summaryrefslogtreecommitdiff
path: root/acinclude.m4
blob: da1b971dfa796036f90ab895b3175018b1c9a071 (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
dnl -*- Autoconf -*-

dnl Copyright (C) 1997,1999-2002,2004,2006-2011,2013,2018-2019,2022
dnl   Free Software Foundation, Inc.
dnl
dnl This file is part of GUILE
dnl
dnl GUILE is free software; you can redistribute it and/or modify it under
dnl the terms of the GNU Lesser General Public License as published by the
dnl Free Software Foundation; either version 3, or (at your option) any
dnl later version.
dnl
dnl GUILE is distributed in the hope that it will be useful, but WITHOUT
dnl ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
dnl FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
dnl License for more details.
dnl
dnl You should have received a copy of the GNU Lesser General Public
dnl License along with GUILE; see the file COPYING.LESSER.  If not, write
dnl to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
dnl Floor, Boston, MA 02110-1301, USA.


dnl  On the NeXT, #including <utime.h> doesn't give you a definition for
dnl  struct utime, unless you #define _POSIX_SOURCE.

AC_DEFUN([GUILE_STRUCT_UTIMBUF], [
  AC_CACHE_CHECK([whether we need POSIX to get struct utimbuf],
    guile_cv_struct_utimbuf_needs_posix,
    [AC_PREPROC_IFELSE([AC_LANG_SOURCE([[
#ifdef __EMX__
#include <sys/utime.h>
#else
#include <utime.h>
#endif
struct utime blah;
]])],
[guile_cv_struct_utimbuf_needs_posix=no],
[guile_cv_struct_utimbuf_needs_posix=yes])])
  if test "$guile_cv_struct_utimbuf_needs_posix" = yes; then
     AC_DEFINE([UTIMBUF_NEEDS_POSIX], 1,
       [Define this if <utime.h> doesn't define struct utimbuf unless
        _POSIX_SOURCE is defined.  See GUILE_STRUCT_UTIMBUF in aclocal.m4.])
  fi])


dnl This is needed when we want to check for the same function repeatedly
dnl with other parameters, such as libraries, varying.
dnl
dnl GUILE_NAMED_CHECK_FUNC(FUNCTION, TESTNAME,
dnl                        [ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]])
AC_DEFUN([GUILE_NAMED_CHECK_FUNC],
[AC_MSG_CHECKING([for $1])
AC_CACHE_VAL(ac_cv_func_$1_$2,
[AC_LINK_IFELSE([AC_LANG_PROGRAM([[dnl Don't include <ctype.h> because on OSF/1 3.0 it includes <sys/types.h>
dnl which includes <sys/select.h> which contains a prototype for
dnl select.  Similarly for bzero.
/* System header to define __stub macros and hopefully few prototypes,
    which can conflict with char $1(); below.  */
#include <assert.h>
/* Override any gcc2 internal prototype to avoid an error.  */
#ifdef __cplusplus
extern "C"
#endif
/* We use char because int might match the return type of a gcc2
    builtin and then its argument prototype would still apply.  */
char $1();
]], [[
/* The GNU C library defines this for functions which it implements
    to always fail with ENOSYS.  Some functions are actually named
    something starting with __ and the normal name is an alias.  */
#if defined (__stub_$1) || defined (__stub___$1)
choke me
#else
$1();
#endif
]])],[eval "ac_cv_func_$1_$2=yes"],[eval "ac_cv_func_$1_$2=no"])])
if eval "test \"`echo '$ac_cv_func_'$1'_'$2`\" = yes"; then
  AC_MSG_RESULT(yes)
  ifelse([$3], , :, [$3])
else
  AC_MSG_RESULT(no)
ifelse([$4], , , [$4
])dnl
fi
])




dnl Available from the Autoconf Macro Archive at:
dnl http://autoconf-archive.cryp.to/acx_pthread.html
dnl
AC_DEFUN([ACX_PTHREAD], [
AC_REQUIRE([AC_CANONICAL_HOST])
AC_LANG_SAVE
AC_LANG([C])
acx_pthread_ok=no

# We used to check for pthread.h first, but this fails if pthread.h
# requires special compiler flags (e.g. on True64 or Sequent).
# It gets checked for in the link test anyway.

