postgresql/configure.in

dnl Process this file with autoconf to produce a configure script.
dnl configure.in
dnl
dnl Developers, please strive to achieve this order:
dnl
dnl 0. Initialization and options processing
dnl 1. Programs
dnl 2. Libraries
dnl 3. Header files
dnl 4. Types
dnl 5. Structures
dnl 6. Compiler characteristics
dnl 7. Functions, global variables
dnl 8. System services
dnl
dnl Read the Autoconf manual for details.
dnl
m4_pattern_forbid(^PGAC_)dnl to catch undefined macros

AC_INIT([PostgreSQL], [10devel], [pgsql-bugs@postgresql.org])

m4_if(m4_defn([m4_PACKAGE_VERSION]), [2.69], [], [m4_fatal([Autoconf version 2.69 is required.
Untested combinations of 'autoconf' and PostgreSQL versions are not
recommended.  You can remove the check from 'configure.in' but it is then
your responsibility whether the result works or not.])])
AC_COPYRIGHT([Copyright (c) 1996-2017, PostgreSQL Global Development Group])
AC_CONFIG_SRCDIR([src/backend/access/common/heaptuple.c])
AC_CONFIG_AUX_DIR(config)
AC_PREFIX_DEFAULT(/usr/local/pgsql)
AC_SUBST(configure_args, [$ac_configure_args])

[PG_MAJORVERSION=`expr "$PACKAGE_VERSION" : '\([0-9][0-9]*\)'`]
AC_SUBST(PG_MAJORVERSION)
AC_DEFINE_UNQUOTED(PG_MAJORVERSION, "$PG_MAJORVERSION", [PostgreSQL major version as a string])

PGAC_ARG_REQ(with, extra-version, [STRING], [append STRING to version],
             [PG_VERSION="$PACKAGE_VERSION$withval"],
             [PG_VERSION="$PACKAGE_VERSION"])
AC_DEFINE_UNQUOTED(PG_VERSION, "$PG_VERSION", [PostgreSQL version as a string])

AC_CANONICAL_HOST

template=
AC_MSG_CHECKING([which template to use])

PGAC_ARG_REQ(with, template, [NAME], [override operating system template],
[
  case $withval in
    list)   echo; ls "$srcdir/src/template"; exit;;
    *)      if test -f "$srcdir/src/template/$with_template" ; then
              template=$withval
            else
              AC_MSG_ERROR(['$withval' is not a valid template name. Use 'list' for a list.])
            fi;;
  esac
],
[
# --with-template not given

case $host_os in
     aix*) template=aix ;;
  cygwin*) template=cygwin ;;
  darwin*) template=darwin ;;
dragonfly*) template=netbsd ;;
 freebsd*) template=freebsd ;;
    hpux*) template=hpux ;;
 linux*|gnu*|k*bsd*-gnu)
           template=linux ;;
   mingw*) template=win32 ;;
  netbsd*) template=netbsd ;;
 openbsd*) template=openbsd ;;
 solaris*) template=solaris ;;
esac

  if test x"$template" = x"" ; then
    AC_MSG_ERROR([[
*******************************************************************
PostgreSQL has apparently not been ported to your platform yet.
To try a manual configuration, look into the src/template directory
for a similar platform and use the '--with-template=' option.

Please also contact <pgsql-bugs@postgresql.org> to see about
rectifying this.  Include the above 'checking host system type...'
line.
*******************************************************************
]])
  fi

])

AC_MSG_RESULT([$template])

PORTNAME=$template
AC_SUBST(PORTNAME)

# Initialize default assumption that we do not need separate assembly code
# for TAS (test-and-set).  This can be overridden by the template file
# when it's executed.
need_tas=no
tas_file=dummy.s



##
## Command line options
##

#
# Add non-standard directories to the include path
#
PGAC_ARG_REQ(with, includes, [DIRS], [look for additional header files in DIRS])


#
# Add non-standard directories to the library search path
#
PGAC_ARG_REQ(with, libraries, [DIRS], [look for additional libraries in DIRS],
             [LIBRARY_DIRS=$withval])

