configure.in

#/*************************************************************************
#** Written by Thomas Richter (THOR Software)                            **
#** Sponsored by Accusoft, Tampa, FL and				 **
#** the Computing Center of the University of Stuttgart                  **
#**									 **
#** See README.license for license conditions				 **
#**************************************************************************
#
#This software is a complete implementation of ITU T.81 - ISO/IEC 10918,
#also known as JPEG. It implements the standard in all its variations,
#including lossless coding, hierarchical coding, arithmetic coding and
#DNL, restart markers and 12bpp coding.
#
#In addition, it includes support for new proposed JPEG technologies that
#are currently under discussion in the SC29/WG1 standardization group of
#the ISO (also known as JPEG). These technologies include lossless coding
#of JPEG backwards compatible to the DCT process, and various other
#extensions.
#
#The author is a long-term member of the JPEG committee and it is hoped that
#this implementation will trigger and facilitate the future development of
#the JPEG standard, both for private use, industrial applications and within
#the committee itself.
#
#  Copyright (C) 2011-2012 Accusoft, Thomas Richter <thor@math.tu-berlin.de>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
#***********************************************************************************
#** Configuration script for the jpeg project,
#** THOR Software, Thomas Richter
#**
#** $Id: configure.in,v 1.16 2022/03/07 15:54:33 thor Exp $
#**
#** In this module: autoconf script for libjpeg
#**********************************************************************************/
#
# Process this file with autoconf to produce a configure script.
AC_INIT(jpeg,thomas.richter@iis.fraunhofer.de)
AC_CONFIG_SRCDIR([config.h])
AC_CONFIG_HEADER([autoconfig.h])
AC_PREFIX_DEFAULT([$HOME/bin/wavelet])
#
#
CFLAGS="$machine_option $CFLAGS"
CXXFLAGS="$machine_option $CXXFLAGS"
LDFLAGS="$machine_option $LDFLAGS"
#
AC_SUBST(BITSIZE,${machine_option})
#
# Checks for programs.
AC_PROG_CXX([g++-4.9 g++-4.7 g++-4.4 g++-4.3 g++-4.2 g++-4.1 g++-4.0 g++-3.4 g++-3.3 g++-3.2 g++ clang++ icc c++ gpp cxx cc++])
AC_PROG_CC([gcc-4.9 gcc-4.7 gcc-4.4 gcc-4.3 gcc-4.2 gcc-4.1 gcc-4.0 gcc-3.4 gcc-3.3 gcc-3.2 gcc clang icc cc])
AC_PROG_CC_STDC
AC_C_BIGENDIAN([AC_DEFINE(JPG_BIG_ENDIAN,[1],[Define to 1 for big endian])],[AC_DEFINE(JPG_LIL_ENDIAN,[1],[Define to 1 for little endian])])
#
# Set some compiler specific macros, dependent on whether we have a GNU C
# or a generic compiler
if test "$ac_compiler_gnu" = "yes"; then
# Define a couple of options concerning the compiler
  ac_cccmd=`echo ${CC} | cut -f 1 -d ' ' | cut -f 1 -d '-'`
  if test "$ac_cccmd" = "icpc"; then
     ac_cccmd="icc"
  fi
  AC_SUBST(SETTINGS,${ac_cccmd})
else
  ac_cccmd=`echo ${CXX} | cut -f 1 -d ' '`
  AC_SUBST(SETTINGS,${ac_cccmd})
fi
AC_SUBST(COMPILER,${CXX})
AC_SUBST(CC_ONLY,${CC})
#
# The following is a workaround for an autoconf expanding
# $prefix too late.
if test "$prefix" = "NONE"; then
   AC_SUBST(PREFIX,${ac_default_prefix})
else
   AC_SUBST(PREFIX,${prefix})
fi
#
# We first check in the C language as autoconf seems to expect that
# the compiler accepts conflicting prototypes. Wierd.
AC_LANG(C)