# First of all, check if the user has set any of the PTHREAD_LIBS,
# etcetera environment variables, and if threads linking works using
# them:
if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then
        save_CFLAGS="$CFLAGS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
        save_LIBS="$LIBS"
        LIBS="$PTHREAD_LIBS $LIBS"
        AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS])
        AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes)
        AC_MSG_RESULT($acx_pthread_ok)
        if test x"$acx_pthread_ok" = xno; then
                PTHREAD_LIBS=""
                PTHREAD_CFLAGS=""
        fi
        LIBS="$save_LIBS"
        CFLAGS="$save_CFLAGS"
fi

# We must check for the threads library under a number of different
# names; the ordering is very important because some systems
# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
# libraries is broken (non-POSIX).

# Create a list of thread flags to try.  Items starting with a "-" are
# C compiler flags, and other items are library names, except for "none"
# which indicates that we try without any flags at all, and "pthread-config"
# which is a program returning the flags for the Pth emulation library.

acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"

# The ordering *is* (sometimes) important.  Some notes on the
# individual items follow:

# pthreads: AIX (must check this before -lpthread)
# none: in case threads are in libc; should be tried before -Kthread and
#       other compiler flags to prevent continual compiler warnings
# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads)
# -pthreads: Solaris/gcc
# -mthreads: Mingw32/gcc, Lynx/gcc
# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
#      doesn't hurt to check since this sometimes defines pthreads too;
#      also defines -D_REENTRANT)
#      ... -mt is also the pthreads flag for HP/aCC
# pthread: Linux, etcetera
# --thread-safe: KAI C++
# pthread-config: use pthread-config program (for GNU Pth library)

case "${host_cpu}-${host_os}" in
        *solaris*)

        # On Solaris (at least, for some versions), libc contains stubbed
        # (non-functional) versions of the pthreads routines, so link-based
        # tests will erroneously succeed.  (We need to link with -pthreads/-mt/
        # -lpthread.)  (The stubs are missing pthread_cleanup_push, or rather
        # a function called by this macro, so we could check for that, but
        # who knows whether they'll stub that too in a future libc.)  So,
        # we'll just look for -pthreads and -lpthread first:

        acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags"
        ;;
esac

if test x"$acx_pthread_ok" = xno; then
for flag in $acx_pthread_flags; do

        case $flag in
                none)
                AC_MSG_CHECKING([whether pthreads work without any flags])
                ;;

                -*)
                AC_MSG_CHECKING([whether pthreads work with $flag])
                PTHREAD_CFLAGS="$flag"
                ;;

                pthread-config)
                AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no)
                if test x"$acx_pthread_config" = xno; then continue; fi
                PTHREAD_CFLAGS="`pthread-config --cflags`"
                PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
                ;;

                *)
                AC_MSG_CHECKING([for the pthreads library -l$flag])
                PTHREAD_LIBS="-l$flag"
                ;;
        esac

        save_LIBS="$LIBS"
        save_CFLAGS="$CFLAGS"
        LIBS="$PTHREAD_LIBS $LIBS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"

        # Check for various functions.  We must include pthread.h,
        # since some functions may be macros.  (On the Sequent, we
        # need a special flag -Kthread to make this header compile.)
        # We check for pthread_join because it is in -lpthread on IRIX
        # while pthread_create is in libc.  We check for pthread_attr_init
        # due to DEC craziness with -lpthreads.  We check for
        # pthread_cleanup_push because it is one of the few pthread
        # functions on Solaris that doesn't have a non-functional libc stub.
        # We try pthread_create on general principles.
        AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]], [[pthread_t th; pthread_join(th, 0);
                     pthread_attr_init(0); pthread_cleanup_push(0, 0);
                     pthread_create(0,0,0,0); pthread_cleanup_pop(0); ]])],[acx_pthread_ok=yes],[])