PGAC_ARG_REQ(with, libs,      [DIRS], [alternative spelling of --with-libraries],
             [LIBRARY_DIRS=$withval])


#
# 64-bit integer date/time storage is now the only option, but to avoid
# unnecessary breakage of build scripts, continue to accept an explicit
# "--enable-integer-datetimes" switch.
#
PGAC_ARG_BOOL(enable, integer-datetimes, yes, [obsolete option, no longer supported],
              [],
              [AC_MSG_ERROR([--disable-integer-datetimes is no longer supported])])


#
# NLS
#
AC_MSG_CHECKING([whether NLS is wanted])
PGAC_ARG_OPTARG(enable, nls,
                [LANGUAGES], [enable Native Language Support],
                [],
                [WANTED_LANGUAGES=$enableval],
                [AC_DEFINE(ENABLE_NLS, 1,
                           [Define to 1 if you want National Language Support. (--enable-nls)])])
AC_MSG_RESULT([$enable_nls])
AC_SUBST(enable_nls)
AC_SUBST(WANTED_LANGUAGES)

#
# Default port number (--with-pgport), default 5432
#
AC_MSG_CHECKING([for default port number])
PGAC_ARG_REQ(with, pgport, [PORTNUM], [set default port number [5432]],
             [default_port=$withval],
             [default_port=5432])
AC_MSG_RESULT([$default_port])
# Need both of these because some places want an integer and some a string
AC_DEFINE_UNQUOTED(DEF_PGPORT, ${default_port},
[Define to the default TCP port number on which the server listens and
to which clients will try to connect.  This can be overridden at run-time,
but it's convenient if your clients have the right default compiled in.
(--with-pgport=PORTNUM)])
AC_DEFINE_UNQUOTED(DEF_PGPORT_STR, "${default_port}",
                   [Define to the default TCP port number as a string constant.])
AC_SUBST(default_port)

# It's worth validating port; you can get very confusing errors otherwise
if test x"$default_port" = x""; then
  AC_MSG_ERROR([invalid --with-pgport specification: empty string])
elif test ! x`echo "$default_port" | sed -e 's/[[0-9]]*//'` = x""; then
  AC_MSG_ERROR([invalid --with-pgport specification: must be a number])
elif test ! x`echo "$default_port" | sed -e 's/^0.//'` = x"$default_port"; then
  AC_MSG_ERROR([invalid --with-pgport specification: must not have leading 0])
elif test "$default_port" -lt "1" -o "$default_port" -gt "65535"; then
  AC_MSG_ERROR([invalid --with-pgport specification: must be between 1 and 65535])
fi

#
# '-rpath'-like feature can be disabled
#
PGAC_ARG_BOOL(enable, rpath, yes,
              [do not embed shared library search path in executables])
AC_SUBST(enable_rpath)

#
# Spinlocks
#
PGAC_ARG_BOOL(enable, spinlocks, yes,
              [do not use spinlocks])

#
# Atomic operations
#
PGAC_ARG_BOOL(enable, atomics, yes,
              [do not use atomic operations])

#
# Random number generation
#
PGAC_ARG_BOOL(enable, strong-random, yes,
              [do not use a strong random number source])
AC_SUBST(enable_strong_random)

#
# --enable-debug adds -g to compiler flags
#
PGAC_ARG_BOOL(enable, debug, no,
              [build with debugging symbols (-g)])
AC_SUBST(enable_debug)

#
# --enable-profiling enables gcc profiling
#
PGAC_ARG_BOOL(enable, profiling, no,
              [build with profiling enabled ])

#
# --enable-coverage enables generation of code coverage metrics with gcov
#
PGAC_ARG_BOOL(enable, coverage, no,
              [build with coverage testing instrumentation],
[AC_CHECK_PROGS(GCOV, gcov)
if test -z "$GCOV"; then
  AC_MSG_ERROR([gcov not found])
fi
AC_CHECK_PROGS(LCOV, lcov)
if test -z "$LCOV"; then
  AC_MSG_ERROR([lcov not found])
fi
AC_CHECK_PROGS(GENHTML, genhtml)
if test -z "$GENHTML"; then
  AC_MSG_ERROR([genhtml not found])
fi])
AC_SUBST(enable_coverage)

