aboutsummaryrefslogtreecommitdiff
path: root/libiberty/aclocal.m4
blob: 643939e9d78e7602e82d2c52fb41bb834445cc91 (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
sinclude(../config/acx.m4)
sinclude(../config/no-executables.m4)
sinclude(../config/warnings.m4)

dnl See whether strncmp reads past the end of its string parameters.
dnl On some versions of SunOS4 at least, strncmp reads a word at a time
dnl but erroneously reads past the end of strings.  This can cause
dnl a SEGV in some cases.
AC_DEFUN(libiberty_AC_FUNC_STRNCMP,
[AC_REQUIRE([AC_FUNC_MMAP])
AC_CACHE_CHECK([for working strncmp], ac_cv_func_strncmp_works,
[AC_TRY_RUN([
/* Test by Jim Wilson and Kaveh Ghazi.
   Check whether strncmp reads past the end of its string parameters. */
#include <sys/types.h>

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif

#ifndef MAP_ANON
#ifdef MAP_ANONYMOUS
#define MAP_ANON MAP_ANONYMOUS
#else
#define MAP_ANON MAP_FILE
#endif
#endif

#ifndef MAP_FILE
#define MAP_FILE 0
#endif
#ifndef O_RDONLY
#define O_RDONLY 0
#endif

#define MAP_LEN 0x10000

main ()
{
#if defined(HAVE_MMAP) || defined(HAVE_MMAP_ANYWHERE)
  char *p;
  int dev_zero;

  dev_zero = open ("/dev/zero", O_RDONLY);
  if (dev_zero < 0)
    exit (1);
  
  p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
		     MAP_ANON|MAP_PRIVATE, dev_zero, 0);
  if (p == (char *)-1)
    p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
		       MAP_ANON|MAP_PRIVATE, -1, 0);
  if (p == (char *)-1)
    exit (2);
  else
    {
      char *string = "__si_type_info";
      char *q = (char *) p + MAP_LEN - strlen (string) - 2;
      char *r = (char *) p + 0xe;

      strcpy (q, string);
      strcpy (r, string);
      strncmp (r, q, 14);
    }
#endif /* HAVE_MMAP || HAVE_MMAP_ANYWHERE */
  exit (0);
}
], ac_cv_func_strncmp_works=yes, ac_cv_func_strncmp_works=no,
  ac_cv_func_strncmp_works=no)
rm -f core core.* *.core])
if test $ac_cv_func_strncmp_works = no ; then
  AC_LIBOBJ([strncmp])
fi
])

dnl See if errno must be declared even when <errno.h> is included.
AC_DEFUN(libiberty_AC_DECLARE_ERRNO,
[AC_CACHE_CHECK(whether errno must be declared, libiberty_cv_declare_errno,
[AC_TRY_COMPILE(
[#include <errno.h>],
[int x = errno;],
libiberty_cv_declare_errno=no,
libiberty_cv_declare_errno=yes)])
if test $libiberty_cv_declare_errno = yes
then AC_DEFINE(NEED_DECLARATION_ERRNO, 1,
  [Define if errno must be declared even when <errno.h> is included.])
fi
])

dnl See whether we need a declaration for a function.
AC_DEFUN(libiberty_NEED_DECLARATION,
[AC_MSG_CHECKING([whether $1 must be declared])
AC_CACHE_VAL(libiberty_cv_decl_needed_$1,
[AC_TRY_COMPILE([
#include "confdefs.h"
#include <stdio.h>
#ifdef HAVE_STRING_H
#include <string.h>
#else
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif],
[char *(*pfn) = (char *(*)) $1],
libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)])
AC_MSG_RESULT($libiberty_cv_decl_needed_$1)
if test $libiberty_cv_decl_needed_$1 = yes; then
  AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
            [Define if $1 is not declared in system header files.])
fi
])dnl

# We always want a C version of alloca() compiled into libiberty,
# because native-compiler support for the real alloca is so !@#$%
# unreliable that GCC has decided to use it only when being compiled
# by GCC.  This is the part of AC_FUNC_ALLOCA that calculates the
# information alloca.c needs.
AC_DEFUN(libiberty_AC_FUNC_C_ALLOCA,
[AC_CACHE_CHECK(whether alloca needs Cray hooks, ac_cv_os_cray,
[AC_EGREP_CPP(webecray,
[#if defined(CRAY) && ! defined(CRAY2)
webecray
#else
wenotbecray
#endif
], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
if test $ac_cv_os_cray = yes; then
  for ac_func in _getb67 GETB67 getb67; do
    AC_CHECK_FUNC($ac_func, 
      [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func, 
  [Define to one of _getb67, GETB67, getb67 for Cray-2 and Cray-YMP
   systems. This function is required for alloca.c support on those
   systems.])  break])
  done
fi

AC_CACHE_CHECK(stack direction for C alloca, ac_cv_c_stack_direction,
[AC_TRY_RUN([find_stack_direction ()
{
  static char *addr = 0;
  auto char dummy;
  if (addr == 0)
    {
      addr = &dummy;
      return find_stack_direction ();
    }
  else
    return (&dummy > addr) ? 1 : -1;
}
main ()
{
  exit (find_stack_direction() < 0);
}], 
  ac_cv_c_stack_direction=1,
  ac_cv_c_stack_direction=-1,
  ac_cv_c_stack_direction=0)])
AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction,
  [Define if you know the direction of stack growth for your system;
   otherwise it will be automatically deduced at run-time.
        STACK_DIRECTION > 0 => grows toward higher addresses
        STACK_DIRECTION < 0 => grows toward lower addresses
        STACK_DIRECTION = 0 => direction of growth unknown])
])

# AC_LANG_FUNC_LINK_TRY(C)(FUNCTION)
# ----------------------------------
# Don't include <ctype.h> because on OSF/1 3.0 it includes
# <sys/types.h> which includes <sys/select.h> which contains a
# prototype for select.  Similarly for bzero.
#
# This test used to merely assign f=$1 in main(), but that was
# optimized away by HP unbundled cc A.05.36 for ia64 under +O3,
# presumably on the basis that there's no need to do that store if the
# program is about to exit.  Conversely, the AIX linker optimizes an
# unused external declaration that initializes f=$1.  So this test
# program has both an external initialization of f, and a use of f in
# main that affects the exit status.
#
m4_define([AC_LANG_FUNC_LINK_TRY(C)],
[AC_LANG_PROGRAM(
[/* System header to define __stub macros and hopefully few prototypes,
    which can conflict with char $1 (); below.
    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
    <limits.h> exists even on freestanding compilers.  Under hpux,
    including <limits.h> includes <sys/time.h> and causes problems
    checking for functions defined therein.  */
#if defined (__STDC__) && !defined (_HPUX_SOURCE)
# include <limits.h>
#else
# include <assert.h>
#endif
/* 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
char (*f) () = $1;
#endif
#ifdef __cplusplus
}
#endif
], [return f != $1;])])