aboutsummaryrefslogtreecommitdiffstats
path: root/erts/aclocal.m4
blob: e7b154a82b3bdce23271e8ff71345a8cb65e60df (plain) (blame)
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
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
dnl
dnl %CopyrightBegin%
dnl
dnl Copyright Ericsson AB 1998-2010. All Rights Reserved.
dnl
dnl The contents of this file are subject to the Erlang Public License,
dnl Version 1.1, (the "License"); you may not use this file except in
dnl compliance with the License. You should have received a copy of the
dnl Erlang Public License along with this software. If not, it can be
dnl retrieved online at http://www.erlang.org/.
dnl
dnl Software distributed under the License is distributed on an "AS IS"
dnl basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
dnl the License for the specific language governing rights and limitations
dnl under the License.
dnl
dnl %CopyrightEnd%
dnl

dnl
dnl aclocal.m4
dnl
dnl Local macros used in configure.in. The Local Macros which
dnl could/should be part of autoconf are prefixed LM_, macros specific
dnl to the Erlang system are prefixed ERL_.
dnl

AC_DEFUN(LM_PRECIOUS_VARS,
[

dnl ERL_TOP
AC_ARG_VAR(ERL_TOP, [Erlang/OTP top source directory])

dnl Tools
AC_ARG_VAR(CC, [C compiler])
AC_ARG_VAR(CFLAGS, [C compiler flags])
AC_ARG_VAR(STATIC_CFLAGS, [C compiler static flags])
AC_ARG_VAR(CFLAG_RUNTIME_LIBRARY_PATH, [runtime library path linker flag passed via C compiler])
AC_ARG_VAR(CPP, [C/C++ preprocessor])
AC_ARG_VAR(CPPFLAGS, [C/C++ preprocessor flags])
AC_ARG_VAR(CXX, [C++ compiler])
AC_ARG_VAR(CXXFLAGS, [C++ compiler flags])
AC_ARG_VAR(LD, [linker (is often overridden by configure)])
AC_ARG_VAR(LDFLAGS, [linker flags (can be risky to set since LD may be overriden by configure)])
AC_ARG_VAR(LIBS, [libraries])
AC_ARG_VAR(DED_LD, [linker for Dynamic Erlang Drivers (set all DED_LD* variables or none)])
AC_ARG_VAR(DED_LDFLAGS, [linker flags for Dynamic Erlang Drivers (set all DED_LD* variables or none)])
AC_ARG_VAR(DED_LD_FLAG_RUNTIME_LIBRARY_PATH, [runtime library path linker flag for Dynamic Erlang Drivers (set all DED_LD* variables or none)])
AC_ARG_VAR(LFS_CFLAGS, [large file support C compiler flags (set all LFS_* variables or none)])
AC_ARG_VAR(LFS_LDFLAGS, [large file support linker flags (set all LFS_* variables or none)])
AC_ARG_VAR(LFS_LIBS, [large file support libraries (set all LFS_* variables or none)])
AC_ARG_VAR(RANLIB, [ranlib])
AC_ARG_VAR(AR, [ar])
AC_ARG_VAR(GETCONF, [getconf])

dnl Cross system root
AC_ARG_VAR(erl_xcomp_sysroot, [Absolute cross system root path (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_isysroot, [Absolute cross system root include path (only used when cross compiling)])

dnl Cross compilation variables
AC_ARG_VAR(erl_xcomp_bigendian, [big endian system: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_linux_clock_gettime_correction, [clock_gettime() can be used for time correction: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_linux_nptl, [have Native POSIX Thread Library: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_linux_usable_sigusrx, [SIGUSR1 and SIGUSR2 can be used: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_linux_usable_sigaltstack, [have working sigaltstack(): yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_poll, [have working poll(): yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_kqueue, [have working kqueue(): yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_putenv_copy, [putenv() stores key-value copy: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_reliable_fpe, [have reliable floating point exceptions: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_getaddrinfo, [have working getaddrinfo() for both IPv4 and IPv6: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_gethrvtime_procfs_ioctl, [have working gethrvtime() which can be used with procfs ioctl(): yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_clock_gettime_cpu_time, [clock_gettime() can be used for retrieving process CPU time: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_after_morecore_hook, [__after_morecore_hook can track malloc()s core memory usage: yes|no (only used when cross compiling)])
AC_ARG_VAR(erl_xcomp_dlsym_brk_wrappers, [dlsym(RTLD_NEXT, _) brk wrappers can track malloc()s core memory usage: yes|no (only used when cross compiling)])

])

AC_DEFUN(ERL_XCOMP_SYSROOT_INIT,
[
erl_xcomp_without_sysroot=no
if test "$cross_compiling" = "yes"; then
    test "$erl_xcomp_sysroot" != "" || erl_xcomp_without_sysroot=yes
    test "$erl_xcomp_isysroot" != "" || erl_xcomp_isysroot="$erl_xcomp_sysroot"
else
    erl_xcomp_sysroot=
    erl_xcomp_isysroot=
fi
])

AC_DEFUN(LM_CHECK_GETCONF,
[
if test "$cross_compiling" != "yes"; then
    AC_CHECK_PROG([GETCONF], [getconf], [getconf], [false])
else
    dnl First check if we got a `<HOST>-getconf' in $PATH
    host_getconf="$host_alias-getconf"
    AC_CHECK_PROG([GETCONF], [$host_getconf], [$host_getconf], [false])
    if test "$GETCONF" = "false" && test "$erl_xcomp_sysroot" != ""; then
	dnl We should perhaps give up if we have'nt found it by now, but at
	dnl least in one Tilera MDE `getconf' under sysroot is a bourne
	dnl shell script which we can use. We try to find `<HOST>-getconf'
    	dnl or `getconf' under sysconf, but only under sysconf since
	dnl `getconf' in $PATH is almost guaranteed to be for the build
	dnl machine.
	GETCONF=
	prfx="$erl_xcomp_sysroot"
        AC_PATH_TOOL([GETCONF], [getconf], [false],
	             ["$prfx/usr/bin:$prfx/bin:$prfx/usr/local/bin"])
    fi
fi
])

dnl ----------------------------------------------------------------------
dnl
dnl LM_FIND_EMU_CC
dnl
dnl
dnl Tries fairly hard to find a C compiler that can handle jump tables.
dnl Defines the @EMU_CC@ variable for the makefiles and 
dnl inserts NO_JUMP_TABLE in the header if one cannot be found...
dnl

