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  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest.$ac_objext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_func_rand48=yes
else
  echo "$as_me: failed program was:" >&5
sed 's/^/| /' conftest.$ac_ext >&5

ac_cv_func_rand48=no
fi
rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
  ac_ext=c
ac_cpp='$CPP $CPPFLAGS'
ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
ac_compiler_gnu=$ac_cv_c_compiler_gnu

fi
echo "$as_me:$LINENO: result: $ac_cv_func_rand48" >&5
echo "${ECHO_T}$ac_cv_func_rand48" >&6

if test "$ac_cv_func_rand48" = "yes" ; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_RAND48 1
_ACEOF

fi
# The Ultrix 4.2 mips builtin alloca declared by alloca.h only works
# for constant arguments.  Useless!
echo "$as_me:$LINENO: checking for working alloca.h" >&5
echo $ECHO_N "checking for working alloca.h... $ECHO_C" >&6
if test "${ac_cv_working_alloca_h+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
#include <alloca.h>
int
main ()
{
char *p = (char *) alloca (2 * sizeof (int));
  ;
  return 0;
}
_ACEOF
rm -f conftest.$ac_objext conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_working_alloca_h=yes
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext \
      conftest$ac_exeext conftest.$ac_ext
fi
echo "$as_me:$LINENO: result: $ac_cv_working_alloca_h" >&5
echo "${ECHO_T}$ac_cv_working_alloca_h" >&6
if test $ac_cv_working_alloca_h = yes; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_ALLOCA_H 1
_ACEOF

fi

echo "$as_me:$LINENO: checking for alloca" >&5
echo $ECHO_N "checking for alloca... $ECHO_C" >&6
if test "${ac_cv_func_alloca_works+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
#ifdef __GNUC__
# define alloca __builtin_alloca
#else
# ifdef _MSC_VER
#  include <malloc.h>
#  define alloca _alloca
# else
#  if HAVE_ALLOCA_H
#   include <alloca.h>
#  else
#   ifdef _AIX
 #pragma alloca
#   else
#    ifndef alloca /* predefined by HP cc +Olibcalls */
char *alloca ();
#    endif
#   endif
#  endif
# endif
#endif

int
main ()
{
char *p = (char *) alloca (1);
  ;
  return 0;
}
_ACEOF
rm -f conftest.$ac_objext conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_func_alloca_works=yes
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext \
      conftest$ac_exeext conftest.$ac_ext
fi
echo "$as_me:$LINENO: result: $ac_cv_func_alloca_works" >&5
echo "${ECHO_T}$ac_cv_func_alloca_works" >&6

if test $ac_cv_func_alloca_works = yes; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_ALLOCA 1
_ACEOF

else
  # The SVR3 libPW and SVR4 libucb both contain incompatible functions
# that cause trouble.  Some versions do not even contain alloca or
# contain a buggy version.  If you still want to use their alloca,
# use ar to extract alloca.o from them instead of compiling alloca.c.

ALLOCA=alloca.$ac_objext

cat >>confdefs.h <<\_ACEOF
#define C_ALLOCA 1
_ACEOF


echo "$as_me:$LINENO: checking whether \`alloca.c' needs Cray hooks" >&5
echo $ECHO_N "checking whether \`alloca.c' needs Cray hooks... $ECHO_C" >&6
if test "${ac_cv_os_cray+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
#if defined(CRAY) && ! defined(CRAY2)
webecray
#else
wenotbecray
#endif

_ACEOF
if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
  $EGREP "webecray" >/dev/null 2>&1; then
  ac_cv_os_cray=yes
else
  ac_cv_os_cray=no
fi
rm -f conftest*

fi
echo "$as_me:$LINENO: result: $ac_cv_os_cray" >&5
echo "${ECHO_T}$ac_cv_os_cray" >&6
if test $ac_cv_os_cray = yes; then
  for ac_func in _getb67 GETB67 getb67; do
    as_ac_var=`echo "ac_cv_func_$ac_func" | $as_tr_sh`
echo "$as_me:$LINENO: checking for $ac_func" >&5
echo $ECHO_N "checking for $ac_func... $ECHO_C" >&6
if eval "test \"\${$as_ac_var+set}\" = set"; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
#define $ac_func innocuous_$ac_func