#
# Check whether the compiler supports -march. If not, try whether it supports
# -mcpu.
if test "$cputype_option" != ""; then
   ac_SAVE_CFLAGS="$CFLAGS"
   ac_SAVE_LDFLAGS="$LDFLAGS"
   ac_SAVE_CXXFLAGS="$CXXFLAGS"
   AC_MSG_CHECKING([whether the compiler supports -march])
   #
   CFLAGS="-march=$cputype_option $CFLAGS"
   AC_TRY_COMPILE([],[],[ac_have_march='yes';AC_SUBST(CPU,"-march=$cputype_option")],
	[ac_have_march='no'])
   AC_MSG_RESULT($ac_have_march)
   #
   CFLAGS="$ac_SAVE_CFLAGS"
   LDFLAGS="$ac_SAVE_LDFLAGS"
   CXXFLAGS="$ac_SAVE_CXXFLAGS"
   #
   if test "$ac_have_march" = "yes"; then
      CFLAGS="-march=$cputype_option $CFLAGS"
      CXXFLAGS="-march=$cputype_option $CXXFLAGS"
      LDFLAGS="-march=$cputype_option $LDFLAGS"
   else
      AC_MSG_CHECKING([whether the compiler supports -mcpu])
      #
      CFLAGS="-mcpu=$cputype_option $CFLAGS"
      AC_TRY_COMPILE([],[],[ac_have_mcpu='yes';AC_SUBST(CPU,"-mcpu=$cputype_option")],
	[ac_have_mcpu='no'])
      AC_MSG_RESULT($ac_have_mcpu)
      #
      CFLAGS="$ac_SAVE_CFLAGS"
      LDFLAGS="$ac_SAVE_LDFLAGS"
      CXXFLAGS="$ac_SAVE_CXXFLAGS"
      #
      if test "$ac_have_mcpu" = "yes"; then
      	 CFLAGS="-mcpu=$cputype_option $CFLAGS"
      	 CXXFLAGS="-mcpu=$cputype_option $CXXFLAGS"
      	 LDFLAGS="-mcpu=$cputype_option $LDFLAGS"
      else
         AC_SUBST(CPU,"")
      fi	 
   fi
else
   AC_SUBST(CPU,"")
fi
#
# Enable CPU tune
if test "$tunetype_option" != ""; then
   ac_SAVE_CFLAGS="$CFLAGS"
   ac_SAVE_LDFLAGS="$LDFLAGS"
   ac_SAVE_CXXFLAGS="$CXXFLAGS"
   AC_MSG_CHECKING([whether the compiler supports -mtune])
   #
   CFLAGS="-mtune=$tunetype_option $CFLAGS"
   AC_TRY_COMPILE([],[],[ac_have_mtune='yes';AC_SUBST(TUNE,"-mtune=$tunetype_option")],
	[ac_have_mtune='no'])
   AC_MSG_RESULT($ac_have_mtune)
   #
   CFLAGS="$ac_SAVE_CFLAGS"
   LDFLAGS="$ac_SAVE_LDFLAGS"
   CXXFLAGS="$ac_SAVE_CXXFLAGS"
   #
   if test "$ac_have_mtune" = "yes"; then
      CFLAGS="-mtune=$tunetype_option $CFLAGS"
      CXXFLAGS="-mtune=$tunetype_option $CXXFLAGS"
      LDFLAGS="-mtune=$tunetype_option $LDFLAGS"
   else
      AC_SUBST(TUNE,"")
   fi
else
   AC_SUBST(TUNE,"")
fi
#
# Check compiler features. We need long long and unsigned long long
AC_CHECK_TYPES([long long])
AC_CHECK_TYPES([unsigned long long])
AC_CHECK_TYPES([__int64])
if test "$ac_cv_type___int64" = "no"; then
 if test "$ac_cv_type_long_long" = "no"; then
  AC_MSG_ERROR([your compiler must support a signed 64 bit data type. jpeg cannot be build without it.])
 fi
 if test "$ac_cv_type_unsigned_long_long" = "no"; then
  AC_MSG_ERROR([your compiler must support an unsigned 64 bit data type. jpeg cannot be build without it.])
 fi
fi
#
# Get type sizes
AC_CHECK_SIZEOF([char])
AC_CHECK_SIZEOF([short])
AC_CHECK_SIZEOF([int])
AC_CHECK_SIZEOF([long])
AC_CHECK_SIZEOF([long long])
AC_CHECK_SIZEOF([__int64])
AC_CHECK_SIZEOF([void *])
#
#
# Checks for header files.
AC_HEADER_STDC