        LIBS="$save_LIBS"
        CFLAGS="$save_CFLAGS"

        AC_MSG_RESULT($acx_pthread_ok)
        if test "x$acx_pthread_ok" = xyes; then
                break;
        fi

        PTHREAD_LIBS=""
        PTHREAD_CFLAGS=""
done
fi

# Various other checks:
if test "x$acx_pthread_ok" = xyes; then
        save_LIBS="$LIBS"
        LIBS="$PTHREAD_LIBS $LIBS"
        save_CFLAGS="$CFLAGS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"

        # Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
        AC_MSG_CHECKING([for joinable pthread attribute])
        attr_name=unknown
        for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
            AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]], [[int attr=$attr; return attr;]])],[attr_name=$attr; break],[])
        done
        AC_MSG_RESULT($attr_name)
        if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then
            AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE], $attr_name,
                               [Define to necessary symbol if this constant
                                uses a non-standard name on your system.])
        fi

        AC_MSG_CHECKING([if more special flags are required for pthreads])
        flag=no
        case "${host_cpu}-${host_os}" in
            *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";;
            *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";;
        esac
        AC_MSG_RESULT(${flag})
        if test "x$flag" != xno; then
            PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
        fi

        LIBS="$save_LIBS"
        CFLAGS="$save_CFLAGS"

        # More AIX lossage: must compile with xlc_r or cc_r
        if test x"$GCC" != xyes; then
          AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC})
        else
          PTHREAD_CC=$CC
        fi
else
        PTHREAD_CC="$CC"
fi

AC_SUBST(PTHREAD_LIBS)
AC_SUBST(PTHREAD_CFLAGS)
AC_SUBST(PTHREAD_CC)

# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
if test x"$acx_pthread_ok" = xyes; then
        ifelse([$1],,AC_DEFINE([HAVE_PTHREAD],1,[Define if you have POSIX threads libraries and header files.]),[$1])
        :
else
        acx_pthread_ok=no
        $2
fi
AC_LANG_RESTORE
])dnl ACX_PTHREAD

dnl GUILE_GNU_LD_RELRO
dnl
dnl Check whether GNU ld's read-only relocations (the `PT_GNU_RELRO'
dnl ELF segment header) are supported.  This allows things like
dnl statically allocated cells (1) to eventually be remapped read-only
dnl by the loader, and (2) to be identified as pointerless by the
dnl garbage collector.  Substitute `GNU_LD_FLAGS' with the relevant
dnl flags.
AC_DEFUN([GUILE_GNU_LD_RELRO], [
  AC_MSG_CHECKING([whether the linker understands `-z relro'])

  GNU_LD_FLAGS="-Wl,-z -Wl,relro"

  save_LDFLAGS="$LDFLAGS"
  LDFLAGS="$LDFLAGS $GNU_LD_FLAGS"
  AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
    [AC_MSG_RESULT([yes])],
    [AC_MSG_RESULT([no])
     GNU_LD_FLAGS=""])
  LDFLAGS="$save_LDFLAGS"

  AC_SUBST([GNU_LD_FLAGS])
])

dnl GUILE_THREAD_LOCAL_STORAGE
dnl
dnl Check for compiler thread-local storage (TLS) support.
AC_DEFUN([GUILE_THREAD_LOCAL_STORAGE], [
  AC_REQUIRE([AC_CANONICAL_HOST])