AC_DEFUN(LM_FIND_EMU_CC,
	[AC_CACHE_CHECK(for a compiler that handles jumptables,
			ac_cv_prog_emu_cc,
			[
AC_TRY_COMPILE([],[
    __label__ lbl1;
    __label__ lbl2;
    int x = magic();
    static void *jtab[2];

    jtab[0] = &&lbl1;
    jtab[1] = &&lbl2;
    goto *jtab[x];
lbl1:
    return 1;
lbl2:
    return 2;
],ac_cv_prog_emu_cc=$CC,ac_cv_prog_emu_cc=no)

if test $ac_cv_prog_emu_cc = no; then
	for ac_progname in emu_cc.sh gcc; do
  		IFS="${IFS= 	}"; ac_save_ifs="$IFS"; IFS=":"
  		ac_dummy="$PATH"
  		for ac_dir in $ac_dummy; do
    			test -z "$ac_dir" && ac_dir=.
    			if test -f $ac_dir/$ac_progname; then
      				ac_cv_prog_emu_cc=$ac_dir/$ac_progname
      				break
    			fi
  		done
  		IFS="$ac_save_ifs"
		if test $ac_cv_prog_emu_cc != no; then
			break
		fi
	done
fi

if test $ac_cv_prog_emu_cc != no; then
	save_CC=$CC
	save_CFLAGS=$CFLAGS
	save_CPPFLAGS=$CPPFLAGS
	CC=$ac_cv_prog_emu_cc
	CFLAGS=""
	CPPFLAGS=""
	AC_TRY_COMPILE([],[
    	__label__ lbl1;
    	__label__ lbl2;
    	int x = magic();
    	static void *jtab[2];

    	jtab[0] = &&lbl1;
    	jtab[1] = &&lbl2;
    	goto *jtab[x];
	lbl1:
    	return 1;
	lbl2:
    	return 2;
	],ac_cv_prog_emu_cc=$CC,ac_cv_prog_emu_cc=no)
	CC=$save_CC
	CFLAGS=$save_CFLAGS
	CPPFLAGS=$save_CPPFLAGS
fi
])
if test $ac_cv_prog_emu_cc = no; then
	AC_DEFINE(NO_JUMP_TABLE,[],[Defined if no found C compiler can handle jump tables])
	EMU_CC=$CC
else
	EMU_CC=$ac_cv_prog_emu_cc
fi
AC_SUBST(EMU_CC)
])		
			


dnl ----------------------------------------------------------------------
dnl
dnl LM_PROG_INSTALL_DIR
dnl
dnl This macro may be used by any OTP application.
dnl
dnl Figure out how to create directories with parents.
dnl (In my opinion INSTALL_DIR is a bad name, MKSUBDIRS or something is better)
dnl
dnl We prefer 'install -d', but use 'mkdir -p' if it exists.
dnl If none of these methods works, we give up.
dnl


AC_DEFUN(LM_PROG_INSTALL_DIR,
[AC_CACHE_CHECK(how to create a directory including parents,
ac_cv_prog_mkdir_p,
[
temp_name_base=config.$$
temp_name=$temp_name_base/x/y/z
$INSTALL -d $temp_name >/dev/null 2>&1
ac_cv_prog_mkdir_p=none
if test -d $temp_name; then
        ac_cv_prog_mkdir_p="$INSTALL -d"
else
        mkdir -p $temp_name >/dev/null 2>&1
        if test -d $temp_name; then
                ac_cv_prog_mkdir_p="mkdir -p"
        fi
fi
rm -fr $temp_name_base           
])

case "${ac_cv_prog_mkdir_p}" in
  none) AC_MSG_ERROR(don't know how create directories with parents) ;;
  *)    INSTALL_DIR="$ac_cv_prog_mkdir_p" AC_SUBST(INSTALL_DIR)     ;;
esac
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_PROG_PERL5
dnl
dnl Try to find perl version 5. If found set PERL to the absolute path
dnl of the program, if not found set PERL to false.
dnl
dnl On some systems /usr/bin/perl is perl 4 and e.g.
dnl /usr/local/bin/perl is perl 5. We try to handle this case by
dnl putting a couple of 
dnl Tries to handle the case that there are two programs called perl
dnl in the path and one of them is perl 5 and the other isn't. 
dnl
AC_DEFUN(LM_PROG_PERL5,
[AC_PATH_PROGS(PERL, perl5 perl, false,
   /usr/local/bin:/opt/local/bin:/usr/local/gnu/bin:${PATH})
changequote(, )dnl
dnl[ That bracket is needed to balance the right bracket below
if test "$PERL" = "false" || $PERL -e 'exit ($] >= 5)'; then
changequote([, ])dnl
  ac_cv_path_PERL=false
  PERL=false
dnl  AC_MSG_WARN(perl version 5 not found)
fi
])dnl


dnl ----------------------------------------------------------------------
dnl
dnl LM_DECL_SO_BSDCOMPAT
dnl
dnl Check if the system has the SO_BSDCOMPAT flag on sockets (linux) 
dnl
AC_DEFUN(LM_DECL_SO_BSDCOMPAT,
[AC_CACHE_CHECK([for SO_BSDCOMPAT declaration], ac_cv_decl_so_bsdcompat,
AC_TRY_COMPILE([#include <sys/socket.h>], [int i = SO_BSDCOMPAT;],
               ac_cv_decl_so_bsdcompat=yes,
               ac_cv_decl_so_bsdcompat=no))

case "${ac_cv_decl_so_bsdcompat}" in
  "yes" ) AC_DEFINE(HAVE_SO_BSDCOMPAT,[],
		[Define if you have SO_BSDCOMPAT flag on sockets]) ;;
  * ) ;;
esac
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_DECL_INADDR_LOOPBACK
dnl
dnl Try to find declaration of INADDR_LOOPBACK, if nowhere provide a default
dnl

AC_DEFUN(LM_DECL_INADDR_LOOPBACK,
[AC_CACHE_CHECK([for INADDR_LOOPBACK in netinet/in.h],
 ac_cv_decl_inaddr_loopback,
[AC_TRY_COMPILE([#include <sys/types.h>
#include <netinet/in.h>], [int i = INADDR_LOOPBACK;],
ac_cv_decl_inaddr_loopback=yes, ac_cv_decl_inaddr_loopback=no)
])

if test ${ac_cv_decl_inaddr_loopback} = no; then
  AC_CACHE_CHECK([for INADDR_LOOPBACK in rpc/types.h],
                   ac_cv_decl_inaddr_loopback_rpc,
                   AC_TRY_COMPILE([#include <rpc/types.h>],
                                   [int i = INADDR_LOOPBACK;],
                                   ac_cv_decl_inaddr_loopback_rpc=yes,
                                   ac_cv_decl_inaddr_loopback_rpc=no))

   case "${ac_cv_decl_inaddr_loopback_rpc}" in
     "yes" )
        AC_DEFINE(DEF_INADDR_LOOPBACK_IN_RPC_TYPES_H,[],
		[Define if you need to include rpc/types.h to get INADDR_LOOPBACK defined]) ;;
      * )
  	AC_CACHE_CHECK([for INADDR_LOOPBACK in winsock2.h],
                   ac_cv_decl_inaddr_loopback_winsock2,
                   AC_TRY_COMPILE([#define WIN32_LEAN_AND_MEAN
				   #include <winsock2.h>],
                                   [int i = INADDR_LOOPBACK;],
                                   ac_cv_decl_inaddr_loopback_winsock2=yes,
                                   ac_cv_decl_inaddr_loopback_winsock2=no))
	case "${ac_cv_decl_inaddr_loopback_winsock2}" in
     		"yes" )
			AC_DEFINE(DEF_INADDR_LOOPBACK_IN_WINSOCK2_H,[],
				[Define if you need to include winsock2.h to get INADDR_LOOPBACK defined]) ;;
		* )
			# couldn't find it anywhere
        		AC_DEFINE(HAVE_NO_INADDR_LOOPBACK,[],
				[Define if you don't have a definition of INADDR_LOOPBACK]) ;;
	esac;;
   esac
fi
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_STRUCT_SOCKADDR_SA_LEN
dnl
dnl Check if the sockaddr structure has the field sa_len
dnl