/* System header to define __stub macros and hopefully few prototypes,
    which can conflict with char $ac_func (); below.
    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
    <limits.h> exists even on freestanding compilers.  */
#ifdef __STDC__
# 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 $ac_func ();
/* The GNU C library defines this for functions which it implements
    to always fail with ENOSYS.  Some functions are actually named
    something starting with __ and the normal name is an alias.  */
#if defined (__stub_$ac_func) || defined (__stub___$ac_func)
choke me
#else
char (*f) () = $ac_func;
#endif
#ifdef __cplusplus
}
  ;
  return 0;
}
_ACEOF
rm -f conftest.$ac_objext conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  eval "$as_ac_var=yes"
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext \
      conftest$ac_exeext conftest.$ac_ext
fi
echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_var'}'`" >&5
echo "${ECHO_T}`eval echo '${'$as_ac_var'}'`" >&6
if test `eval echo '${'$as_ac_var'}'` = yes; then

cat >>confdefs.h <<_ACEOF
#define CRAY_STACKSEG_END $ac_func
_ACEOF

    break
fi

  done
fi

echo "$as_me:$LINENO: checking stack direction for C alloca" >&5
echo $ECHO_N "checking stack direction for C alloca... $ECHO_C" >&6
if test "${ac_cv_c_stack_direction+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  if test "$cross_compiling" = yes; then
  ac_cv_c_stack_direction=0
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
int
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;
}

int
main ()
{
  exit (find_stack_direction () < 0);
}
_ACEOF
rm -f conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  (eval $ac_link) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_c_stack_direction=1
else
  echo "$as_me: program exited with status $ac_status" >&5
echo "$as_me: failed program was:" >&5
( exit $ac_status )
ac_cv_c_stack_direction=-1
fi
rm -f core *.core gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
fi
fi
echo "$as_me:$LINENO: result: $ac_cv_c_stack_direction" >&5
echo "${ECHO_T}$ac_cv_c_stack_direction" >&6

cat >>confdefs.h <<_ACEOF
#define STACK_DIRECTION $ac_cv_c_stack_direction
_ACEOF


fi



for ac_header in stdlib.h unistd.h
do
as_ac_Header=`echo "ac_cv_header_$ac_header" | $as_tr_sh`
if eval "test \"\${$as_ac_Header+set}\" = set"; then
  echo "$as_me:$LINENO: checking for $ac_header" >&5
echo $ECHO_N "checking for $ac_header... $ECHO_C" >&6
if eval "test \"\${$as_ac_Header+set}\" = set"; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
fi
echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_Header'}'`" >&5
echo "${ECHO_T}`eval echo '${'$as_ac_Header'}'`" >&6
else
  # Is the header compilable?
echo "$as_me:$LINENO: checking $ac_header usability" >&5
echo $ECHO_N "checking $ac_header usability... $ECHO_C" >&6
cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
$ac_includes_default
#include <$ac_header>
_ACEOF
rm -f conftest.$ac_objext
if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest.$ac_objext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_header_compiler=yes
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
echo "$as_me:$LINENO: result: $ac_header_compiler" >&5
echo "${ECHO_T}$ac_header_compiler" >&6

# Is the header present?
echo "$as_me:$LINENO: checking $ac_header presence" >&5
echo $ECHO_N "checking $ac_header presence... $ECHO_C" >&6
cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
#include <$ac_header>
_ACEOF
if { (eval echo "$as_me:$LINENO: \"$ac_cpp conftest.$ac_ext\"") >&5
  (eval $ac_cpp conftest.$ac_ext) 2>conftest.er1
  ac_status=$?
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } >/dev/null; then
  if test -s conftest.err; then
    ac_cpp_err=$ac_c_preproc_warn_flag
    ac_cpp_err=$ac_cpp_err$ac_c_werror_flag
  else
    ac_cpp_err=
  fi
else
  ac_cpp_err=yes
fi
if test -z "$ac_cpp_err"; then
  ac_header_preproc=yes
else
  echo "$as_me: failed program was:" >&5
  ac_header_preproc=no
fi
rm -f conftest.err conftest.$ac_ext
echo "$as_me:$LINENO: result: $ac_header_preproc" >&5
echo "${ECHO_T}$ac_header_preproc" >&6