  AC_CACHE_CHECK([whether the `__thread' storage class is available],
    [ac_cv_have_thread_storage_class],
    [dnl On some systems, e.g., NetBSD 5.0 with GCC 4.1, `__thread' is
     dnl properly compiled but fails to link due to the lack of TLS
     dnl support in the C library.  Thus we try to link, not just
     dnl compile.  Unfortunately, this test is not enough, so we
     dnl explicitly check for known-broken systems.  See
     dnl http://lists.gnu.org/archive/html/guile-devel/2009-10/msg00138.html
     dnl for details.
     dnl
     dnl Known broken systems includes:
     dnl   - x86_64-unknown-netbsd5.0.
     dnl   - x86_64-unknown-netbsd5.1
     dnl   - sparc-sun-solaris2.8
     dnl
     dnl On `x86_64-unknown-freebsd8.0', thread-local storage appears to
     dnl be reclaimed at the wrong time, leading to a segfault when
     dnl running `threads.test'.  So disable it.
     case "$enable_shared--$host_os" in
       [yes--netbsd[0-5].[0-9]*|yes--solaris2.8|yes--freebsd[0-8]*])
         ac_cv_have_thread_storage_class="no"
         ;;
       *)
         AC_LINK_IFELSE([AC_LANG_PROGRAM([__thread int tls_integer;],
                          [tls_integer = 123;])],
           [ac_cv_have_thread_storage_class="yes"],
           [ac_cv_have_thread_storage_class="no"])
         ;;
     esac])

  if test "x$ac_cv_have_thread_storage_class" = "xyes"; then
     SCM_I_GSC_HAVE_THREAD_STORAGE_CLASS=1
  else
     SCM_I_GSC_HAVE_THREAD_STORAGE_CLASS=0
  fi

  AC_SUBST([SCM_I_GSC_HAVE_THREAD_STORAGE_CLASS])
])

dnl GUILE_READLINE
dnl
dnl Check all the things needed by `guile-readline', the Readline
dnl bindings.
AC_DEFUN([GUILE_READLINE], [
  for termlib in ncurses curses termcap terminfo termlib pdcurses ; do
     AC_CHECK_LIB(${termlib}, [tgoto],
       [READLINE_LIBS="-l${termlib} $READLINE_LIBS"; break])
  done

  AC_LIB_LINKFLAGS([readline])

  if test "x$LTLIBREADLINE" = "x"; then
    AC_MSG_WARN([GNU Readline was not found on your system.])
  else
    rl_save_LIBS="$LIBS"
    LIBS="$LIBREADLINE $READLINE_LIBS $LIBS"

    AC_CHECK_FUNCS([siginterrupt rl_clear_signals rl_cleanup_after_signal])

    dnl Check for modern readline naming
    AC_CHECK_FUNCS([rl_filename_completion_function])
    AC_CHECK_DECLS([rl_catch_signals, rl_catch_sigwinch], [], [],
                   [[#include <stdio.h>]
                    [#include <readline/readline.h>]])

    dnl Check rl_get_keymap_name instead of rl_get_keymap because some
    dnl systems only have the latter and the feature needs both.
    dnl We only use this for deciding whether to install paren matching on
    dnl the Guile command line (when using readline for input), so it's
    dnl completely optional.
    AC_CHECK_FUNCS([rl_get_keymap_name])

    AC_CACHE_CHECK([for rl_getc_function pointer in readline],
		     ac_cv_var_rl_getc_function,
		     [AC_LINK_IFELSE([AC_LANG_PROGRAM([[
    #include <stdio.h>
    #include <readline/readline.h>]],
      [[printf ("%ld", (long) rl_getc_function)]])],
      [ac_cv_var_rl_getc_function=yes],
      [ac_cv_var_rl_getc_function=no])])
    if test "${ac_cv_var_rl_getc_function}" = "yes"; then
      AC_DEFINE([HAVE_RL_GETC_FUNCTION], 1,
	[Define if your readline library has the rl_getc_function variable.])
    fi

    if test $ac_cv_var_rl_getc_function = no; then
      AC_MSG_WARN([*** GNU Readline is too old on your system.])
      AC_MSG_WARN([*** You need readline version 2.1 or later.])
      LTLIBREADLINE=""
      LIBREADLINE=""
    fi

    LIBS="$rl_save_LIBS"