# Checks for typedefs, structures, and compiler characteristics.
AC_C_CONST
AC_C_INLINE
AC_TYPE_SIZE_T
AC_HEADER_TIME
AC_HEADER_STAT
AC_CHECK_HEADERS([fcntl.h stdlib.h string.h strings.h signal.h unistd.h stdarg.h errno.h stdio.h])
AC_CHECK_HEADERS([bstring.h bstrings.h ctype.h setjmp.h stddef.h])
AC_CHECK_HEADERS([time.h sys/time.h sys/times.h sys/param.h assert.h math.h netinet/in.h])
AC_CHECK_HEADERS([stdint.h],[ac_have_stdint_h='yes'],[ac_have_stdint_h='no'])
if test "$ac_have_stdint_h" = "yes"; then
   AC_CHECK_TYPE([int8_t],[AC_DEFINE(HAS_INT8_T,[1],[Define to 1 if the C99 type int8_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([int16_t],[AC_DEFINE(HAS_INT16_T,[1],[Define to 1 if the C99 type int16_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([int32_t],[AC_DEFINE(HAS_INT32_T,[1],[Define to 1 if the C99 type int32_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([int64_t],[AC_DEFINE(HAS_INT64_T,[1],[Define to 1 if the C99 type int64_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([uint8_t],[AC_DEFINE(HAS_UINT8_T,[1],[Define to 1 if the C99 type uint8_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([uint16_t],[AC_DEFINE(HAS_UINT16_T,[1],[Define to 1 if the C99 type uint16_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([uint32_t],[AC_DEFINE(HAS_UINT32_T,[1],[Define to 1 if the C99 type uint32_t is available])],[],[#include<stdint.h>])
   AC_CHECK_TYPE([uint64_t],[AC_DEFINE(HAS_UINT64_T,[1],[Define to 1 if the C99 type uint64_t is available])],[],[#include<stdint.h>])
fi
#
#
# Checks for library functions.
AC_FUNC_ERROR_AT_LINE
AC_PROG_GCC_TRADITIONAL
#
#
# A GNU compliant malloc is not available on AIX, but isn't needed
# in first place....
# AC_FUNC_MALLOC
AC_FUNC_MEMCMP
AC_TYPE_SIGNAL
AC_FUNC_VPRINTF
AC_CHECK_FUNCS([gettimeofday memchr memmove memset strchr strerror strrchr strtol strtod])
AC_CHECK_FUNCS([time snprintf vsnprintf clock gettimeofday])
AC_CHECK_FUNCS([isspace longjmp malloc free])
AC_CHECK_FUNCS([open close read write lseek rename signal sleep])
AC_CHECK_FUNCS([fopen64])
#
# Test whether builtin functions are available.
CFLAGS_KEEP="${CFLAGS}"
CFLAGS="${CFLAGS} -Werror"
#
AC_MSG_CHECKING([for __builtin_memset])
AC_TRY_COMPILE([],[
void *s;
__builtin_memset(&s,0,sizeof(s));
],[ac_have_builtin_memset='yes';AC_DEFINE(HAVE_BUILTIN_MEMSET,[1],[Define to 1 if __builtin_memset is available])],[ac_have_builtin_memset='no'])
AC_MSG_RESULT($ac_have_builtin_memset)
#
AC_MSG_CHECKING([for __builtin_memcpy])
AC_TRY_COMPILE([],[
void *s;
void *t;
__builtin_memcpy(&s,&t,sizeof(s));
],[ac_have_builtin_memcpy='yes';AC_DEFINE(HAVE_BUILTIN_MEMCPY,[1],[Define to 1 if __builtin_memcpy is available])],[ac_have_builtin_memcpy='no'])
AC_MSG_RESULT($ac_have_builtin_memcpy)
#
AC_MSG_CHECKING([for __builtin_memmove])
AC_TRY_COMPILE([],[
void *s;
void *t;
__builtin_memmove(&s,&t,sizeof(s));
],[ac_have_builtin_memmove='yes';AC_DEFINE(HAVE_BUILTIN_MEMMOVE,[1],[Define to 1 if __builtin_memmove is available])],[ac_have_builtin_memmove='no'])
AC_MSG_RESULT($ac_have_builtin_memmove)
#
AC_MSG_CHECKING([for __builtin_expect])
AC_TRY_COMPILE([],[
int s = 1;
int t = 2;
if (__builtin_expect(s != t,1))
   t++;
],[ac_have_builtin_expect='yes';AC_DEFINE(HAVE_BUILTIN_EXPECT,[1],[Define to 1 if __builtin_expect is available])],[ac_have_builtin_expect='no'])
AC_MSG_RESULT($ac_have_builtin_expect)
#
CFLAGS="${CFLAGS_KEEP}"
#
# Check whether the compiler supports -Wimplicit-fallthrough=1 as option. This helps to avoid some
# pointless warnings on the later gcc versions.
#
AC_MSG_CHECKING([for the -Wimplicit-fallthrough compiler switch])
CFLAGS="-Wimplicit-fallthrough=1 $save_CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_implicit_fallthrough='yes';AC_SUBST(WARN_OPTS,"-Wimplicit-fallthrough=1")],[ac_have_implicit_fallthrough='no';AC_SUBST(WARN_OPTS,"")])
AC_MSG_RESULT($ac_have_implicit_fallthrough)
#
# Check whether the compiler supports -Wno-class-memaccess as option. This allows mem-setting
# entire classes to zero.
#
save_CXXFLAGS="$CXXFLAGS"
AC_LANG(C++)
AC_MSG_CHECKING([for the -Wno-class-memaccess compiler switch])
CXXFLAGS="-Werror -Wno-class-memaccess $save_CXXFLAGS"
AC_TRY_COMPILE([],[],[ac_have_no_class_memaccess='yes';AC_SUBST(WARN_MEM_OPTS,"-Wno-class-memaccess")],[ac_have_no_class_memaccess='no';AC_SUBST(WARN_MEM_OPTS,"")])
AC_MSG_RESULT($ac_have_no_class_memaccess)
CXXFLAGS="$save_CXXFLAGS"
AC_LANG(C)
#
# Check whether we can turn off the deprecation warning of the register keyword.
AC_MSG_CHECKING([for the -Wno-deprecated-register compiler switch])
CFLAGS="-Werror -Wno-deprecated-register $save_CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_no_deprecated_register='yes';AC_SUBST(WARN_REG_OPTS,"-Wno-deprecated-register")],[ac_have_no_deprecated_register='no';AC_SUBST(WARN_REG_OPTS,"")])
AC_MSG_RESULT($ac_have_no_deprecated_register)
#
# Check whether we can generate position-independent code. This is sometimes required for
# library building
AC_MSG_CHECKING([for the -fPIC compiler switch])
CFLAGS="-fPIC $save_CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_fpic='yes';AC_SUBST(LIB_PICOPTS,"-fPIC")],[ac_have_fpic='no'])