AC_DEFUN(LM_STRUCT_SOCKADDR_SA_LEN,
[AC_CACHE_CHECK([whether struct sockaddr has sa_len field],
                ac_cv_struct_sockaddr_sa_len,
AC_TRY_COMPILE([#include <sys/types.h>
#include <sys/socket.h>], [struct sockaddr s; s.sa_len = 10;],
  ac_cv_struct_sockaddr_sa_len=yes, ac_cv_struct_sockaddr_sa_len=no))

dnl FIXME convbreak
case ${ac_cv_struct_sockaddr_sa_len} in
  "no" ) AC_DEFINE(NO_SA_LEN,[1],[Define if you dont have salen]) ;;
  *) ;;
esac
])

dnl ----------------------------------------------------------------------
dnl
dnl LM_STRUCT_EXCEPTION
dnl
dnl Check to see whether the system supports the matherr function
dnl and its associated type "struct exception".
dnl

AC_DEFUN(LM_STRUCT_EXCEPTION,
[AC_CACHE_CHECK([for struct exception (and matherr function)],
 ac_cv_struct_exception,
AC_TRY_COMPILE([#include <math.h>],
  [struct exception x; x.type = DOMAIN; x.type = SING;],
  ac_cv_struct_exception=yes, ac_cv_struct_exception=no))

case "${ac_cv_struct_exception}" in
  "yes" ) AC_DEFINE(USE_MATHERR,[1],[Define if you have matherr() function and struct exception type]) ;;
  *  ) ;;
esac
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_SYS_IPV6
dnl
dnl Check for ipv6 support and what the in6_addr structure is called.
dnl (early linux used in_addr6 insted of in6_addr)
dnl

AC_DEFUN(LM_SYS_IPV6,
[AC_MSG_CHECKING(for IP version 6 support)
AC_CACHE_VAL(ac_cv_sys_ipv6_support,
[ok_so_far=yes
 AC_TRY_COMPILE([#include <sys/types.h>
#include <netinet/in.h>],
   [struct in6_addr a6; struct sockaddr_in6 s6;], ok_so_far=yes, ok_so_far=no)

if test $ok_so_far = yes; then
  ac_cv_sys_ipv6_support=yes
else
  AC_TRY_COMPILE([#include <sys/types.h>
#include <netinet/in.h>],
    [struct in_addr6 a6; struct sockaddr_in6 s6;],
    ac_cv_sys_ipv6_support=in_addr6, ac_cv_sys_ipv6_support=no)
fi
])dnl

dnl
dnl Have to use old style AC_DEFINE due to BC with old autoconf.
dnl

case ${ac_cv_sys_ipv6_support} in
  yes)
    AC_MSG_RESULT(yes)
    AC_DEFINE(HAVE_IN6,[1],[Define if ipv6 is present])
    ;;
  in_addr6)
    AC_MSG_RESULT([yes (but I am redefining in_addr6 to in6_addr)])
    AC_DEFINE(HAVE_IN6,[1],[Define if ipv6 is present])
    AC_DEFINE(HAVE_IN_ADDR6_STRUCT,[],[Early linux used in_addr6 instead of in6_addr, define if you have this])
    ;;
  *)
    AC_MSG_RESULT(no)
    ;;
esac
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_SYS_MULTICAST
dnl
dnl Check for multicast support. Only checks for multicast options in
dnl setsockopt(), no check is performed that multicasting actually works.
dnl If options are found defines HAVE_MULTICAST_SUPPORT
dnl

AC_DEFUN(LM_SYS_MULTICAST,
[AC_CACHE_CHECK([for multicast support], ac_cv_sys_multicast_support,
[AC_EGREP_CPP(yes,
[#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#if defined(IP_MULTICAST_TTL) && defined(IP_MULTICAST_LOOP) && defined(IP_MULTICAST_IF) && defined(IP_ADD_MEMBERSHIP) && defined(IP_DROP_MEMBERSHIP)
yes
#endif
], ac_cv_sys_multicast_support=yes, ac_cv_sys_multicast_support=no)])
if test $ac_cv_sys_multicast_support = yes; then
  AC_DEFINE(HAVE_MULTICAST_SUPPORT,[1],
	[Define if setsockopt() accepts multicast options])
fi
])dnl


dnl ----------------------------------------------------------------------
dnl
dnl LM_DECL_SYS_ERRLIST
dnl
dnl Define SYS_ERRLIST_DECLARED if the variable sys_errlist is declared
dnl in a system header file, stdio.h or errno.h.
dnl

AC_DEFUN(LM_DECL_SYS_ERRLIST,
[AC_CACHE_CHECK([for sys_errlist declaration in stdio.h or errno.h],
  ac_cv_decl_sys_errlist,
[AC_TRY_COMPILE([#include <stdio.h>
#include <errno.h>], [char *msg = *(sys_errlist + 1);],
  ac_cv_decl_sys_errlist=yes, ac_cv_decl_sys_errlist=no)])
if test $ac_cv_decl_sys_errlist = yes; then
  AC_DEFINE(SYS_ERRLIST_DECLARED,[],
	[define if the variable sys_errlist is declared in a system header file])
fi
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_CHECK_FUNC_DECL( funname, declaration [, extra includes 
dnl                     [, action-if-found [, action-if-not-found]]] )
dnl
dnl Checks if the declaration "declaration" of "funname" conflicts
dnl with the header files idea of how the function should be
dnl declared. It is useful on systems which lack prototypes and you
dnl need to provide your own (e.g. when you want to take the address
dnl of a function). The 4'th argument is expanded if conflicting, 
dnl the 5'th argument otherwise
dnl
dnl

AC_DEFUN(LM_CHECK_FUNC_DECL,
[AC_MSG_CHECKING([for conflicting declaration of $1])
AC_CACHE_VAL(ac_cv_func_decl_$1,
[AC_TRY_COMPILE([#include <stdio.h>
$3],[$2
char *c = (char *)$1;
], eval "ac_cv_func_decl_$1=no", eval "ac_cv_func_decl_$1=yes")])
if eval "test \"`echo '$ac_cv_func_decl_'$1`\" = yes"; then
  AC_MSG_RESULT(yes)
  ifelse([$4], , :, [$4])
else
  AC_MSG_RESULT(no)
ifelse([$5], , , [$5
])dnl
fi
])


dnl ----------------------------------------------------------------------
dnl
dnl LM_CHECK_THR_LIB
dnl
dnl This macro may be used by any OTP application.
dnl
dnl LM_CHECK_THR_LIB sets THR_LIBS, THR_DEFS, and THR_LIB_NAME. It also
dnl checks for some pthread headers which will appear in DEFS or config.h.
dnl