# So?  What about this header?
case $ac_header_compiler:$ac_header_preproc:$ac_c_preproc_warn_flag in
  yes:no: )
    { echo "$as_me:$LINENO: WARNING: $ac_header: accepted by the compiler, rejected by the preprocessor!" >&5
echo "$as_me: WARNING: $ac_header: accepted by the compiler, rejected by the preprocessor!" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header: proceeding with the compiler's result" >&5
echo "$as_me: WARNING: $ac_header: proceeding with the compiler's result" >&2;}
    ac_header_preproc=yes
    { echo "$as_me:$LINENO: WARNING: $ac_header: present but cannot be compiled" >&5
echo "$as_me: WARNING: $ac_header: present but cannot be compiled" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header:     check for missing prerequisite headers?" >&5
echo "$as_me: WARNING: $ac_header:     check for missing prerequisite headers?" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header: see the Autoconf documentation" >&5
echo "$as_me: WARNING: $ac_header: see the Autoconf documentation" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header:     section \"Present But Cannot Be Compiled\"" >&5
echo "$as_me: WARNING: $ac_header:     section \"Present But Cannot Be Compiled\"" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header: proceeding with the preprocessor's result" >&5
echo "$as_me: WARNING: $ac_header: proceeding with the preprocessor's result" >&2;}
    { echo "$as_me:$LINENO: WARNING: $ac_header: in the future, the compiler will take precedence" >&5
echo "$as_me: WARNING: $ac_header: in the future, the compiler will take precedence" >&2;}
## ----------------------------------- ##
## Report this to llvmbugs@cs.uiuc.edu ##
## ----------------------------------- ##
esac
echo "$as_me:$LINENO: checking for $ac_header" >&5
echo $ECHO_N "checking for $ac_header... $ECHO_C" >&6
if eval "test \"\${$as_ac_Header+set}\" = set"; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  eval "$as_ac_Header=\$ac_header_preproc"
fi
echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_Header'}'`" >&5
echo "${ECHO_T}`eval echo '${'$as_ac_Header'}'`" >&6

fi
if test `eval echo '${'$as_ac_Header'}'` = yes; then
  cat >>confdefs.h <<_ACEOF
#define `echo "HAVE_$ac_header" | $as_tr_cpp` 1
_ACEOF

fi

done


for ac_func in getpagesize
do
as_ac_var=`echo "ac_cv_func_$ac_func" | $as_tr_sh`
echo "$as_me:$LINENO: checking for $ac_func" >&5
echo $ECHO_N "checking for $ac_func... $ECHO_C" >&6
if eval "test \"\${$as_ac_var+set}\" = set"; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
#define $ac_func innocuous_$ac_func

/* System header to define __stub macros and hopefully few prototypes,
    which can conflict with char $ac_func (); below.
    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
    <limits.h> exists even on freestanding compilers.  */
#ifdef __STDC__
# 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 $ac_func ();
/* The GNU C library defines this for functions which it implements
    to always fail with ENOSYS.  Some functions are actually named
    something starting with __ and the normal name is an alias.  */
#if defined (__stub_$ac_func) || defined (__stub___$ac_func)
choke me
#else
char (*f) () = $ac_func;
#endif
#ifdef __cplusplus
}
  ;
  return 0;
}
_ACEOF
rm -f conftest.$ac_objext conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  eval "$as_ac_var=yes"
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext \
      conftest$ac_exeext conftest.$ac_ext
fi
echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_var'}'`" >&5
echo "${ECHO_T}`eval echo '${'$as_ac_var'}'`" >&6
if test `eval echo '${'$as_ac_var'}'` = yes; then
  cat >>confdefs.h <<_ACEOF
#define `echo "HAVE_$ac_func" | $as_tr_cpp` 1
_ACEOF

fi
done

echo "$as_me:$LINENO: checking for working mmap" >&5
echo $ECHO_N "checking for working mmap... $ECHO_C" >&6
if test "${ac_cv_func_mmap_fixed_mapped+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  if test "$cross_compiling" = yes; then
  ac_cv_func_mmap_fixed_mapped=no
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
$ac_includes_default
/* malloc might have been renamed as rpl_malloc. */
#undef malloc

/* Thanks to Mike Haertel and Jim Avera for this test.
   Here is a matrix of mmap possibilities:
	mmap private not fixed
	mmap private fixed at somewhere currently unmapped
	mmap private fixed at somewhere already mapped
	mmap shared not fixed
	mmap shared fixed at somewhere currently unmapped
	mmap shared fixed at somewhere already mapped
   For private mappings, we should verify that changes cannot be read()
   back from the file, nor mmap's back from the file at a different
   address.  (There have been systems where private was not correctly
   implemented like the infamous i386 svr4.0, and systems where the
   VM page cache was not coherent with the file system buffer cache
   like early versions of FreeBSD and possibly contemporary NetBSD.)
   For shared mappings, we should conversely verify that changes get
   propagated back to all the places they're supposed to be.

