xref: /netbsd-src/external/gpl3/gdb.old/dist/libiberty/aclocal.m4 (revision 0a3071956a3a9fdebdbf7f338cf2d439b45fc728)
1sinclude(../config/acx.m4)
2sinclude(../config/cet.m4)
3sinclude(../config/enable.m4)
4sinclude(../config/no-executables.m4)
5sinclude(../config/override.m4)
6sinclude(../config/picflag.m4)
7sinclude(../config/warnings.m4)
8
9dnl See whether strncmp reads past the end of its string parameters.
10dnl On some versions of SunOS4 at least, strncmp reads a word at a time
11dnl but erroneously reads past the end of strings.  This can cause
12dnl a SEGV in some cases.
13AC_DEFUN(libiberty_AC_FUNC_STRNCMP,
14[AC_REQUIRE([AC_FUNC_MMAP])
15AC_CACHE_CHECK([for working strncmp], ac_cv_func_strncmp_works,
16[AC_TRY_RUN([
17/* Test by Jim Wilson and Kaveh Ghazi.
18   Check whether strncmp reads past the end of its string parameters. */
19#include <sys/types.h>
20
21#ifdef HAVE_FCNTL_H
22#include <fcntl.h>
23#endif
24
25#ifdef HAVE_SYS_MMAN_H
26#include <sys/mman.h>
27#endif
28
29#ifndef MAP_ANON
30#ifdef MAP_ANONYMOUS
31#define MAP_ANON MAP_ANONYMOUS
32#else
33#define MAP_ANON MAP_FILE
34#endif
35#endif
36
37#ifndef MAP_FILE
38#define MAP_FILE 0
39#endif
40#ifndef O_RDONLY
41#define O_RDONLY 0
42#endif
43
44#define MAP_LEN 0x10000
45
46main ()
47{
48#if defined(HAVE_MMAP) || defined(HAVE_MMAP_ANYWHERE)
49  char *p;
50  int dev_zero;
51
52  dev_zero = open ("/dev/zero", O_RDONLY);
53  if (dev_zero < 0)
54    exit (1);
55
56  p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
57		     MAP_ANON|MAP_PRIVATE, dev_zero, 0);
58  if (p == (char *)-1)
59    p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
60		       MAP_ANON|MAP_PRIVATE, -1, 0);
61  if (p == (char *)-1)
62    exit (2);
63  else
64    {
65      char *string = "__si_type_info";
66      char *q = (char *) p + MAP_LEN - strlen (string) - 2;
67      char *r = (char *) p + 0xe;
68
69      strcpy (q, string);
70      strcpy (r, string);
71      strncmp (r, q, 14);
72    }
73#endif /* HAVE_MMAP || HAVE_MMAP_ANYWHERE */
74  exit (0);
75}
76], ac_cv_func_strncmp_works=yes, ac_cv_func_strncmp_works=no,
77  ac_cv_func_strncmp_works=yes)
78rm -f core core.* *.core])
79if test $ac_cv_func_strncmp_works = no ; then
80  AC_LIBOBJ([strncmp])
81fi
82])
83
84dnl See if errno must be declared even when <errno.h> is included.
85AC_DEFUN(libiberty_AC_DECLARE_ERRNO,
86[AC_CACHE_CHECK(whether errno must be declared, libiberty_cv_declare_errno,
87[AC_TRY_COMPILE(
88[#include <errno.h>],
89[int x = errno;],
90libiberty_cv_declare_errno=no,
91libiberty_cv_declare_errno=yes)])
92if test $libiberty_cv_declare_errno = yes
93then AC_DEFINE(NEED_DECLARATION_ERRNO, 1,
94  [Define if errno must be declared even when <errno.h> is included.])
95fi
96])
97
98dnl See whether we need a declaration for a function.
99AC_DEFUN(libiberty_NEED_DECLARATION,
100[AC_MSG_CHECKING([whether $1 must be declared])
101AC_CACHE_VAL(libiberty_cv_decl_needed_$1,
102[AC_TRY_COMPILE([
103#include "confdefs.h"
104#include <stdio.h>
105#ifdef HAVE_STRING_H
106#include <string.h>
107#else
108#ifdef HAVE_STRINGS_H
109#include <strings.h>
110#endif
111#endif
112#ifdef HAVE_STDLIB_H
113#include <stdlib.h>
114#endif
115#ifdef HAVE_UNISTD_H
116#include <unistd.h>
117#endif],
118[char *(*pfn) = (char *(*)) $1],
119libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)])
120AC_MSG_RESULT($libiberty_cv_decl_needed_$1)
121if test $libiberty_cv_decl_needed_$1 = yes; then
122  AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
123            [Define if $1 is not declared in system header files.])
124fi
125])dnl
126
127# We always want a C version of alloca() compiled into libiberty,
128# because native-compiler support for the real alloca is so !@#$%
129# unreliable that GCC has decided to use it only when being compiled
130# by GCC.  This is the part of AC_FUNC_ALLOCA that calculates the
131# information alloca.c needs.
132AC_DEFUN(libiberty_AC_FUNC_C_ALLOCA,
133[AC_CACHE_CHECK(whether alloca needs Cray hooks, ac_cv_os_cray,
134[AC_EGREP_CPP(webecray,
135[#if defined(CRAY) && ! defined(CRAY2)
136webecray
137#else
138wenotbecray
139#endif
140], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
141if test $ac_cv_os_cray = yes; then
142  for ac_func in _getb67 GETB67 getb67; do
143    AC_CHECK_FUNC($ac_func,
144      [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func,
145  [Define to one of _getb67, GETB67, getb67 for Cray-2 and Cray-YMP
146   systems. This function is required for alloca.c support on those
147   systems.])  break])
148  done
149fi
150
151AC_CACHE_CHECK(stack direction for C alloca, ac_cv_c_stack_direction,
152[AC_TRY_RUN([find_stack_direction ()
153{
154  static char *addr = 0;
155  auto char dummy;
156  if (addr == 0)
157    {
158      addr = &dummy;
159      return find_stack_direction ();
160    }
161  else
162    return (&dummy > addr) ? 1 : -1;
163}
164main ()
165{
166  exit (find_stack_direction() < 0);
167}],
168  ac_cv_c_stack_direction=1,
169  ac_cv_c_stack_direction=-1,
170  ac_cv_c_stack_direction=0)])
171AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction,
172  [Define if you know the direction of stack growth for your system;
173   otherwise it will be automatically deduced at run-time.
174        STACK_DIRECTION > 0 => grows toward higher addresses
175        STACK_DIRECTION < 0 => grows toward lower addresses
176        STACK_DIRECTION = 0 => direction of growth unknown])
177])
178