AC_DEFUN(LM_CHECK_THR_LIB,
[

NEED_NPTL_PTHREAD_H=no

dnl win32?
AC_MSG_CHECKING([for native win32 threads])
if test "X$host_os" = "Xwin32"; then
    AC_MSG_RESULT(yes)
    THR_DEFS="-DWIN32_THREADS"
    THR_LIBS=
    THR_LIB_NAME=win32_threads
    THR_LIB_TYPE=win32_threads
else
    AC_MSG_RESULT(no)
    THR_DEFS=
    THR_LIBS=
    THR_LIB_NAME=
    THR_LIB_TYPE=posix_unknown

dnl Try to find POSIX threads

dnl The usual pthread lib...
    AC_CHECK_LIB(pthread, pthread_create, THR_LIBS="-lpthread")

dnl FreeBSD has pthreads in special c library, c_r...
    if test "x$THR_LIBS" = "x"; then
	AC_CHECK_LIB(c_r, pthread_create, THR_LIBS="-lc_r")
    fi

dnl On ofs1 the '-pthread' switch should be used
    if test "x$THR_LIBS" = "x"; then
	AC_MSG_CHECKING([if the '-pthread' switch can be used])
	saved_cflags=$CFLAGS
	CFLAGS="$CFLAGS -pthread"
	AC_TRY_LINK([#include <pthread.h>],
		    pthread_create((void*)0,(void*)0,(void*)0,(void*)0);,
		    [THR_DEFS="-pthread"
		     THR_LIBS="-pthread"])
	CFLAGS=$saved_cflags
	if test "x$THR_LIBS" != "x"; then
	    AC_MSG_RESULT(yes)
	else
	    AC_MSG_RESULT(no)
	fi
    fi

    if test "x$THR_LIBS" != "x"; then
	THR_DEFS="$THR_DEFS -D_THREAD_SAFE -D_REENTRANT -DPOSIX_THREADS"
	THR_LIB_NAME=pthread
	case $host_os in
	    solaris*)
		THR_DEFS="$THR_DEFS -D_POSIX_PTHREAD_SEMANTICS" ;;
	    linux*)
		THR_DEFS="$THR_DEFS -D_POSIX_THREAD_SAFE_FUNCTIONS"

		LM_CHECK_GETCONF
		AC_MSG_CHECKING(for Native POSIX Thread Library)
		libpthr_vsn=`$GETCONF GNU_LIBPTHREAD_VERSION 2>/dev/null`
		if test $? -eq 0; then
		    case "$libpthr_vsn" in
			*nptl*|*NPTL*) nptl=yes;;
			*) nptl=no;;
		    esac
		elif test "$cross_compiling" = "yes"; then
		    case "$erl_xcomp_linux_nptl" in
			"") nptl=cross;;
			yes|no) nptl=$erl_xcomp_linux_nptl;;
			*) AC_MSG_ERROR([Bad erl_xcomp_linux_nptl value: $erl_xcomp_linux_nptl]);;
		    esac
		else
		    nptl=no
		fi
		AC_MSG_RESULT($nptl)
		if test $nptl = cross; then
		    nptl=yes
		    AC_MSG_WARN([result yes guessed because of cross compilation])
		fi
		if test $nptl = yes; then
		    THR_LIB_TYPE=posix_nptl
		    need_nptl_incldir=no
		    AC_CHECK_HEADER(nptl/pthread.h,
				    [need_nptl_incldir=yes
				     NEED_NPTL_PTHREAD_H=yes])
		    if test $need_nptl_incldir = yes; then
			# Ahh...
			nptl_path="$C_INCLUDE_PATH:$CPATH"
			if test X$cross_compiling != Xyes; then
			    nptl_path="$nptl_path:/usr/local/include:/usr/include"
			else
			    IROOT="$erl_xcomp_isysroot"
			    test "$IROOT" != "" || IROOT="$erl_xcomp_sysroot"
			    test "$IROOT" != "" || AC_MSG_ERROR([Don't know where to search for includes! Please set erl_xcomp_isysroot])
			    nptl_path="$nptl_path:$IROOT/usr/local/include:$IROOT/usr/include"
			fi
			nptl_ws_path=
			save_ifs="$IFS"; IFS=":"
			for dir in $nptl_path; do
			    if test "x$dir" != "x"; then
				nptl_ws_path="$nptl_ws_path $dir"
			    fi
			done
			IFS=$save_ifs
			nptl_incldir=
			for dir in $nptl_ws_path; do
		            AC_CHECK_HEADER($dir/nptl/pthread.h,
					    nptl_incldir=$dir/nptl)
			    if test "x$nptl_incldir" != "x"; then
				THR_DEFS="$THR_DEFS -isystem $nptl_incldir"
				break
			    fi
			done
			if test "x$nptl_incldir" = "x"; then
			    AC_MSG_ERROR(Failed to locate nptl system include directory)
			fi
		    fi
		fi
		;;
	    *) ;;
	esac

	dnl We sometimes need THR_DEFS in order to find certain headers
	dnl (at least for pthread.h on osf1).
	saved_cppflags=$CPPFLAGS
	CPPFLAGS="$CPPFLAGS $THR_DEFS"

	dnl
	dnl Check for headers
	dnl

	AC_CHECK_HEADER(pthread.h,
			AC_DEFINE(HAVE_PTHREAD_H, 1, \
[Define if you have the <pthread.h> header file.]))

	dnl Some Linuxes have <pthread/mit/pthread.h> instead of <pthread.h>
	AC_CHECK_HEADER(pthread/mit/pthread.h, \
			AC_DEFINE(HAVE_MIT_PTHREAD_H, 1, \
[Define if the pthread.h header file is in pthread/mit directory.]))

	dnl restore CPPFLAGS
	CPPFLAGS=$saved_cppflags

    fi
fi

])

AC_DEFUN(ERL_INTERNAL_LIBS,
[

ERTS_INTERNAL_X_LIBS=

AC_CHECK_LIB(kstat, kstat_open,
[AC_DEFINE(HAVE_KSTAT, 1, [Define if you have kstat])
ERTS_INTERNAL_X_LIBS="$ERTS_INTERNAL_X_LIBS -lkstat"])

AC_SUBST(ERTS_INTERNAL_X_LIBS)

])

dnl ----------------------------------------------------------------------
dnl
dnl ERL_FIND_ETHR_LIB
dnl
dnl NOTE! This macro may be changed at any time! Should *only* be used by
dnl       ERTS!
dnl
dnl Find a thread library to use. Sets ETHR_LIBS to libraries to link
dnl with, ETHR_X_LIBS to extra libraries to link with (same as ETHR_LIBS
dnl except that the ethread lib itself is not included), ETHR_DEFS to
dnl defines to compile with, ETHR_THR_LIB_BASE to the name of the
dnl thread library which the ethread library is based on, and ETHR_LIB_NAME
dnl to the name of the library where the ethread implementation is located.
dnl  ERL_FIND_ETHR_LIB currently searches for 'pthreads', and
dnl 'win32_threads'. If no thread library was found ETHR_LIBS, ETHR_X_LIBS,
dnl ETHR_DEFS, ETHR_THR_LIB_BASE, and ETHR_LIB_NAME are all set to the
dnl empty string.
dnl

