dnl This file is part of reSID, a MOS6581 SID emulator engine.
dnl Copyright (C) 2010  Dag Lem <resid@nimrod.no>
dnl
dnl Process this file with autoconf to produce a configure script.

dnl Use Autoconf
AC_PREREQ([2.56])
AC_INIT([reSID], [1.0-pre2], [resid@nimrod.no])
AC_CONFIG_SRCDIR([sid.h])

dnl Use Automake
AM_INIT_AUTOMAKE([1.7.1])

dnl Avoid "ar: `u' modifier ignored since `D' is the default (see `U')" warning
dnl caused by a longstanding bug in libtool.
dnl See https://github.com/rsyslog/rsyslog/issues/1179 for some details.
: ${ARFLAGS="cr"}
: ${AR_FLAGS="cr"}
AC_SUBST(ARFLAGS)
AC_SUBST(AR_FLAGS)

dnl Use Libtool
dnl LT_PREREQ([2.2.2])
dnl LT_INIT([disable-shared])
dnl AC_SUBST([LTVERSION], [6:0:0])

dnl Use C++ for tests.
AC_LANG([C++])

AC_CANONICAL_HOST

AC_MSG_CHECKING([for debugging])
AC_ARG_ENABLE(debug, [AS_HELP_STRING([--enable-debug], [whether to enable asserts (default is no)])],
 [], [enable_debug=no])

AS_IF([test "x$enable_debug" = "xno"],
  [AC_MSG_RESULT([build without asserts]); RESID_CPPFLAGS="-DNDEBUG"],
  [AC_MSG_RESULT([build with asserts]); RESID_CPPFLAGS=""]
)
AC_SUBST(RESID_CPPFLAGS)

dnl Enable inlining.
AC_ARG_ENABLE([inline],
  [AC_HELP_STRING([--enable-inline],
    [enable inlining of functions [default=yes]])],
  [],
  [enable_inline=yes])

AS_IF([test "$enable_inline" != no],
  [AC_SUBST([RESID_INLINING], [1])
   AC_SUBST([RESID_INLINE], [inline])],
  [AC_SUBST([RESID_INLINING], [0])
   AC_SUBST([RESID_INLINE], [])])

dnl Enable architecture specific compilation.
AC_ARG_ENABLE([arch],
  [AC_HELP_STRING([--enable-arch[[=arch]]],
    [enable architecture specific compilation [default=no]])],
  [],
  [enable_arch=yes])

dnl Enable branch prediction hints.
AC_ARG_ENABLE([branch-hints],
  [AC_HELP_STRING([--enable-branch-hints],
    [enable static branch prediction hints [default=yes]])],
  [],
  [enable_branch_hints=yes])

AS_IF([test "$enable_branch_hints" != no],
  [AC_SUBST([RESID_BRANCH_HINTS], [1])],
  [AC_SUBST([RESID_BRANCH_HINTS], [0])])

dnl Enable experimental 8580 filters.
AC_ARG_ENABLE([new8580filter],
  [AS_HELP_STRING([--disable-new8580filter],
    [disable new 8580 filter implementation [default=no]])]
)

AM_CONDITIONAL([NEW_8580_FILTER], [test x"$enable_new8580filter" != "xno"])
AS_IF([test x"$enable_new8580filter" != "xno"],
  [AC_SUBST([NEW_8580_FILTER], [1])],
  [AC_SUBST([NEW_8580_FILTER], [0])]
)

dnl Store CXXFLAGS status.
resid_test_CXXFLAGS=${CXXFLAGS+set}

dnl Checks for programs.
AC_PROG_CXX([c++ g++ clang++])

dnl Set CXXFLAGS for g++.
if test x"$enable_arch" = "xno"; then
  march=""
else
  if test x"$enable_arch" = "xyes"; then
    AC_MSG_CHECKING([if the compiler supports -march=native])
    ORIG_CXXFLAGS=$CXXFLAGS
    CXXFLAGS="$CXXFLAGS -march=native"
    AC_TRY_COMPILE([],
                   [int test;],
                   [ AC_MSG_RESULT(yes)
                     march="-march=native" ],
                   [ AC_MSG_RESULT(no)
                     march="" ])
    CXXFLAGS=$ORIG_CXXFLAGS
  else
    AC_MSG_CHECKING([if the compiler supports -march=$enable_arch])
    ORIG_CXXFLAGS=$CXXFLAGS
    CXXFLAGS="$CXXFLAGS -march=$enable_arch"
    AC_TRY_COMPILE([],
                   [int test;],
                   [ AC_MSG_RESULT(yes)
                     march="-march=$enable_arch" ],
                   [ AC_MSG_RESULT(no)
                     march="" ])
    CXXFLAGS=$ORIG_CXXFLAGS
  fi
fi