#
# DTrace
#
PGAC_ARG_BOOL(enable, dtrace, no,
              [build with DTrace support],
[AC_CHECK_PROGS(DTRACE, dtrace)
if test -z "$DTRACE"; then
  AC_MSG_ERROR([dtrace not found])
fi
AC_SUBST(DTRACEFLAGS)])
AC_SUBST(enable_dtrace)

#
# TAP tests
#
PGAC_ARG_BOOL(enable, tap-tests, no,
              [enable TAP tests (requires Perl and IPC::Run)])
AC_SUBST(enable_tap_tests)

#
# Block size
#
AC_MSG_CHECKING([for block size])
PGAC_ARG_REQ(with, blocksize, [BLOCKSIZE], [set table block size in kB [8]],
             [blocksize=$withval],
             [blocksize=8])
case ${blocksize} in
  1) BLCKSZ=1024;;
  2) BLCKSZ=2048;;
  4) BLCKSZ=4096;;
  8) BLCKSZ=8192;;
 16) BLCKSZ=16384;;
 32) BLCKSZ=32768;;
  *) AC_MSG_ERROR([Invalid block size. Allowed values are 1,2,4,8,16,32.])
esac
AC_MSG_RESULT([${blocksize}kB])

AC_DEFINE_UNQUOTED([BLCKSZ], ${BLCKSZ}, [
 Size of a disk block --- this also limits the size of a tuple.  You
 can set it bigger if you need bigger tuples (although TOAST should
 reduce the need to have large tuples, since fields can be spread
 across multiple tuples).

 BLCKSZ must be a power of 2.  The maximum possible value of BLCKSZ
 is currently 2^15 (32768).  This is determined by the 15-bit widths
 of the lp_off and lp_len fields in ItemIdData (see
 include/storage/itemid.h).

 Changing BLCKSZ requires an initdb.
])

#
# Relation segment size
#
AC_MSG_CHECKING([for segment size])
PGAC_ARG_REQ(with, segsize, [SEGSIZE], [set table segment size in GB [1]],
             [segsize=$withval],
             [segsize=1])
# this expression is set up to avoid unnecessary integer overflow
# blocksize is already guaranteed to be a factor of 1024
RELSEG_SIZE=`expr '(' 1024 / ${blocksize} ')' '*' ${segsize} '*' 1024`
test $? -eq 0 || exit 1
AC_MSG_RESULT([${segsize}GB])

AC_DEFINE_UNQUOTED([RELSEG_SIZE], ${RELSEG_SIZE}, [
 RELSEG_SIZE is the maximum number of blocks allowed in one disk file.
 Thus, the maximum size of a single file is RELSEG_SIZE * BLCKSZ;
 relations bigger than that are divided into multiple files.

 RELSEG_SIZE * BLCKSZ must be less than your OS' limit on file size.
 This is often 2 GB or 4GB in a 32-bit operating system, unless you
 have large file support enabled.  By default, we make the limit 1 GB
 to avoid any possible integer-overflow problems within the OS.
 A limit smaller than necessary only means we divide a large
 relation into more chunks than necessary, so it seems best to err
 in the direction of a small limit.

 A power-of-2 value is recommended to save a few cycles in md.c,
 but is not absolutely required.