AC_DEFUN(ERL_FIND_ETHR_LIB,
[

LM_CHECK_THR_LIB
ERL_INTERNAL_LIBS

ethr_have_native_atomics=no
ethr_have_native_spinlock=no
ETHR_THR_LIB_BASE="$THR_LIB_NAME"
ETHR_THR_LIB_BASE_TYPE="$THR_LIB_TYPE"
ETHR_DEFS="$THR_DEFS"
ETHR_X_LIBS="$THR_LIBS $ERTS_INTERNAL_X_LIBS"
ETHR_LIBS=
ETHR_LIB_NAME=

ethr_modified_default_stack_size=

dnl Name of lib where ethread implementation is located
ethr_lib_name=ethread

case "$THR_LIB_NAME" in

    win32_threads)
	ETHR_THR_LIB_BASE_DIR=win
	# * _WIN32_WINNT >= 0x0400 is needed for
	#   TryEnterCriticalSection
	# * _WIN32_WINNT >= 0x0403 is needed for
	#   InitializeCriticalSectionAndSpinCount
	# The ethread lib will refuse to build if _WIN32_WINNT < 0x0403.
	#
	# -D_WIN32_WINNT should have been defined in $CPPFLAGS; fetch it
	# and save it in ETHR_DEFS.
	found_win32_winnt=no
	for cppflag in $CPPFLAGS; do
	    case $cppflag in
		-DWINVER*)
		    ETHR_DEFS="$ETHR_DEFS $cppflag"
		    ;;
		-D_WIN32_WINNT*)
		    ETHR_DEFS="$ETHR_DEFS $cppflag"
		    found_win32_winnt=yes
		    ;;
		*)
		    ;;
	    esac
        done
        if test $found_win32_winnt = no; then
	    AC_MSG_ERROR([-D_WIN32_WINNT missing in CPPFLAGS])
        fi
	ethr_have_native_atomics=yes
	ethr_have_native_spinlock=yes
	AC_DEFINE(ETHR_WIN32_THREADS, 1, [Define if you have win32 threads])
	;;

    pthread)
	ETHR_THR_LIB_BASE_DIR=pthread
    	AC_DEFINE(ETHR_PTHREADS, 1, [Define if you have pthreads])
	case $host_os in
	    openbsd*)
		# The default stack size is insufficient for our needs
		# on OpenBSD. We increase it to 256 kilo words.
		ethr_modified_default_stack_size=256;;
	    linux*)
		ETHR_DEFS="$ETHR_DEFS -D_GNU_SOURCE"

		if test	X$cross_compiling = Xyes; then
		    case X$erl_xcomp_linux_usable_sigusrx in
			X) usable_sigusrx=cross;;
			Xyes|Xno) usable_sigusrx=$erl_xcomp_linux_usable_sigusrx;;
			*) AC_MSG_ERROR([Bad erl_xcomp_linux_usable_sigusrx value: $erl_xcomp_linux_usable_sigusrx]);;
		    esac
		    case X$erl_xcomp_linux_usable_sigaltstack in
			X) usable_sigaltstack=cross;;
			Xyes|Xno) usable_sigaltstack=$erl_xcomp_linux_usable_sigaltstack;;
			*) AC_MSG_ERROR([Bad erl_xcomp_linux_usable_sigaltstack value: $erl_xcomp_linux_usable_sigaltstack]);;
		    esac
		else
		    # FIXME: Test for actual problems instead of kernel versions
		    linux_kernel_vsn_=`uname -r`
		    case $linux_kernel_vsn_ in
			[[0-1]].*|2.[[0-1]]|2.[[0-1]].*)
			    usable_sigusrx=no
			    usable_sigaltstack=no;;
			2.[[2-3]]|2.[[2-3]].*)
			    usable_sigusrx=yes
			    usable_sigaltstack=no;;
		    	*)
			    usable_sigusrx=yes
			    usable_sigaltstack=yes;;
		    esac
		fi

		AC_MSG_CHECKING(if SIGUSR1 and SIGUSR2 can be used)
		AC_MSG_RESULT($usable_sigusrx)
		if test $usable_sigusrx = cross; then
		    usable_sigusrx=yes
		    AC_MSG_WARN([result yes guessed because of cross compilation])
		fi
		if test $usable_sigusrx = no; then
		    ETHR_DEFS="$ETHR_DEFS -DETHR_UNUSABLE_SIGUSRX"
		fi

		AC_MSG_CHECKING(if sigaltstack can be used)
		AC_MSG_RESULT($usable_sigaltstack)
		if test $usable_sigaltstack = cross; then
		    usable_sigaltstack=yes
		    AC_MSG_WARN([result yes guessed because of cross compilation])
		fi
		if test $usable_sigaltstack = no; then
		    ETHR_DEFS="$ETHR_DEFS -DETHR_UNUSABLE_SIGALTSTACK"
		fi
		;;
	    *) ;;
	esac

	dnl We sometimes need ETHR_DEFS in order to find certain headers
	dnl (at least for pthread.h on osf1).
	saved_cppflags="$CPPFLAGS"
	CPPFLAGS="$CPPFLAGS $ETHR_DEFS"

	dnl We need the thread library in order to find some functions
	saved_libs="$LIBS"
	LIBS="$LIBS $ETHR_X_LIBS"

	dnl
	dnl Check for headers
	dnl

	AC_CHECK_HEADER(pthread.h, \
			AC_DEFINE(ETHR_HAVE_PTHREAD_H, 1, \
[Define if you have the <pthread.h> header file.]))

	dnl Some Linuxes have <pthread/mit/pthread.h> instead of <pthread.h>
	AC_CHECK_HEADER(pthread/mit/pthread.h, \
			AC_DEFINE(ETHR_HAVE_MIT_PTHREAD_H, 1, \
[Define if the pthread.h header file is in pthread/mit directory.]))

	if test $NEED_NPTL_PTHREAD_H = yes; then
	    AC_DEFINE(ETHR_NEED_NPTL_PTHREAD_H, 1, \
[Define if you need the <nptl/pthread.h> header file.])
	fi

	AC_CHECK_HEADER(sched.h, \
			AC_DEFINE(ETHR_HAVE_SCHED_H, 1, \
[Define if you have the <sched.h> header file.]))

	AC_CHECK_HEADER(sys/time.h, \
			AC_DEFINE(ETHR_HAVE_SYS_TIME_H, 1, \
[Define if you have the <sys/time.h> header file.]))

	AC_TRY_COMPILE([#include <time.h>
			#include <sys/time.h>], 
			[struct timeval *tv; return 0;],
			AC_DEFINE(ETHR_TIME_WITH_SYS_TIME, 1, \
[Define if you can safely include both <sys/time.h> and <time.h>.]))


	dnl
	dnl Check for functions
	dnl

	AC_CHECK_FUNC(pthread_spin_lock, \
			[ethr_have_native_spinlock=yes \
			 AC_DEFINE(ETHR_HAVE_PTHREAD_SPIN_LOCK, 1, \
[Define if you have the pthread_spin_lock function.])])