AC_MSG_RESULT($ac_have_fpic)
#
# The test for llseek and lseek64 does not seem to work properly unless we try to compile...
# yuck!
AC_LANG(C++)
AC_MSG_CHECKING([for llseek])
AC_TRY_COMPILE([
#define _LARGEFILE64_SOURCE
#include<sys/types.h>
#include<unistd.h>
],[loff_t res = llseek(0,0,0);],
[ac_have_llseek='yes';AC_DEFINE(HAVE_LLSEEK,[1],[Define to 1 if llseek is available])],[ac_have_llseek='no'])
AC_MSG_RESULT($ac_have_llseek)
#
AC_MSG_CHECKING([for lseek64])
AC_TRY_COMPILE([
#define _LARGEFILE64_SOURCE
#include<sys/types.h>
#include<unistd.h>
],[off64_t res = lseek64(0,0,0);],
[ac_have_lseek64='yes';AC_DEFINE(HAVE_LSEEK64,[1],[Define to 1 if lseek64 is available])],[ac_have_lseek64='no'])
AC_MSG_RESULT($ac_have_lseek64)
AC_LANG(C)
#
# The following extras are only for the test sources
AC_CHECK_FUNCS([htonl htons ntohl ntohs])
AC_CHECK_FUNCS([signal sigaction sigemptyset pipe dup dup2 execve fork fstat system kill sleep])
#
AC_CHECK_TYPE([struct timeval],[AC_DEFINE(HAS_STRUCT_TIMEVAL,[1],[Define to 1 if struct timeval is available])])
AC_CHECK_TYPE([ptrdiff_t],[AC_DEFINE(HAS_PTRDIFF_T,[1],[Define to 1 if ptrdiff_t type is available])])
#
# Checks for extended timing methods
AC_CHECK_FUNCS([sysconf times])
AC_CHECK_TYPE([struct tms],[AC_DEFINE(HAS_STRUCT_TMS,[1],[Define to 1 if struct tms is available])],[],[#include<sys/times.h>])
AC_CHECK_DECL([_SC_CLK_TCK],[AC_DEFINE(HAS_SC_CLK_TCK,[1],[Define to 1 if _SC_CLK_TCK is available for sysconf])],[],[#include<unistd.h>])
AC_CHECK_DECL([CLK_TCK],[AC_DEFINE(HAS_CLK_TCK,[1],[Define to 1 if the variable CLK_TCK is available])],[],[#include<sys/time.h>])
AC_CHECK_DECL([HZ],[AC_DEFINE(HAS_HZ,[1],[Define to 1 if the variable HZ is available])],[],[#include<sys/param.h>])
#
# Checks for IO file descriptors
AC_CHECK_DECL([STDIN_FILENO],[AC_DEFINE(HAS_STDIN_FILENO,[1],[Define to 1 if the STDIN_FILENO define is available])],[],[#include<unistd.h>])
AC_CHECK_DECL([STDOUT_FILENO],[AC_DEFINE(HAS_STDOUT_FILENO,[1],[Define to 1 if the STDOUT_FILENO define is available])],[],[#include<unistd.h>])
AC_CHECK_DECL([STDERR_FILENO],[AC_DEFINE(HAS_STDERR_FILENO,[1],[Define to 1 if the STDERR_FILENO define is available])],[],[#include<unistd.h>])
#
# Checks for libraries
# These tests must go here as otherwise they break the standard header tests for
# reasons beyond me.
AC_SEARCH_LIBS([exp],[m])
#
# libgcc_s required for 64 bit arithmetic on 64 bit.
AC_CHECK_LIB(gcc_s,__muldc3,[AC_SUBST(LGCCS_OPTS,"-lgcc_s")],[AC_SUBST(LGCCS_OPTS,"")])
#
AC_SUBST(MALLOC_LIB,"")
#
#
# check for argument type for a signal handler: These tests have to run with a C++ compiler
AC_LANG(C++)
# The first test checks whether a signal handler takes an "int" as argument.
AC_MSG_CHECKING([whether argument type for signal handlers is "int"])
AC_TRY_COMPILE([extern "C"{
#include<signal.h>
}
RETSIGTYPE sh(int a) { } void si(void) { signal(SIGINT, sh);}],[],
[ac_arg_type_int='yes';AC_DEFINE(SIG_ARG_TYPE_INT,[1],[Define to 1 if required argument to signal handlers is int])],
[ac_arg_type_int='no'])
AC_MSG_RESULT($ac_arg_type_int)
#
# Ditto for ... instead
AC_MSG_CHECKING([whether argument type for signal handlers is "..."])
AC_TRY_COMPILE([
extern "C" {
#include<signal.h>
}
RETSIGTYPE sh(...) { } void si(void) { signal(SIGINT, sh);}],[],
[ac_arg_type_dots='yes';AC_DEFINE(SIG_ARG_TYPE_DOTS,[1],[Define to 1 if required argument to signal handlers is "..."])],
[ac_arg_type_dots='no'])
AC_MSG_RESULT($ac_arg_type_dots)
#
#
# Test whether we have the GNU __attribute__ extension
AC_MSG_CHECKING([whether the GNU __attribute__ extension is available])
AC_TRY_COMPILE([],[extern void test(const char *fmt,...) __attribute__ (( format(printf,1,2) ));],
[ac_has_attributes='yes';AC_DEFINE(HAS_ATTRIBUTES,[1],[Define to 1 if the GNU __attribute__ extension is available])],
[ac_has_attributes='no'])
AC_MSG_RESULT($ac_has_attributes)
#
#
# Check for the __null GNU provides. We try to use it if possible.
AC_MSG_CHECKING([for the __null keyword])
AC_TRY_COMPILE([],[int *n = __null;],[ac_has_null='yes';AC_DEFINE(HAS__NULL_TYPE,[1],[Define to 1 if the __null keyword is available])],[ac_has_null='no'])
AC_MSG_RESULT($ac_has_null)
#
# Check whether integers work as template arguments. This is required
# for several classes, but not all compilers accept it.
AC_MSG_CHECKING([whether integer constants are valid template arguments])
AC_TRY_COMPILE([
template<int a>
struct A {
 int b;
 A() : b(a) {}
};
],[A<1> a;],
[ac_int_template_args='yes';AC_DEFINE(HAS_INT_TEMPLATE_ARGS,[1],[Define to 1 if integer constants are valid template arguments])],
[ac_int_template_args='no'])
AC_MSG_RESULT($ac_int_template_args)
if test "$ac_int_template_args" = "no"; then
 AC_MSG_ERROR([your compiler must support constant integers as template arguments. jpeg cannot be build without it.])
fi
#
# Check for atomic increment and decrement instructions. These are not really
# needed except for the debugging code. Everything else is done much less
# compiler dependent with mutexes.
AC_MSG_CHECKING([for atomic arithmetic functions __sync_add_and_fetch and __sync_fetch_and_sub])
AC_TRY_COMPILE([],
[
 unsigned long v = 0;