   Grep wants private fixed already mapped.
   The main things grep needs to know about mmap are:
   * does it exist and is it safe to write into the mmap'd area
   * how to use it (BSD variants)  */

#include <fcntl.h>
#include <sys/mman.h>

#if !STDC_HEADERS && !HAVE_STDLIB_H
char *malloc ();
#endif

/* This mess was copied from the GNU getpagesize.h.  */
#if !HAVE_GETPAGESIZE
/* Assume that all systems that can run configure have sys/param.h.  */
# if !HAVE_SYS_PARAM_H
#  define HAVE_SYS_PARAM_H 1
# endif

# ifdef _SC_PAGESIZE
#  define getpagesize() sysconf(_SC_PAGESIZE)
# else /* no _SC_PAGESIZE */
#  if HAVE_SYS_PARAM_H
#   include <sys/param.h>
#   ifdef EXEC_PAGESIZE
#    define getpagesize() EXEC_PAGESIZE
#   else /* no EXEC_PAGESIZE */
#    ifdef NBPG
#     define getpagesize() NBPG * CLSIZE
#     ifndef CLSIZE
#      define CLSIZE 1
#     endif /* no CLSIZE */
#    else /* no NBPG */
#     ifdef NBPC
#      define getpagesize() NBPC
#     else /* no NBPC */
#      ifdef PAGESIZE
#       define getpagesize() PAGESIZE
#      endif /* PAGESIZE */
#     endif /* no NBPC */
#    endif /* no NBPG */
#   endif /* no EXEC_PAGESIZE */
#  else /* no HAVE_SYS_PARAM_H */
#   define getpagesize() 8192	/* punt totally */
#  endif /* no HAVE_SYS_PARAM_H */
# endif /* no _SC_PAGESIZE */

#endif /* no HAVE_GETPAGESIZE */

int
main ()
{
  char *data, *data2, *data3;
  int i, pagesize;
  int fd;

  pagesize = getpagesize ();

  /* First, make a file with some known garbage in it. */
  data = (char *) malloc (pagesize);
  if (!data)
    exit (1);
  for (i = 0; i < pagesize; ++i)
    *(data + i) = rand ();
  umask (0);
  fd = creat ("conftest.mmap", 0600);
  if (fd < 0)
    exit (1);
  if (write (fd, data, pagesize) != pagesize)
    exit (1);
  close (fd);

  /* Next, try to mmap the file at a fixed address which already has
     something else allocated at it.  If we can, also make sure that
     we see the same garbage.  */
  fd = open ("conftest.mmap", O_RDWR);
  if (fd < 0)
    exit (1);
  data2 = (char *) malloc (2 * pagesize);
  if (!data2)
    exit (1);
  data2 += (pagesize - ((long) data2 & (pagesize - 1))) & (pagesize - 1);
  if (data2 != mmap (data2, pagesize, PROT_READ | PROT_WRITE,
    exit (1);
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data2 + i))
      exit (1);

  /* Finally, make sure that changes to the mapped area do not
     percolate back to the file as seen by read().  (This is a bug on
     some variants of i386 svr4.0.)  */
  for (i = 0; i < pagesize; ++i)
    *(data2 + i) = *(data2 + i) + 1;
  data3 = (char *) malloc (pagesize);
  if (!data3)
    exit (1);
  if (read (fd, data3, pagesize) != pagesize)
    exit (1);
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data3 + i))
      exit (1);
  close (fd);
  exit (0);
}
_ACEOF
rm -f conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  (eval $ac_link) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_func_mmap_fixed_mapped=yes
else
  echo "$as_me: program exited with status $ac_status" >&5
echo "$as_me: failed program was:" >&5
( exit $ac_status )
ac_cv_func_mmap_fixed_mapped=no
fi
rm -f core *.core gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
fi
fi
echo "$as_me:$LINENO: result: $ac_cv_func_mmap_fixed_mapped" >&5
echo "${ECHO_T}$ac_cv_func_mmap_fixed_mapped" >&6
if test $ac_cv_func_mmap_fixed_mapped = yes; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_MMAP 1
_ACEOF