	have_sched_yield=no
	have_librt_sched_yield=no
	AC_CHECK_FUNC(sched_yield, [have_sched_yield=yes])
	if test $have_sched_yield = no; then
	    AC_CHECK_LIB(rt, sched_yield,
			 [have_librt_sched_yield=yes
			  ETHR_X_LIBS="$ETHR_X_LIBS -lrt"])
	fi
	if test $have_sched_yield = yes || test $have_librt_sched_yield = yes; then
	    AC_DEFINE(ETHR_HAVE_SCHED_YIELD, 1, [Define if you have the sched_yield() function.])
	    AC_MSG_CHECKING([whether sched_yield() returns an int])
	    sched_yield_ret_int=no
	    AC_TRY_COMPILE([
				#ifdef ETHR_HAVE_SCHED_H
				#include <sched.h>
				#endif
			   ],
			   [int sched_yield();],
			   [sched_yield_ret_int=yes])
	    AC_MSG_RESULT([$sched_yield_ret_int])
	    if test $sched_yield_ret_int = yes; then
		AC_DEFINE(ETHR_SCHED_YIELD_RET_INT, 1, [Define if sched_yield() returns an int.])
	    fi
	fi

	have_pthread_yield=no
	AC_CHECK_FUNC(pthread_yield, [have_pthread_yield=yes])
	if test $have_pthread_yield = yes; then
	    AC_DEFINE(ETHR_HAVE_PTHREAD_YIELD, 1, [Define if you have the pthread_yield() function.])
	    AC_MSG_CHECKING([whether pthread_yield() returns an int])
	    pthread_yield_ret_int=no
	    AC_TRY_COMPILE([
				#if defined(ETHR_NEED_NPTL_PTHREAD_H)
				#include <nptl/pthread.h>
				#elif defined(ETHR_HAVE_MIT_PTHREAD_H)
				#include <pthread/mit/pthread.h>
				#elif defined(ETHR_HAVE_PTHREAD_H)
				#include <pthread.h>
				#endif
			   ],
			   [int pthread_yield();],
			   [pthread_yield_ret_int=yes])
	    AC_MSG_RESULT([$pthread_yield_ret_int])
	    if test $pthread_yield_ret_int = yes; then
		AC_DEFINE(ETHR_PTHREAD_YIELD_RET_INT, 1, [Define if pthread_yield() returns an int.])
	    fi
	fi

	have_pthread_rwlock_init=no
	AC_CHECK_FUNC(pthread_rwlock_init, [have_pthread_rwlock_init=yes])
	if test $have_pthread_rwlock_init = yes; then

	    ethr_have_pthread_rwlockattr_setkind_np=no
	    AC_CHECK_FUNC(pthread_rwlockattr_setkind_np,
			  [ethr_have_pthread_rwlockattr_setkind_np=yes])

	    if test $ethr_have_pthread_rwlockattr_setkind_np = yes; then
		AC_DEFINE(ETHR_HAVE_PTHREAD_RWLOCKATTR_SETKIND_NP, 1, \
[Define if you have the pthread_rwlockattr_setkind_np() function.])

		AC_MSG_CHECKING([for PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP])
		ethr_pthread_rwlock_writer_nonrecursive_initializer_np=no
		AC_TRY_LINK([
				#if defined(ETHR_NEED_NPTL_PTHREAD_H)
				#include <nptl/pthread.h>
				#elif defined(ETHR_HAVE_MIT_PTHREAD_H)
				#include <pthread/mit/pthread.h>
				#elif defined(ETHR_HAVE_PTHREAD_H)
				#include <pthread.h>
				#endif
			    ],
			    [
				pthread_rwlockattr_t *attr;
				return pthread_rwlockattr_setkind_np(attr,
				    PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP);
			    ],
			    [ethr_pthread_rwlock_writer_nonrecursive_initializer_np=yes])
		AC_MSG_RESULT([$ethr_pthread_rwlock_writer_nonrecursive_initializer_np])
		if test $ethr_pthread_rwlock_writer_nonrecursive_initializer_np = yes; then
		    AC_DEFINE(ETHR_HAVE_PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP, 1, \
[Define if you have the PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP rwlock attribute.])
		fi
	    fi
	fi

	if test "$force_pthread_rwlocks" = "yes"; then

	    AC_DEFINE(ETHR_FORCE_PTHREAD_RWLOCK, 1, \
[Define if you want to force usage of pthread rwlocks])

	    if test $have_pthread_rwlock_init = yes; then
		AC_MSG_WARN([Forced usage of pthread rwlocks. Note that this implementation may suffer from starvation issues.])
	    else
		AC_MSG_ERROR([User forced usage of pthread rwlock, but no such implementation was found])
	    fi
	fi

	AC_CHECK_FUNC(pthread_attr_setguardsize, \
			AC_DEFINE(ETHR_HAVE_PTHREAD_ATTR_SETGUARDSIZE, 1, \
[Define if you have the pthread_attr_setguardsize function.]))

	linux_futex=no
	AC_MSG_CHECKING([for Linux futexes])
	AC_TRY_LINK([
			#include <sys/syscall.h>
			#include <unistd.h>
			#include <linux/futex.h>
			#include <sys/time.h>
		    ],
		    [
			int i = 1;
			syscall(__NR_futex, (void *) &i, FUTEX_WAKE, 1,
				(void*)0,(void*)0, 0);
			syscall(__NR_futex, (void *) &i, FUTEX_WAIT, 0,
				(void*)0,(void*)0, 0);
			return 0;
		    ],
		    linux_futex=yes)
	AC_MSG_RESULT([$linux_futex])
	test $linux_futex = yes && AC_DEFINE(ETHR_HAVE_LINUX_FUTEX, 1, [Define if you have a linux futex implementation.])

	AC_MSG_CHECKING([for GCC atomic operations])
	ethr_have_gcc_atomic_ops=no
	AC_TRY_LINK([],
		    [
			long res;
			volatile long val;
			res = __sync_val_compare_and_swap(&val, (long) 1, (long) 0);
			res = __sync_add_and_fetch(&val, (long) 1);
			res = __sync_sub_and_fetch(&val, (long) 1);
			res = __sync_fetch_and_and(&val, (long) 1);
			res = __sync_fetch_and_or(&val, (long) 1);
		    ],
		    [ethr_have_native_atomics=yes
		     ethr_have_gcc_atomic_ops=yes])
	AC_MSG_RESULT([$ethr_have_gcc_atomic_ops])
	test $ethr_have_gcc_atomic_ops = yes && AC_DEFINE(ETHR_HAVE_GCC_ATOMIC_OPS, 1, [Define if you have gcc atomic operations])

	case "$host_cpu" in
	  sun4u | sparc64 | sun4v)
		ethr_have_native_atomics=yes;;
	  i86pc | i386 | i486 | i586 | i686 | x86_64 | amd64)
		ethr_have_native_atomics=yes;;
	  macppc | ppc | "Power Macintosh")
		ethr_have_native_atomics=yes;;
	  tile)
		ethr_have_native_atomics=yes;;
	  *)
		;;
	esac

	AC_MSG_CHECKING([for a usable libatomic_ops implementation])
	case "x$with_libatomic_ops" in
	    xno | xyes | x)
		libatomic_ops_include=
		;;
	    *)
		if test -d "${with_libatomic_ops}/include"; then
		    libatomic_ops_include="-I$with_libatomic_ops/include"
		    CPPFLAGS="$CPPFLAGS $libatomic_ops_include"
		else
		    AC_MSG_ERROR([libatomic_ops include directory $with_libatomic_ops/include not found])
		fi;;
	esac
	ethr_have_libatomic_ops=no
	AC_TRY_LINK([#include "atomic_ops.h"],
		    [
			volatile AO_t x;
			AO_t y;
			int z;