 if (__sync_add_and_fetch(&v,1) != 1)
  return 10;
 if (__sync_fetch_and_sub(&v,1) != 1)
  return 10;
],
[ac_atomic_addsub='yes';AC_DEFINE(HAVE_ATOMIC_ADDSUB,[1],[Define to 1 if __sync arithmetic functions are available])],
[ac_atomic_addsub='no'])
AC_MSG_RESULT($ac_atomic_addsub)
#
# Check for locked conditional move, required for nonblocking stack
# implementations
AC_MSG_CHECKING([for atomic __sync_val_compare_and_swap])
AC_TRY_COMPILE([],[
 unsigned long v = 0;
 unsigned long w = 0;
 unsigned long r = 1;

 if (__sync_val_compare_and_swap(&v,w,r) != w)
    return 10;
],
[ac_atomic_compare_and_swap='yes';AC_DEFINE(HAVE_ATOMIC_COMPARE_AND_SWAP,[1],[Define to 1 if __sync_val_compare_and_swap is available])],
[ac_atomic_compare_and_swap='no'])
AC_MSG_RESULT($ac_atomic_compare_and_swap)
#
# Check for a reasonable alignment for data structures. This should be a) a power of two,
# and b) large enough, and c) cover the alignment constraints of all basic types. This
# is required for the built-in memory manager
AC_MSG_CHECKING([for worst-case structural alignment])
AC_TRY_RUN([
int main(int argc,char **argv)
{
  union Align {
    char    a_byte;
    short   a_word;
    long    a_int;
    float   a_float;
    double  a_double;
#if SIZEOF_LONG_LONG > 0
    long long a_quad;
#elif SIZEOF___INT64 > 0
    __int64   a_quad;
#endif
    void   *a_ptr;
    struct {
      void *b_ptr;
    } a_struct;
  };
  union Align a[2];
  unsigned long s = (sizeof(a) >> 1) - 1;
  unsigned long p = 0;

  while(s) {
   s >>= 1;
   p++;
  }

  if (p < 4)
    p = 4;

  return p;
}
],[ac_natural_alignment='no'],[ac_natural_alignment=$?;AC_DEFINE_UNQUOTED(NATURAL_ALIGNMENT,[$ac_natural_alignment],[Define to the exponent of a power of two giving the worst-case alignment of components])])
AC_MSG_RESULT($ac_natural_alignment)
#
# Check whether private subclasses have access to private members.
# According to the C++ standard, they should, but for some compilers,
# they don't. This is a bug in g++ 2.95.4 and before, got fixed in 3.2
AC_MSG_CHECKING([whether private subclasses have access to private members])
AC_TRY_COMPILE([],[
class A {
 int a;
 class B {
  B(class A *a)
  {a->a = 0;}
 };
};
],[ac_private_access='yes';AC_DEFINE(HAS_PRIVATE_ACCESS,[1],[Define to 1 if subclasses have access to private members])],
[ac_private_access='no'])
AC_MSG_RESULT($ac_private_access)
#
# Check whether templated subclasses used in subclasses require explicitly the name space
# of the parent class to work. This should not happen, but gcc 2.95 has a bug here.
AC_MSG_CHECKING([whether templates are in local namespace])
AC_TRY_COMPILE([
class A {
 template<int a>
 class B {
 int b;
 B() : b(a) {}
 };
 class C {
 B<0> b;
 };
};],[],
[ac_local_templates='yes';AC_DEFINE(HAS_LOCAL_TEMPLATES,[1],[Define to 1 if templated subclasses are correctly in the namespace of the parent class])],
[ac_local_templates='no'])
AC_MSG_RESULT($ac_local_templates)
#
#
# Check whether static const integral initializers work
# Some compilers don't support them properly, but gcc does.
AC_MSG_CHECKING([whether initializers of static const integral members work])
AC_TRY_COMPILE([
class A {
 static const int a=0;
};
],[],
[ac_member_init='yes';AC_DEFINE(HAS_MEMBER_INIT,[1],[Define to 1 if initializers of static const integral members work])],
[ac_member_init='no'])
AC_MSG_RESULT($ac_member_init)
#
# Check whether casting works in template arguments. This doesn't seem to apply for 
# all compiles, so be a bit careful.
AC_MSG_CHECKING([whether casting works in template arguments])
AC_TRY_COMPILE([
typedef unsigned char UC;
template<UC a>
struct A {
 int b;
 A() : b(a) {}
};],[A<UC(~1)> a;],
[ac_template_casts='yes';AC_DEFINE(HAS_TEMPLATE_CASTS,[1],[Define to 1 if casting in template arguments work])],
[ac_template_casts='no'])
AC_MSG_RESULT($ac_template_casts)
#
#
# Check whether the NORETURN attribute is available
CXXFLAGS_KEEP="${CXXFLAGS}"
CXXFLAGS="${CXXFLAGS} -Werror"
AC_MSG_CHECKING([whether the noreturn attribute is available])
AC_TRY_COMPILE([
#include <stdlib.h>
void leave(int code) __attribute__ ((noreturn));
void leave(int code)
{
 exit(code);
}],[leave(0);],
[ac_have_noreturn='yes';AC_DEFINE(HAVE_NORETURN,[1],[Define to 1 if the noreturn attribute is available])],
[ac_have_noreturn='no'])
AC_MSG_RESULT($ac_have_noreturn)
#
# Check whether the ALWAYS_INLINE attribute is available
AC_MSG_CHECKING([whether the always_inline attribute is available])
AC_TRY_COMPILE([
int test(int code) __attribute__ ((always_inline));
int test(int code)
{
 return code;
}
],[return test(0)],
[ac_have_always_inline='yes';AC_DEFINE(HAVE_ALWAYS_INLINE,[1],
[Define to 1 if the always_inline attribute is available])],[ac_have_always_inline='no'])
AC_MSG_RESULT($ac_have_always_inline)
#
# Check for the "hidden" attribute to remove symbols from the list of
# symbols exported by a library.
AC_MSG_CHECKING([whether __attribute__((visibility("hidden"))) is available for types])
AC_TRY_COMPILE([struct A { static void f(void); }; void __attribute__ ((visibility ("hidden"))) A::f(void){}],[],[ac_visibility_hidden='yes';AC_DEFINE(HAS_VISIBILITY_HIDDEN,[1],[Define to 1 if __attribute((visibility("hidden"))) works])],[ac_visibility_hidden='no'])
AC_MSG_RESULT($ac_visibility_hidden)
#
# Check for the "internal" attribute to remove symbols from the list of
# symbols exported by a library.
AC_MSG_CHECKING([whether __attribute__((visibility("internal"))) is available for types])
AC_TRY_COMPILE([],[struct __attribute__ ((visibility ("internal"))) A { int x;};],[ac_visibility_internal='yes';AC_DEFINE(HAS_VISIBILITY_INTERNAL,[1],[Define to 1 if __attribute((visibility("internal"))) works])],[ac_visibility_internal='no'])
AC_MSG_RESULT($ac_visibility_internal)
#
# Check for the "default" attribute to remove symbols from the list of
# symbols exported by a library.
AC_MSG_CHECKING([whether __attribute__((visibility("default"))) is available for types])
AC_TRY_COMPILE([],[struct __attribute__ ((visibility ("default"))) A { int x;};],[ac_visibility_default='yes';AC_DEFINE(HAS_VISIBILITY_DEFAULT,[1],[Define to 1 if __attribute((visibility("default"))) works])],[ac_visibility_default='no'])
AC_MSG_RESULT($ac_visibility_default)
#
# Check for the "may_alias" attribute to indicate types that may alias
AC_MSG_CHECKING([whether __attribute__((may_alias)) is available for types])
AC_TRY_COMPILE([],[typedef short __attribute__((may_alias)) a_short;a_short a],[ac_may_alias='yes';AC_DEFINE(HAS_MAY_ALIAS,[1],[Define to 1 if __attribute((may_alias)) works])],[ac_may_alias='no'])
AC_MSG_RESULT($ac_may_alias)
#
# Check for the "aligned" attribute
AC_MSG_CHECKING([whether __attribute__((aligned)) is available for types])
AC_TRY_COMPILE([],[float x __attribute__((aligned));],[ac_aligned='yes';AC_DEFINE(HAS_ALIGNED,[1],[Define to 1 if __attribute((aligned)) works])],[ac_aligned='no'])
AC_MSG_RESULT($ac_aligned)
#
CXXFLAGS="${CXXFLAGS_KEEP}"
#
#
# Check for working const_cast: I'm not aware of a compiler
# that breaks this, but better keep care.
AC_MSG_CHECKING([for working const_cast<> capability])
AC_TRY_COMPILE([],[const char *a = 0;delete const_cast<char *>(a);],[ac_const_cast='yes';AC_DEFINE(HAS_CONST_CAST,[1],[Define to 1 if const_cast<> works])],[ac_const_cast='no'])
AC_MSG_RESULT($ac_const_cast)
#
# Check for working reinterpret_cast: I'm not aware of a compiler
# that breaks this, but better keep care.
AC_MSG_CHECKING([for working reinterpret_cast<> capability])
AC_TRY_COMPILE([],[float a = 0;int b = reinterpret_cast<int &>(a);],[ac_reinterpret_cast='yes';AC_DEFINE(HAS_REINTERPRET_CAST,[1],[Define to 1 if reinterpret_cast<> works])],[ac_reinterpret_cast='no'])
AC_MSG_RESULT($ac_reinterpret_cast)
##
# Check for non-ambiguity of static member functions thru various bases.
AC_MSG_CHECKING([for uniqueness of static members thru various derivation paths])
AC_TRY_COMPILE([],[
struct Base {
	static void operator delete(void *) { }
};
struct Path1 : public Base {
	int a;
};
struct Path2 : public Base {
	int b;
};
struct Final : public Path1, public Path2 {
	int c;
~Final() { }
};
],[ac_non_ambigious='yes'],[ac_non_ambigious='no';AC_DEFINE(AMBIGIOUS_NEW_BUG,[1],[Define to 1 if compiler threads static member derived from same base thru multiple paths as ambigious])])
AC_MSG_RESULT($ac_non_ambigious)
#
# Check whether we support restricted (non-aliasing) pointers.
AC_MSG_CHECKING([whether __restrict__ pointers are available])
AC_TRY_COMPILE([],[
struct SmartCopy {
	void mycopy(char * __restrict__ a,char * __restrict b)
	{
		while(*a++ = *b++);
	}
}
],[ac_have_restrict='yes';AC_DEFINE(HAVE_RESTRICTED_PTRS,[1],
[Define to 1 if the __restrict__ pointer attribute is available])],[ac_have_restrict='no'])
AC_MSG_RESULT($ac_have_restrict)
#
if test "$ac_arg_SIMD" = "yes"; then
# Check whether we have SIMD instructions for floating point. This can speed up at
# least the vertical lifting steps on some machines.
AC_MSG_CHECKING([for float SIMD instructions])
AC_TRY_COMPILE([
typedef float vector4 __attribute__ ((vector_size (16)));
typedef float vectorbase;
void vectorlift(vectorbase *top,vectorbase *center,vectorbase *bottom,int len)
{
  vector4 *tv = (vector4 *)top;
  vector4 *cv = (vector4 *)center;
  vector4 *bv = (vector4 *)bottom;
  const vector4 three = {3,3,3,3};
  