    READLINE_LIBS="$LTLIBREADLINE $READLINE_LIBS"
  fi

  AM_CONDITIONAL([HAVE_READLINE], [test "x$LTLIBREADLINE" != "x"])

  AC_CHECK_FUNCS([strdup])

  AC_SUBST([READLINE_LIBS])
])

dnl GUILE_LIBUNISTRING_WITH_ICONV_SUPPORT
dnl
dnl Check whether libunistring has iconv support.  When it lacks iconv
dnl support, `mem_iconveh' returns -1 (ENOSYS) and conversions from one
dnl codeset to another do not work.
AC_DEFUN([GUILE_LIBUNISTRING_WITH_ICONV_SUPPORT], [
  AC_CACHE_CHECK([whether libunistring was built with iconv support],
    [ac_cv_libunistring_with_iconv_support], [
     save_LIBS=$LIBS
     LIBS="$LIBS $LIBUNISTRING"
     AC_RUN_IFELSE([AC_LANG_SOURCE([[
       #include <uniconv.h>
       #include <unistring/iconveh.h>
       int
       main (int argc, char *argv[])
       {
	 size_t result_size;
	 return (NULL == u32_conv_from_encoding ("ASCII", iconveh_question_mark,
						 "a", 1,
						 NULL, NULL, &result_size));
       }
     ]])],
	 [ac_cv_libunistring_with_iconv_support=yes],
	 [ac_cv_libunistring_with_iconv_support=no],
	 [ac_cv_libunistring_with_iconv_support=yes])
     LIBS=$save_LIBS
   ])
])

dnl GUILE_UNISTRING_CONSTANT NAME
dnl
dnl Determine the compile-time value of NAME and define/substitute
dnl `SCM_I_GSC_NAME'.
AC_DEFUN([GUILE_UNISTRING_CONSTANT], [
  m4_pushdef([UPPER_CASE_NAME],
    [m4_translit([$1],[abcdefghijklmnopqrstuvwxyz],
                  [ABCDEFGHIJKLMNOPQRSTUVWXYZ])])

  AC_CACHE_CHECK([the value of `$1'], [ac_cv_]$1, [
    AC_COMPUTE_INT([ac_cv_]$1, [$1],
      [AC_INCLUDES_DEFAULT
#include <uniconv.h>
],
      [AC_MSG_ERROR([failed to determine the value of `$1'])])
  ])

  [SCM_I_GSC_]UPPER_CASE_NAME="$ac_cv_[]$1"
  AC_SUBST([SCM_I_GSC_]UPPER_CASE_NAME)
  m4_popdef([UPPER_CASE_NAME])])

dnl GUILE_UNISTRING_ICONVEH_VALUES
dnl
dnl Determine the values of the `iconveh_' libunistring constants.
AC_DEFUN([GUILE_UNISTRING_ICONVEH_VALUES], [
  GUILE_UNISTRING_CONSTANT([iconveh_error])
  GUILE_UNISTRING_CONSTANT([iconveh_question_mark])
  GUILE_UNISTRING_CONSTANT([iconveh_escape_sequence])
])

dnl GUILE_CHECK_VERSION
dnl
dnl Ensure that $GUILE_FOR_BUILD has the same version as ourselves.
AC_DEFUN([GUILE_CHECK_VERSION], [
  if ! "$GUILE_FOR_BUILD" --version > /dev/null 2>&1; then
     AC_MSG_ERROR([failed to run `$GUILE_FOR_BUILD'])
  fi

  dnl Use MAJOR.MINOR.MICRO instead of (version) so that developers can
  dnl freely shoot themselves in the foot by using, say, 2.0.3.80 and
  dnl 2.0.3.42.
  AC_CACHE_CHECK([the version of $GUILE_FOR_BUILD],
    [ac_cv_guile_for_build_version],
    [ac_cv_guile_for_build_version="`"$GUILE_FOR_BUILD" \
       -c '(format #t "~a.~a.~a" (major-version) (minor-version) (micro-version))'`"
    ])