 Changing RELSEG_SIZE requires an initdb.
])

#
# WAL block size
#
AC_MSG_CHECKING([for WAL block size])
PGAC_ARG_REQ(with, wal-blocksize, [BLOCKSIZE], [set WAL block size in kB [8]],
             [wal_blocksize=$withval],
             [wal_blocksize=8])
case ${wal_blocksize} in
  1) XLOG_BLCKSZ=1024;;
  2) XLOG_BLCKSZ=2048;;
  4) XLOG_BLCKSZ=4096;;
  8) XLOG_BLCKSZ=8192;;
 16) XLOG_BLCKSZ=16384;;
 32) XLOG_BLCKSZ=32768;;
 64) XLOG_BLCKSZ=65536;;
  *) AC_MSG_ERROR([Invalid WAL block size. Allowed values are 1,2,4,8,16,32,64.])
esac
AC_MSG_RESULT([${wal_blocksize}kB])

AC_DEFINE_UNQUOTED([XLOG_BLCKSZ], ${XLOG_BLCKSZ}, [
 Size of a WAL file block.  This need have no particular relation to BLCKSZ.
 XLOG_BLCKSZ must be a power of 2, and if your system supports O_DIRECT I/O,
 XLOG_BLCKSZ must be a multiple of the alignment requirement for direct-I/O
 buffers, else direct I/O may fail.

 Changing XLOG_BLCKSZ requires an initdb.
])

#
# WAL segment size
#
AC_MSG_CHECKING([for WAL segment size])
PGAC_ARG_REQ(with, wal-segsize, [SEGSIZE], [set WAL segment size in MB [16]],
             [wal_segsize=$withval],
             [wal_segsize=16])
case ${wal_segsize} in
  1) ;;
  2) ;;
  4) ;;
  8) ;;
 16) ;;
 32) ;;
 64) ;;
 128) ;;
 256) ;;
 512) ;;
 1024) ;;
  *) AC_MSG_ERROR([Invalid WAL segment size. Allowed values are 1,2,4,8,16,32,64,128,256,512,1024.])
esac
AC_MSG_RESULT([${wal_segsize}MB])

AC_DEFINE_UNQUOTED([XLOG_SEG_SIZE], [(${wal_segsize} * 1024 * 1024)], [
 XLOG_SEG_SIZE is the size of a single WAL file.  This must be a power of 2
 and larger than XLOG_BLCKSZ (preferably, a great deal larger than
 XLOG_BLCKSZ).

 Changing XLOG_SEG_SIZE requires an initdb.
])

#
# C compiler
#

# For historical reasons you can also use --with-CC to specify the C compiler
# to use, although the standard way to do this is to set the CC environment
# variable.
PGAC_ARG_REQ(with, CC, [CMD], [set compiler (deprecated)], [CC=$with_CC])

case $template in
  aix) pgac_cc_list="gcc xlc";;
    *) pgac_cc_list="gcc cc";;
esac

AC_PROG_CC([$pgac_cc_list])

# Check if it's Intel's compiler, which (usually) pretends to be gcc,
# but has idiosyncrasies of its own.  We assume icc will define
# __INTEL_COMPILER regardless of CFLAGS.
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [@%:@ifndef __INTEL_COMPILER
choke me
@%:@endif])], [ICC=yes], [ICC=no])

# Check if it's Sun Studio compiler. We assume that
# __SUNPRO_C will be defined for Sun Studio compilers
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [@%:@ifndef __SUNPRO_C
choke me
@%:@endif])], [SUN_STUDIO_CC=yes], [SUN_STUDIO_CC=no])

AC_SUBST(SUN_STUDIO_CC)

unset CFLAGS

#
# Read the template
#
. "$srcdir/src/template/$template" || exit

# CFLAGS are selected so:
# If the user specifies something in the environment, that is used.
# else:  If the template file set something, that is used.
# else:  If coverage was enabled, don't set anything.
# else:  If the compiler is GCC, then we use -O2.
# else:  If the compiler is something else, then we use -O, unless debugging.

if test "$ac_env_CFLAGS_set" = set; then
  CFLAGS=$ac_env_CFLAGS_value
elif test "${CFLAGS+set}" = set; then
  : # (keep what template set)
elif test "$enable_coverage" = yes; then
  : # no optimization by default
elif test "$GCC" = yes; then
  CFLAGS="-O2"
else
  # if the user selected debug mode, don't use -O
  if test "$enable_debug" != yes; then
    CFLAGS="-O"
  fi
fi