  len >>= 2;
  do {
    *cv  = (*bv + *tv) * three;
    cv++,bv++,tv++;
  } while(--len);
}
],[],
[ac_have_float_simd='yes';AC_DEFINE(HAVE_FLOAT_SIMD,[1],
[Define to 1 if float SIMD data types are available])],[ac_have_float_simd='no'])
AC_MSG_RESULT($ac_have_float_simd)
fi
#
# Check whether we are able to use some compile time options, as for example the
# traditional x87 FPU instruction set which is faster for the AMDs.
save_CFLAGS="$CFLAGS"
AC_LANG(C)
#
AC_MSG_CHECKING([for the -mfpmath=387 compiler switch])
CFLAGS="-mfpmath=387 $CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_x87FPU='yes';AC_SUBST(FPU_OPTS,"-mfpmath=387")],[ac_have_x87FPU='no'])
AC_MSG_RESULT($ac_have_x87FPU)
#
# Check whether the -fvisibility option is available. Can reduce the size of the library.
AC_MSG_CHECKING([for the -fvisibility=internal compiler switch])
CFLAGS="-fvisibility=internal -Werror $save_CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_fvisibility='yes';AC_SUBST(LIB_OPTS,"-fvisibility=internal")],[ac_have_fvisibility='no'])
AC_MSG_RESULT($ac_have_fvisibility)
#
# Check whether we can generate position-independent code. This is sometimes required for
# library building
AC_MSG_CHECKING([for the -fPIC compiler switch])
CFLAGS="-fPIC $save_CFLAGS"
AC_TRY_COMPILE([],[],[ac_have_fpic='yes';AC_SUBST(LIB_PICOPTS,"-fPIC")],[ac_have_fpic='no'])
AC_MSG_RESULT($ac_have_fpic)
#
#
CFLAGS="$save_CFLAGS"
AC_LANG(C++)
#
# Check for additional features for this hardware.
# Check whether we have a processor type. If not, set to
# "unknown" and check for uname -m.
HARDWARE=`(uname -p) 2>/dev/null || echo unknown`
if test "$HARDWARE" = "unknown"; then
   HARDWARE=`(uname -m) 2>/dev/null || echo unknown`
fi
#
# For hysterical raisons, "sparc" is kept here as "sun4u" Yuck.
if test "$HARDWARE" = "sparc"; then
   HARDWARE="sun4u"
fi
#
host_os=`(uname -s) 2>/dev/null || echo unknown`
host_cpu=${HARDWARE}
#
# Check for a suitable libpthread and the required compiler flags to make it working.
# Adapted from the autoconf code by Steven G. Johnson and Alejandro Forero Cuervo
# All this requires C linkage, so switch over for the next test.
if test "$ac_arg_THREADING" = "yes"; then
AC_LANG(C)
cx_pthread_ok=no
# We used to check for pthread.h first, but this fails if pthread.h
# requires special compiler flags (e.g. on True64 or Sequent).
# It gets checked for in the link test anyway.
# First of all, check if the user has set any of the PTHREAD_LIBS,
# etcetera environment variables, and if threads linking works using
# them:
if test "$PTHREAD_LIBS$PTHREAD_CFLAGS" != ""; then
   save_CFLAGS="$CFLAGS"
   CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
   save_LIBS="$LIBS"
   LIBS="$PTHREAD_LIBS $LIBS"
   AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS])
   AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes)
   AC_MSG_RESULT($acx_pthread_ok)
   if test "$acx_pthread_ok" = "no"; then
      PTHREAD_LIBS=""
      PTHREAD_CFLAGS=""
   fi
   LIBS="$save_LIBS"
   CFLAGS="$save_CFLAGS"
fi
# We must check for the threads library under a number of different
# names; the ordering is very important because some systems
# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
# libraries is broken (non-POSIX).

