
        err = err.decode(errors='ignore')
        if '/OUT:' in out or '/OUT:' in err:
            return VisualStudioLinker([linker])
        if p.returncode == 0:
            return ArLinker([linker])
        if p.returncode == 1 and err.startswith('usage'): # OSX
            return ArLinker([linker])
        raise EnvironmentException('Unknown static linker "%s"' % linker)

    def detect_ccache(self):
        try:
            has_ccache = subprocess.call(['ccache', '--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        except OSError:
            has_ccache = 1
        if has_ccache == 0:
            cmdlist = ['ccache']
        else:
            cmdlist = []
        return cmdlist

    def get_objc_compiler_exelist(self):
        ccachelist = self.detect_ccache()
        evar = 'OBJCC'
        if evar in os.environ:
            return os.environ[evar].split()
        return ccachelist + self.default_objc

    def get_objcpp_compiler_exelist(self):
        ccachelist = self.detect_ccache()
        evar = 'OBJCXX'
        if evar in os.environ:
            return os.environ[evar].split()
        return ccachelist + self.default_objcpp

    def get_source_dir(self):
        return self.source_dir

    def get_build_dir(self):
        return self.build_dir

    def get_exe_suffix(self):
        return self.exe_suffix

    def get_import_lib_dir(self):
        "Install dir for the import library (library used for linking)"
        return self.get_libdir()

    def get_shared_lib_dir(self):
        "Install dir for the shared library"
        if self.win_libdir_layout:
            return self.get_bindir()
        return self.get_libdir()

    def get_static_lib_dir(self):
        "Install dir for the static library"
        return self.get_libdir()

    def get_object_suffix(self):
        return self.object_suffix

    def get_prefix(self):
        return self.coredata.get_builtin_option('prefix')

    def get_libdir(self):
        return self.coredata.get_builtin_option('libdir')

    def get_libexecdir(self):
        return self.coredata.get_builtin_option('libexecdir')

    def get_bindir(self):
        return self.coredata.get_builtin_option('bindir')

    def get_includedir(self):
        return self.coredata.get_builtin_option('includedir')

    def get_mandir(self):
        return self.coredata.get_builtin_option('mandir')

    def get_datadir(self):
        return self.coredata.get_builtin_option('datadir')


def get_args_from_envvars(lang):
    if lang == 'c':
        compile_args = os.environ.get('CFLAGS', '').split()
        link_args = compile_args + os.environ.get('LDFLAGS', '').split()
        compile_args += os.environ.get('CPPFLAGS', '').split()
    elif lang == 'cpp':
        compile_args = os.environ.get('CXXFLAGS', '').split()
        link_args = compile_args + os.environ.get('LDFLAGS', '').split()
        compile_args += os.environ.get('CPPFLAGS', '').split()
    elif lang == 'objc':
        compile_args = os.environ.get('OBJCFLAGS', '').split()
        link_args = compile_args + os.environ.get('LDFLAGS', '').split()
        compile_args += os.environ.get('CPPFLAGS', '').split()
    elif lang == 'objcpp':
        compile_args = os.environ.get('OBJCXXFLAGS', '').split()
        link_args = compile_args + os.environ.get('LDFLAGS', '').split()
        compile_args += os.environ.get('CPPFLAGS', '').split()
    elif lang == 'fortran':
        compile_args = os.environ.get('FFLAGS', '').split()
        link_args = compile_args + os.environ.get('LDFLAGS', '').split()
    else:
        compile_args = []
        link_args = []
    return (compile_args, link_args)

class CrossBuildInfo():
    def __init__(self, filename):
        self.config = {'properties': {}}
        self.parse_datafile(filename)
        if 'target_machine' in self.config:
            return
        if not 'host_machine' in self.config:
            raise mesonlib.MesonException('Cross info file must have either host or a target machine.')
        if not 'binaries' in self.config:
            raise mesonlib.MesonException('Cross file is missing "binaries".')

    def ok_type(self, i):
        return isinstance(i, str) or isinstance(i, int) or isinstance(i, bool)

    def parse_datafile(self, filename):
        config = configparser.ConfigParser()
        config.read(filename)
        # This is a bit hackish at the moment.
        for s in config.sections():
            self.config[s] = {}
            for entry in config[s]:
                value = config[s][entry]
                if ' ' in entry or '\t' in entry or "'" in entry or '"' in entry:
                    raise EnvironmentException('Malformed variable name %s in cross file..' % varname)
                try:
                    res = eval(value, {'true' : True, 'false' : False})
                except Exception:
                    raise EnvironmentException('Malformed value in cross file variable %s.' % varname)
                if self.ok_type(res):
                    self.config[s][entry] = res
                elif isinstance(res, list):
                    for i in res:
                        if not self.ok_type(i):
                            raise EnvironmentException('Malformed value in cross file variable %s.' % varname)
                    self.config[s][entry] = res
                else:
                    raise EnvironmentException('Malformed value in cross file variable %s.' % varname)

    def has_host(self):
        return 'host_machine' in self.config

    def has_target(self):
        return 'target_machine' in self.config

    def has_stdlib(self, language):
        return language + '_stdlib' in self.config['properties']

    def get_stdlib(self, language):
        return self.config['properties'][language + '_stdlib']

    def get_properties(self):
        return self.config['properties']

    # Wehn compiling a cross compiler we use the native compiler for everything.
    # But not when cross compiling a cross compiler.
    def need_cross_compiler(self):
        return 'host_machine' in self.config

    def need_exe_wrapper(self):
        if self.has_host() and detect_cpu_family() == 'x86_64' and \
           self.config['host_machine']['cpu_family'] == 'x86' and \
           self.config['host_machine']['system'] == detect_system():
            # Can almost always run 32-bit binaries on 64-bit natively if the
            # host and build systems are the same
            return False
        return True