AS_IF([test "$GXX" = yes -a "$resid_test_CXXFLAGS" != set],
  [resid_save_CXXFLAGS=$CXXFLAGS
   CXXFLAGS="-g -Wall -O3 $march -fno-exceptions"
   AC_MSG_CHECKING([whether g++ accepts $CXXFLAGS])
   AC_COMPILE_IFELSE([int test;],
                     [AC_MSG_RESULT(yes)],
                     [AC_MSG_RESULT(no)
                      CXXFLAGS="-g -Wall -O3 -fno-exceptions"
                      AC_MSG_CHECKING([whether g++ accepts $CXXFLAGS])
                      AC_COMPILE_IFELSE([int test;],
                                        [AC_MSG_RESULT(yes)],
                                        [AC_MSG_RESULT(no)
                                         CXXFLAGS=$resid_save_CXXFLAGS])])])

case $host_os in
darwin*)
  dnl Support targeting a specific macOS version
  AC_ARG_ENABLE([macos-target-sdk-version],
    [AC_HELP_STRING([--enable-macos-target-sdk-version[[=version]]],
      [compile for a specific sdk version such as 10.10 [default=no]])],
    [],
    [enable_macos_target_sdk_version=10.10])
  AS_IF([test "$enable_macos_target_sdk_version" != no],
   [CFLAGS="$CFLAGS -mmacosx-version-min=$enable_macos_target_sdk_version"
    OBJCFLAGS="$OBJCFLAGS -mmacosx-version-min=$enable_macos_target_sdk_version"
    CXXFLAGS="$CXXFLAGS -mmacosx-version-min=$enable_macos_target_sdk_version"
    LDFLAGS="$LDFLAGS -mmacosx-version-min=$enable_macos_target_sdk_version"])
  ;;
*)
  ;;
esac

AC_CHECK_PROG([AR], [ar], [ar], [ar])
AC_PROG_RANLIB
AC_PATH_PROG([PERL], [perl])

dnl Checks for libraries.

dnl Checks for header files.
AC_CHECK_HEADER([math.h], [], AC_MSG_ERROR([missing math.h]))

dnl Checks for typedefs, structures, and compiler characteristics.
AC_CHECK_SIZEOF([int], [4])

AS_IF([test $ac_cv_sizeof_int -lt 4],
  AC_MSG_ERROR([only 32 bit or better CPUs are supported]))

AC_CACHE_CHECK([for working bool], [resid_cv_cxx_bool],
  [AC_COMPILE_IFELSE([bool flag;],
    [resid_cv_cxx_bool=yes], [resid_cv_cxx_bool=no])])

AS_IF([test "$resid_cv_cxx_bool" = no],
  [AC_SUBST([HAVE_BOOL], [0])],
  [AC_SUBST([HAVE_BOOL], [1])])

AC_CACHE_CHECK([for __builtin_expect], [resid_cv_builtin_expect],
  [AC_COMPILE_IFELSE([int main() { __builtin_expect(0, 0); }],
    [resid_cv_builtin_expect=yes], [resid_cv_builtin_expect=no])])

AS_IF([test "$resid_cv_builtin_expect" = no],
  [AC_SUBST([HAVE_BUILTIN_EXPECT], [0])],
  [AC_SUBST([HAVE_BUILTIN_EXPECT], [1])])

AC_CACHE_CHECK([for log1p], [resid_cv_log1p],
  [AC_TRY_COMPILE([#include <math.h>], [ log1p(1); ],
    resid_cv_log1p=yes, resid_cv_log1p=no)])

AS_IF([test "$resid_cv_log1p" = no],
  [AC_SUBST([HAVE_LOG1P], [0])],
  [AC_SUBST([HAVE_LOG1P], [1])])

AC_CONFIG_FILES([Makefile siddefs.h])
AC_OUTPUT