# Create a list of thread flags to try.  Items starting with a "-" are
# C compiler flags, and other items are library names, except for "none"
# which indicates that we try without any flags at all.

acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt"

# The ordering *is* (sometimes) important.  Some notes on the
# individual items follow:

# pthreads: AIX (must check this before -lpthread)
# none: in case threads are in libc; should be tried before -Kthread and
#       other compiler flags to prevent continual compiler warnings
# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads)
# -pthreads: Solaris/gcc
# -mthreads: Mingw32/gcc, Lynx/gcc
# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
#      doesn't hurt to check since this sometimes defines pthreads too;
#      also defines -D_REENTRANT)
# pthread: Linux, etcetera
# --thread-safe: KAI C++
case "${host_cpu}-${host_os}" in
     *sun4u*)
     # On Solaris (at least, for some versions), libc contains stubbed
     # (non-functional) versions of the pthreads routines, so link-based
     # tests will erroneously succeed.	(We need to link with -pthread or
     # -lpthread.)  (The stubs are missing pthread_cleanup_push, or rather
     # a function called by this macro, so we could check for that, but
     # who knows whether they'll stub that too in a future libc.)  So,
     # we'll just look for -pthreads and -lpthread first:
     acx_pthread_flags="-pthread -pthreads pthread -mt $acx_pthread_flags"
     ;;
esac

if test "$acx_pthread_ok" = ""; then
for flag in $acx_pthread_flags; do
    case $flag in
	 none)
		AC_MSG_CHECKING([whether pthreads work without any flags])
		;;

	-*)
		AC_MSG_CHECKING([whether pthreads work with $flag])
		PTHREAD_CFLAGS="$flag"
		;;

	*)
		AC_MSG_CHECKING([for the pthreads library -l$flag])
		PTHREAD_LIBS="-l$flag"
		;;
	esac

	save_LIBS="$LIBS"
	save_CFLAGS="$CFLAGS"
	LIBS="$PTHREAD_LIBS $LIBS"
	CFLAGS="$CFLAGS $PTHREAD_CFLAGS"

	# Check for various functions.	We must include pthread.h,
	# since some functions may be macros.  (On the Sequent, we
	# need a special flag -Kthread to make this header compile.)
	# We check for pthread_join because it is in -lpthread on IRIX
	# while pthread_create is in libc.  We check for pthread_attr_init
	# due to DEC craziness with -lpthreads.	 We check for
	# pthread_cleanup_push because it is one of the few pthread
	# functions on Solaris that doesn't have a non-functional libc stub.
	# We try pthread_create on general principles.
	AC_TRY_LINK([#include <pthread.h>],
		    [pthread_t th; pthread_join(th, 0);
		     pthread_attr_init(0); pthread_cleanup_push(0, 0);
		     pthread_create(0,0,0,0); pthread_cleanup_pop(0); ],
		    [acx_pthread_ok=yes])

	LIBS="$save_LIBS"
	CFLAGS="$save_CFLAGS"

	AC_MSG_RESULT($acx_pthread_ok)
	if test "$acx_pthread_ok" = "yes"; then
		break;
	fi

	PTHREAD_LIBS=""
	PTHREAD_CFLAGS=""
done
fi
#
# Various other checks:
if test "$acx_pthread_ok" = "yes"; then
        save_LIBS="$LIBS"
        LIBS="$PTHREAD_LIBS $LIBS"
        save_CFLAGS="$CFLAGS"
        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"