fi
rm -f conftest.mmap

if test "$ac_cv_func_mmap_fixed_mapped" = "no"
then
	{ echo "$as_me:$LINENO: WARNING: mmap() required but not found" >&5
echo "$as_me: WARNING: mmap() required but not found" >&2;}
echo "$as_me:$LINENO: checking for mmap of files" >&5
echo $ECHO_N "checking for mmap of files... $ECHO_C" >&6
if test "${ac_cv_func_mmap_file+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
ac_cpp='$CPP $CPPFLAGS'
ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
ac_compiler_gnu=$ac_cv_c_compiler_gnu

  if test "$cross_compiling" = yes; then
    /* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
  fd = creat ("foo",0777);
  fd = (int) mmap (0, 1, PROT_READ, MAP_SHARED, fd, 0);
  unlink ("foo");
_ACEOF
rm -f conftest$ac_exeext
if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
  (eval $ac_link) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_func_mmap_file=yes
else
  echo "$as_me: program exited with status $ac_status" >&5
echo "$as_me: failed program was:" >&5
( exit $ac_status )
ac_cv_func_mmap_file=no
fi
rm -f core *.core gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
fi
  ac_ext=c
ac_cpp='$CPP $CPPFLAGS'
ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
ac_compiler_gnu=$ac_cv_c_compiler_gnu


fi
echo "$as_me:$LINENO: result: $ac_cv_func_mmap_file" >&5
echo "${ECHO_T}$ac_cv_func_mmap_file" >&6
if test "$ac_cv_func_mmap_file" = yes; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_MMAP_FILE
if test "$ac_cv_func_mmap_file" = "no"
	{ echo "$as_me:$LINENO: WARNING: mmap() of files required but not found" >&5
echo "$as_me: WARNING: mmap() of files required but not found" >&2;}
fi
echo "$as_me:$LINENO: checking for MAP_ANONYMOUS vs. MAP_ANON" >&5
echo $ECHO_N "checking for MAP_ANONYMOUS vs. MAP_ANON... $ECHO_C" >&6
if test "${ac_cv_header_mmap_anon+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
ac_cpp='$CPP $CPPFLAGS'
ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
ac_compiler_gnu=$ac_cv_c_compiler_gnu

  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF
/* end confdefs.h.  */
int
main ()
{
mmap (0, 1, PROT_READ, MAP_ANONYMOUS, -1, 0); return (0);
  ;
  return 0;
}
_ACEOF
rm -f conftest.$ac_objext
if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
  grep -v '^ *+' conftest.er1 >conftest.err
  rm -f conftest.er1
  cat conftest.err >&5
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); } &&
	 { ac_try='test -z "$ac_c_werror_flag"
			 || test ! -s conftest.err'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; } &&
	 { ac_try='test -s conftest.$ac_objext'
  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
  (eval $ac_try) 2>&5
  ac_status=$?
  echo "$as_me:$LINENO: \$? = $ac_status" >&5
  (exit $ac_status); }; }; then
  ac_cv_header_mmap_anon=yes
else
  echo "$as_me: failed program was:" >&5
rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
  ac_ext=c
ac_cpp='$CPP $CPPFLAGS'
ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
ac_compiler_gnu=$ac_cv_c_compiler_gnu


fi
echo "$as_me:$LINENO: result: $ac_cv_header_mmap_anon" >&5
echo "${ECHO_T}$ac_cv_header_mmap_anon" >&6
if test "$ac_cv_header_mmap_anon" = yes; then

cat >>confdefs.h <<\_ACEOF
#define HAVE_MMAP_ANONYMOUS
_ACEOF

fi

echo "$as_me:$LINENO: checking return type of signal handlers" >&5
echo $ECHO_N "checking return type of signal handlers... $ECHO_C" >&6
if test "${ac_cv_type_signal+set}" = set; then
  echo $ECHO_N "(cached) $ECHO_C" >&6
else
  cat >conftest.$ac_ext <<_ACEOF
/* confdefs.h.  */
_ACEOF
cat confdefs.h >>conftest.$ac_ext
cat >>conftest.$ac_ext <<_ACEOF