  if test "$ac_cv_guile_for_build_version" != \
       "$GUILE_MAJOR_VERSION.$GUILE_MINOR_VERSION.$GUILE_MICRO_VERSION"
  then
      AC_MSG_ERROR([building Guile $PACKAGE_VERSION but `$GUILE_FOR_BUILD' has version $ac_cv_guile_for_build_version"])
  fi
])

dnl GUILE_CHECK_GUILE_FOR_BUILD
dnl
dnl When cross-compiling, ensure that $GUILE_FOR_BUILD is suitable.
AC_DEFUN([GUILE_CHECK_GUILE_FOR_BUILD], [
  if test "$cross_compiling" = "yes"; then
    if test "x$GUILE_FOR_BUILD" = "x"; then
      AC_PATH_PROG([GUILE_FOR_BUILD], [guile], [not-found])
      if test "$GUILE_FOR_BUILD" = "not-found"; then
        AC_MSG_ERROR([a native Guile $PACKAGE_VERSION is required to cross-build Guile])
      fi
    else
      GUILE_FOR_BUILD=$(which "$GUILE_FOR_BUILD" || echo "$GUILE_FOR_BUILD")
    fi
    AC_MSG_CHECKING([guile for build])
    AC_MSG_RESULT([$GUILE_FOR_BUILD])

    dnl Since there is currently no distinction between the run-time
    dnl search path, %load-path, and the compiler's search path,
    dnl $GUILE_FOR_BUILD must be a native build of the very same version.
    GUILE_CHECK_VERSION
  else
    GUILE_FOR_BUILD='this-value-will-never-be-used'
  fi

  AC_ARG_VAR([GUILE_FOR_BUILD], [guile for the build system])
  AM_SUBST_NOTMAKE([GUILE_FOR_BUILD])
])

dnl Declare file $1 to be a script that needs configuring,
dnl and arrange to make it executable in the process.
AC_DEFUN([GUILE_CONFIG_SCRIPT],[AC_CONFIG_FILES([$1],[chmod +x $1])])

AC_DEFUN([GUILE_ENABLE_JIT], [
  JIT_AVAILABLE=no
  AC_MSG_CHECKING([if JIT code generation supported for target CPU])
  case "$target_cpu" in
    i?86|x86_64|amd64)    JIT_AVAILABLE=yes ;;
    *arm*)                JIT_AVAILABLE=yes ;;
    aarch64)              JIT_AVAILABLE=yes ;;
    *)                                      ;;
  esac
  AC_MSG_RESULT($JIT_AVAILABLE)

  AC_ARG_ENABLE(jit,
    [AS_HELP_STRING([--enable-jit[=yes/no/auto]],
                    [enable just-in-time code generation [default=auto]])])

  AC_MSG_CHECKING([whether to enable JIT code generation])
  case "x$enable_jit" in
    xy*) enable_jit=yes ;;
    xn*) enable_jit=no ;;
    xa* | x) enable_jit=$JIT_AVAILABLE ;;
    *)  AC_MSG_ERROR(bad value $enable_jit for --enable-jit) ;;
  esac
  AC_MSG_RESULT($enable_jit)

  if test $enable_jit = yes; then
    if test $JIT_AVAILABLE = no; then
      AC_MSG_ERROR(
        [JIT explicitly enabled with --enable-jit but not supported on $target_cpu])
    fi
    AC_CHECK_FUNCS(mremap ffsl isnan isinf,,)
  fi

  AM_CONDITIONAL([ENABLE_JIT], [test "$enable_jit" = "yes"])
  ENABLE_JIT_VAL=$(if test "$enable_jit" = "yes"; then echo 1; else echo 0; fi)
  AC_DEFINE_UNQUOTED([ENABLE_JIT], [$ENABLE_JIT_VAL],
    [Define to 1 if JIT compilation is enabled, or 0 otherwise.])
])