        # Detect AIX lossage: threads are created detached by default
        # and the JOINABLE attribute has a nonstandard name (UNDETACHED).
        AC_MSG_CHECKING([for joinable pthread attribute])
        AC_TRY_LINK([#include <pthread.h>],
                    [int attr=PTHREAD_CREATE_JOINABLE;],
                    ok=PTHREAD_CREATE_JOINABLE, ok=unknown)
        if test "$ok" = "unknown"; then
                AC_TRY_LINK([#include <pthread.h>],
                            [int attr=PTHREAD_CREATE_UNDETACHED;],
                            ok=PTHREAD_CREATE_UNDETACHED, ok=unknown)
        fi
        if test "$ok" != "PTHREAD_CREATE_JOINABLE"; then
                AC_DEFINE(PTHREAD_CREATE_JOINABLE, $ok,
                          [Define to the necessary symbol if this constant
                           uses a non-standard name on your system.])
        fi
        AC_MSG_RESULT(${ok})
        if test "$ok" = "unknown"; then
                AC_MSG_WARN([we do not know how to create joinable pthreads])
        fi
	#
	# Detect whether we can create pthreads in detached state
        AC_MSG_CHECKING([for detached pthread attribute])
        AC_TRY_LINK([#include <pthread.h>],
                    [int attr=PTHREAD_CREATE_DETACHED;],
                    ok=PTHREAD_CREATE_DETACHED, ok=unknown)
	if test "$ok" = "PTHREAD_CREATE_DETACHED"; then
	   AC_DEFINE(HAVE_PTHREAD_CREATE_DETACHED,1,[Define to 1 if PTHREAD_CREATE_DETACHED is available])
	fi						   
	AC_MSG_RESULT(${ok})

        AC_MSG_CHECKING([if more special flags are required for pthreads])
        flag=no
        case "${host_cpu}-${host_os}" in
                *-AIX* | *-freebsd*)     flag="-D_THREAD_SAFE";;
                *sun4u* | *-osf* | *-hpux*) flag="-D_REENTRANT";;
        esac
        AC_MSG_RESULT(${flag})
        if test "$flag" != "no"; then
                PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
        fi

        LIBS="$save_LIBS"
        CFLAGS="$save_CFLAGS"

        # More AIX lossage: must compile with cc_r
        AC_CHECK_PROG(PTHREAD_CC, cc_r, cc_r, ${CC})
else
        PTHREAD_CC="$CC"
fi
#
# Bummer! We cannot really use the CC command here since this is C++ code.
# Keep this set for future extensions/workarounds.
AC_SUBST(PTHREAD_CC)
#
if test "$acx_pthread_ok" = "yes"; then
   # Check for semaphore operations
   CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
   CC=$PTHREAD_CC
   AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.])
   AC_DEFINE(USE_MULTITHREADING,1,[Define if you want to use multithreading.])
   if test "$PTHREAD_LIBS" = ""; then
      ac_pthread_libs=""
   else
      ac_pthread_libs=`echo $PTHREAD_LIBS | sed 's/^-l//' | sed 's/ -l/ /g'`
   fi
   AC_SEARCH_LIBS([pthread_create],[$ac_pthread_libs])
   # Solaris has sem_init in a separate library
   save_LIBS="$LIBS"
   LIBS=""
   AC_SEARCH_LIBS([sem_init],[rt],[],[],[$save_LIBS])
   PTHREAD_LIBS="$PTHREAD_LIBS $LIBS"	
   LIBS="$PTHREAD_LIBS $LIBS"
   AC_CHECK_HEADERS([pthread.h semaphore.h])
   AC_CHECK_FUNCS([pthread_mutex_init pthread_create pthread_detach pthread_mutexattr_init sem_init])
   AC_CHECK_FUNCS([pthread_self pthread_equal])
   LIBS="$save_LIBS"
else   
   AC_MSG_ERROR(["pthreads not available, make sure that libpthread is in the LD_LIBRARY_PATH"])
   acx_pthread_ok=no
fi
AC_SUBST(PTHREAD_LIBS)
AC_SUBST(PTHREAD_CFLAGS)
#
if test "$ac_arg_ASSEMBLY" = "yes"; then
   ASSEMBLY_FLAG="-DUSE_ASSEMBLY=1"
else
   ASSEMBLY_FLAG="-DUSE_ASSEMBLY=1"
fi
AC_SUBST(ASSEMBLY_FLAG)
#
# Additional feature selection
#
AC_DEFINE(HAVE_FEATURE_SELECTION,1,[Define to 1 to use the autoconfig feature selection])
#
#
AC_MSG_CHECKING([for additional settings for ${HARDWARE}])
AC_SUBST(HARDWARE)
AC_DEFINE_UNQUOTED(HARDWARE,${HARDWARE},[Define for short name of hardware platform])
HW_DEFINE="-D__IS_${HARDWARE}__"
AC_SUBST(HW_DEFINE)
ADDON_FILE="addons.$HARDWARE"
if test -d "$ADDON_FILE"; then
   ac_have_settings='yes'
   AC_DEFINE(HAVE_ADDONS,1,[Define if additional settings are required for this architecture])
   AC_DEFINE_UNQUOTED(ADDON_FILE,${ADDON_FILE},[Define to path for platform specific include file])
   # Create a symbolic link to the addons we use for easier inclusion
   rm -rf addons
   ln -s $ADDON_FILE addons
else
   rm -rf addons
   ac_have_settings='no'
fi
AC_SUBST(HAVE_ADDONS,$ac_have_settings)
AC_MSG_RESULT($ac_have_settings)
#
#
AC_LANG(C++)
#
# End of: Configuration switch: Enable multi-threading
fi
#
#
AC_CONFIG_FILES([automakefile])
AC_OUTPUT
#