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