libiberty/aclocal.m4

   1 sinclude(../config/acx.m4)
   2 sinclude(../config/no-executables.m4)
   3 sinclude(../config/override.m4)
   4 sinclude(../config/picflag.m4)
   5 sinclude(../config/warnings.m4)
   6
   7 dnl See whether strncmp reads past the end of its string parameters.
   8 dnl On some versions of SunOS4 at least, strncmp reads a word at a time
   9 dnl but erroneously reads past the end of strings.  This can cause
  10 dnl a SEGV in some cases.
  11 AC_DEFUN(libiberty_AC_FUNC_STRNCMP,
  12 [AC_REQUIRE([AC_FUNC_MMAP])
  13 AC_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
  44 main ()
  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)
  76 rm -f core core.* *.core])
  77 if test $ac_cv_func_strncmp_works = no ; then
  78   AC_LIBOBJ([strncmp])
  79 fi
  80 ])
  81
  82 dnl See if errno must be declared even when <errno.h> is included.
  83 AC_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;],
  88 libiberty_cv_declare_errno=no,
  89 libiberty_cv_declare_errno=yes)])
  90 if test $libiberty_cv_declare_errno = yes
  91 then AC_DEFINE(NEED_DECLARATION_ERRNO, 1,
  92   [Define if errno must be declared even when <errno.h> is included.])
  93 fi
  94 ])
  95
  96 dnl See whether we need a declaration for a function.
  97 AC_DEFUN(libiberty_NEED_DECLARATION,
  98 [AC_MSG_CHECKING([whether $1 must be declared])
  99 AC_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],
 117 libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)])
 118 AC_MSG_RESULT($libiberty_cv_decl_needed_$1)
 119 if test $libiberty_cv_decl_needed_$1 = yes; then
 120   AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
 121             [Define if $1 is not declared in system header files.])
 122 fi
 123 ])dnl
 124
 125 # We always want a C version of alloca() compiled into libiberty,
 126 # because native-compiler support for the real alloca is so !@#$%
 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.
 130 AC_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)
 134 webecray
 135 #else
 136 wenotbecray
 137 #endif
 138 ], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
 139 if 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
 147 fi
 148
 149 AC_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 }
 162 main ()
 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)])
 169 AC_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 ])