			AO_nop_full();
			AO_store(&x, (AO_t) 0);
			z = AO_load(&x);
			z = AO_compare_and_swap(&x, (AO_t) 0, (AO_t) 1);
		    ],
		    [ethr_have_native_atomics=yes
		     ethr_have_libatomic_ops=yes])
	AC_MSG_RESULT([$ethr_have_libatomic_ops])
	if test $ethr_have_libatomic_ops = yes; then
	    AC_CHECK_SIZEOF(AO_t, ,
			    [
				#include <stdio.h>
				#include "atomic_ops.h"
			    ])
	    AC_DEFINE_UNQUOTED(ETHR_SIZEOF_AO_T, $ac_cv_sizeof_AO_t, [Define to the size of AO_t if libatomic_ops is used])

	    AC_DEFINE(ETHR_HAVE_LIBATOMIC_OPS, 1, [Define if you have libatomic_ops atomic operations])
	    if test "x$with_libatomic_ops" != "xno" && test "x$with_libatomic_ops" != "x"; then
		AC_DEFINE(ETHR_PREFER_LIBATOMIC_OPS_NATIVE_IMPLS, 1, [Define if you prefer libatomic_ops native ethread implementations])
	    fi
	    ETHR_DEFS="$ETHR_DEFS $libatomic_ops_include"
	elif test "x$with_libatomic_ops" != "xno" && test "x$with_libatomic_ops" != "x"; then
	    AC_MSG_ERROR([No usable libatomic_ops implementation found])
	fi

	dnl Restore LIBS
	LIBS=$saved_libs
	dnl restore CPPFLAGS
	CPPFLAGS=$saved_cppflags

	;;
    *)
	;;
esac

AC_MSG_CHECKING([whether default stack size should be modified])
if test "x$ethr_modified_default_stack_size" != "x"; then
	AC_DEFINE_UNQUOTED(ETHR_MODIFIED_DEFAULT_STACK_SIZE, $ethr_modified_default_stack_size, [Define if you want to modify the default stack size])
	AC_MSG_RESULT([yes; to $ethr_modified_default_stack_size kilo words])
else
	AC_MSG_RESULT([no])
fi

if test "x$ETHR_THR_LIB_BASE" != "x"; then
	ETHR_DEFS="-DUSE_THREADS $ETHR_DEFS"
	ETHR_LIBS="-l$ethr_lib_name -lerts_internal_r $ETHR_X_LIBS"
	ETHR_LIB_NAME=$ethr_lib_name
fi

AC_CHECK_SIZEOF(void *)
AC_DEFINE_UNQUOTED(ETHR_SIZEOF_PTR, $ac_cv_sizeof_void_p, [Define to the size of pointers])

AC_ARG_ENABLE(native-ethr-impls,
	      AS_HELP_STRING([--disable-native-ethr-impls],
                             [disable native ethread implementations]),
[ case "$enableval" in
    no) disable_native_ethr_impls=yes ;;
    *)  disable_native_ethr_impls=no ;;
  esac ], disable_native_ethr_impls=no)

test "X$disable_native_ethr_impls" = "Xyes" &&
  AC_DEFINE(ETHR_DISABLE_NATIVE_IMPLS, 1, [Define if you want to disable native ethread implementations])

AC_ARG_ENABLE(prefer-gcc-native-ethr-impls,
	      AS_HELP_STRING([--enable-prefer-gcc-native-ethr-impls],
			     [prefer gcc native ethread implementations]),
[ case "$enableval" in
    yes) enable_prefer_gcc_native_ethr_impls=yes ;;
    *)  enable_prefer_gcc_native_ethr_impls=no ;;
  esac ], enable_prefer_gcc_native_ethr_impls=no)

test $enable_prefer_gcc_native_ethr_impls = yes &&
  AC_DEFINE(ETHR_PREFER_GCC_NATIVE_IMPLS, 1, [Define if you prefer gcc native ethread implementations])

AC_ARG_ENABLE(ethread-pre-pentium4-compatibility,
	      AS_HELP_STRING([--enable-ethread-pre-pentium4-compatibility],
			     [enable compatibility with x86 processors before pentium 4 (back to 486) in the ethread library]),
[ case "$enableval" in
    yes) enable_ethread_pre_pentium4_compatibility=yes ;;
    *)  enable_ethread_pre_pentium4_compatibilit=no ;;
  esac ], enable_ethread_pre_pentium4_compatibilit=no)

test $enable_ethread_pre_pentium4_compatibilit = yes &&
  AC_DEFINE(ETHR_PRE_PENTIUM4_COMPAT, 1, [Define if you want compatibilty with x86 processors before pentium4.])

AC_ARG_WITH(libatomic_ops,
	    AS_HELP_STRING([--with-libatomic_ops=PATH],
			   [specify and prefer usage of libatomic_ops in the ethread library]))

AC_DEFINE(ETHR_HAVE_ETHREAD_DEFINES, 1, \
[Define if you have all ethread defines])

AC_SUBST(ETHR_X_LIBS)
AC_SUBST(ETHR_LIBS)
AC_SUBST(ETHR_LIB_NAME)
AC_SUBST(ETHR_DEFS)
AC_SUBST(ETHR_THR_LIB_BASE)
AC_SUBST(ETHR_THR_LIB_BASE_DIR)

])



dnl ----------------------------------------------------------------------
dnl
dnl ERL_TIME_CORRECTION
dnl
dnl In the presence of a high resolution realtime timer Erlang can adapt
dnl its view of time relative to this timer. On solaris such a timer is
dnl available with the syscall gethrtime(). On other OS's a fallback
dnl solution using times() is implemented. (However on e.g. FreeBSD times()
dnl is implemented using gettimeofday so it doesn't make much sense to
dnl use it there...) On second thought, it seems to be safer to do it the
dnl other way around. I.e. only use times() on OS's where we know it will
dnl work...
dnl

AC_DEFUN(ERL_TIME_CORRECTION,
[if test x$ac_cv_func_gethrtime = x; then
  AC_CHECK_FUNC(gethrtime)
fi
if test x$clock_gettime_correction = xunknown; then
	AC_TRY_COMPILE([#include <time.h>],
			[struct timespec ts;
     			 long long result;
			 clock_gettime(CLOCK_MONOTONIC,&ts);
                         result = ((long long) ts.tv_sec) * 1000000000LL + 
			 ((long long) ts.tv_nsec);],
			clock_gettime_compiles=yes,
			clock_gettime_compiles=no)
else
	clock_gettime_compiles=no
fi
			

AC_CACHE_CHECK([how to correct for time adjustments], erl_cv_time_correction,
[
case $clock_gettime_correction in
    yes)
	erl_cv_time_correction=clock_gettime;;	
    no|unknown)
	case $ac_cv_func_gethrtime in
  	    yes)
    		erl_cv_time_correction=hrtime ;;
  	    no)
    		case $host_os in
        	    linux*)
			case $clock_gettime_correction in
			    unknown)
				if test x$clock_gettime_compiles = xyes; then
				    if test X$cross_compiling != Xyes; then
				    	linux_kernel_vsn_=`uname -r`
				    	case $linux_kernel_vsn_ in
					    [[0-1]].*|2.[[0-5]]|2.[[0-5]].*)
					    	erl_cv_time_correction=times ;;
					    *)
					    	erl_cv_time_correction=clock_gettime;;
				    	esac
				    else
					case X$erl_xcomp_linux_clock_gettime_correction in
					    X)
						erl_cv_time_correction=cross;;
					    Xyes|Xno)
						if test $erl_xcomp_linux_clock_gettime_correction = yes; then
						    erl_cv_time_correction=clock_gettime
						else
					    	    erl_cv_time_correction=times
						fi;;
					    *)
						AC_MSG_ERROR([Bad erl_xcomp_linux_clock_gettime_correction value: $erl_xcomp_linux_clock_gettime_correction]);;
					esac
				    fi
				else
				    erl_cv_time_correction=times
				fi
				;;
			     *)				
        			erl_cv_time_correction=times ;;
			esac
			;;
            	    *)
        		erl_cv_time_correction=none ;;
    		esac
    		;;
	esac
	;;
esac
])

xrtlib=""
case $erl_cv_time_correction in
  times)
    AC_DEFINE(CORRECT_USING_TIMES,[],
	[Define if you do not have a high-res. timer & want to use times() instead])
    ;;
  clock_gettime|cross)
    if test $erl_cv_time_correction = cross; then
	erl_cv_time_correction=clock_gettime
	AC_MSG_WARN([result clock_gettime guessed because of cross compilation])
    fi
    xrtlib="-lrt"
    AC_DEFINE(GETHRTIME_WITH_CLOCK_GETTIME,[1],
	[Define if you want to use clock_gettime to simulate gethrtime])
    ;;
esac
dnl
dnl Check if gethrvtime is working, and if to use procfs ioctl
dnl or (yet to be written) write to the procfs ctl file.
dnl

AC_MSG_CHECKING([if gethrvtime works and how to use it])
AC_TRY_RUN([
/* gethrvtime procfs ioctl test */
/* These need to be undef:ed to not break activation of
 * micro level process accounting on /proc/self 
 */
#ifdef _LARGEFILE_SOURCE
#  undef _LARGEFILE_SOURCE
#endif
#ifdef _FILE_OFFSET_BITS
#  undef _FILE_OFFSET_BITS
#endif
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/signal.h>
#include <sys/fault.h>
#include <sys/syscall.h>
#include <sys/procfs.h>
#include <fcntl.h>

int main() {
    long msacct = PR_MSACCT;
    int fd;
    long long start, stop;
    int i;
    pid_t pid = getpid();
    char proc_self[30] = "/proc/";

    sprintf(proc_self+strlen(proc_self), "%lu", (unsigned long) pid);
    if ( (fd = open(proc_self, O_WRONLY)) == -1)
	exit(1);
    if (ioctl(fd, PIOCSET, &msacct) < 0)
	exit(2);
    if (close(fd) < 0)
	exit(3);
    start = gethrvtime();
    for (i = 0; i < 100; i++)
	stop = gethrvtime();
    if (start == 0)
	exit(4);
    if (start == stop)
	exit(5);
    exit(0); return 0;
}
],
erl_gethrvtime=procfs_ioctl,
erl_gethrvtime=false,
[
case X$erl_xcomp_gethrvtime_procfs_ioctl in
    X)
	erl_gethrvtime=cross;;
    Xyes|Xno)
	if test $erl_xcomp_gethrvtime_procfs_ioctl = yes; then
	    erl_gethrvtime=procfs_ioctl
	else
	    erl_gethrvtime=false
	fi;;
    *)
	AC_MSG_ERROR([Bad erl_xcomp_gethrvtime_procfs_ioctl value: $erl_xcomp_gethrvtime_procfs_ioctl]);;
esac
])

case $erl_gethrvtime in
  procfs_ioctl)
	AC_DEFINE(HAVE_GETHRVTIME_PROCFS_IOCTL,[1],
		[define if gethrvtime() works and uses ioctl() to /proc/self])
	AC_MSG_RESULT(uses ioctl to procfs)
	;;
  *)
	if test $erl_gethrvtime = cross; then
	    erl_gethrvtime=false
	    AC_MSG_RESULT(cross)
	    AC_MSG_WARN([result 'not working' guessed because of cross compilation])
	else
	    AC_MSG_RESULT(not working)
	fi

	dnl
	dnl Check if clock_gettime (linux) is working
	dnl

	AC_MSG_CHECKING([if clock_gettime can be used to get process CPU time])
	save_libs=$LIBS
	LIBS="-lrt"
	AC_TRY_RUN([
	#include <stdlib.h>
	#include <unistd.h>
	#include <string.h>
	#include <stdio.h>
	#include <time.h>
	int main() {
	    long long start, stop;
	    int i;
	    struct timespec tp;

	    if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &tp) < 0)
	      exit(1);
	    start = ((long long)tp.tv_sec * 1000000000LL) + (long long)tp.tv_nsec;
	    for (i = 0; i < 100; i++)
	      clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &tp);
	    stop = ((long long)tp.tv_sec * 1000000000LL) + (long long)tp.tv_nsec;
	    if (start == 0)
	      exit(4);
	    if (start == stop)
	      exit(5);
	    exit(0); return 0;
	  }
	],
	erl_clock_gettime=yes,
	erl_clock_gettime=no,
	[
	case X$erl_xcomp_clock_gettime_cpu_time in
	    X) erl_clock_gettime=cross;;
	    Xyes|Xno) erl_clock_gettime=$erl_xcomp_clock_gettime_cpu_time;;
	    *) AC_MSG_ERROR([Bad erl_xcomp_clock_gettime_cpu_time value: $erl_xcomp_clock_gettime_cpu_time]);;
	esac
	])
	LIBS=$save_libs
	case $host_os in
		linux*)
			AC_MSG_RESULT([no; not stable])
			LIBRT=$xrtlib
			;;
		*)
			AC_MSG_RESULT($erl_clock_gettime)
			case $erl_clock_gettime in
	  			yes)
					AC_DEFINE(HAVE_CLOCK_GETTIME,[],
						  [define if clock_gettime() works for getting process time])
					LIBRT=-lrt
					;;
	  			cross)
					erl_clock_gettime=no
					AC_MSG_WARN([result no guessed because of cross compilation])
					LIBRT=$xrtlib
					;;
	  			*)
					LIBRT=$xrtlib
					;;
			esac
			;;
	esac
	AC_SUBST(LIBRT)
	;;
esac
])dnl

dnl ERL_TRY_LINK_JAVA(CLASSES, FUNCTION-BODY
dnl                   [ACTION_IF_FOUND [, ACTION-IF-NOT-FOUND]])
dnl Freely inspired by AC_TRY_LINK. (Maybe better to create a 
dnl AC_LANG_JAVA instead...)
AC_DEFUN(ERL_TRY_LINK_JAVA,
[java_link='$JAVAC conftest.java 1>&AC_FD_CC'
changequote(�, �)dnl
cat > conftest.java <<EOF
�$1�
class conftest { public static void main(String[] args) {
   �$2�
   ; return; }}
EOF
changequote([, ])dnl
if AC_TRY_EVAL(java_link) && test -s conftest.class; then
   ifelse([$3], , :, [rm -rf conftest*
   $3])
else
   echo "configure: failed program was:" 1>&AC_FD_CC
   cat conftest.java 1>&AC_FD_CC
   echo "configure: PATH was $PATH" 1>&AC_FD_CC
ifelse([$4], , , [  rm -rf conftest*
  $4
])dnl
fi
rm -f conftest*])
#define UNSAFE_MASK  0xc0000000 /* Mask for bits that must be constant */