# CFLAGS we determined above will be added back at the end
user_CFLAGS=$CFLAGS
CFLAGS=""

# set CFLAGS_VECTOR from the environment, if available
if test "$ac_env_CFLAGS_VECTOR_set" = set; then
  CFLAGS_VECTOR=$ac_env_CFLAGS_VECTOR_value
fi

# Some versions of GCC support some additional useful warning flags.
# Check whether they are supported, and add them to CFLAGS if so.
# ICC pretends to be GCC but it's lying; it doesn't support these flags,
# but has its own.  Also check other compiler-specific flags here.

if test "$GCC" = yes -a "$ICC" = no; then
  CFLAGS="-Wall -Wmissing-prototypes -Wpointer-arith"
  # These work in some but not all gcc versions
  PGAC_PROG_CC_CFLAGS_OPT([-Wdeclaration-after-statement])
  PGAC_PROG_CC_CFLAGS_OPT([-Wendif-labels])
  PGAC_PROG_CC_CFLAGS_OPT([-Wmissing-format-attribute])
  # This was included in -Wall/-Wformat in older GCC versions
  PGAC_PROG_CC_CFLAGS_OPT([-Wformat-security])
  # Disable strict-aliasing rules; needed for gcc 3.3+
  PGAC_PROG_CC_CFLAGS_OPT([-fno-strict-aliasing])
  # Disable optimizations that assume no overflow; needed for gcc 4.3+
  PGAC_PROG_CC_CFLAGS_OPT([-fwrapv])
  # Disable FP optimizations that cause various errors on gcc 4.5+ or maybe 4.6+
  PGAC_PROG_CC_CFLAGS_OPT([-fexcess-precision=standard])
  # Optimization flags for specific files that benefit from vectorization
  PGAC_PROG_CC_VAR_OPT(CFLAGS_VECTOR, [-funroll-loops])
  PGAC_PROG_CC_VAR_OPT(CFLAGS_VECTOR, [-ftree-vectorize])
  # We want to suppress clang's unhelpful unused-command-line-argument warnings
  # but gcc won't complain about unrecognized -Wno-foo switches, so we have to
  # test for the positive form and if that works, add the negative form
  PGAC_PROG_CC_VAR_OPT(NOT_THE_CFLAGS, [-Wunused-command-line-argument])
  if test -n "$NOT_THE_CFLAGS"; then
    CFLAGS="$CFLAGS -Wno-unused-command-line-argument"
  fi
elif test "$ICC" = yes; then
  # Intel's compiler has a bug/misoptimization in checking for
  # division by NAN (NaN == 0), -mp1 fixes it, so add it to the CFLAGS.
  PGAC_PROG_CC_CFLAGS_OPT([-mp1])
  # Make sure strict aliasing is off (though this is said to be the default)
  PGAC_PROG_CC_CFLAGS_OPT([-fno-strict-aliasing])
elif test "$PORTNAME" = "aix"; then
  # AIX's xlc has to have strict aliasing turned off too
  PGAC_PROG_CC_CFLAGS_OPT([-qnoansialias])
  PGAC_PROG_CC_CFLAGS_OPT([-qlonglong])
elif test "$PORTNAME" = "hpux"; then
  # On some versions of HP-UX, libm functions do not set errno by default.
  # Fix that by using +Olibmerrno if the compiler recognizes it.
  PGAC_PROG_CC_CFLAGS_OPT([+Olibmerrno])
fi

AC_SUBST(CFLAGS_VECTOR, $CFLAGS_VECTOR)

# supply -g if --enable-debug
if test "$enable_debug" = yes && test "$ac_cv_prog_cc_g" = yes; then
  CFLAGS="$CFLAGS -g"
fi

# enable code coverage if --enable-coverage
if test "$enable_coverage" = yes; then
  if test "$GCC" = yes; then
    CFLAGS="$CFLAGS -fprofile-arcs -ftest-coverage"
  else
    AC_MSG_ERROR([--enable-coverage is supported only when using GCC])
  fi
fi

# enable profiling if --enable-profiling
if test "$enable_profiling" = yes && test "$ac_cv_prog_cc_g" = yes; then
  if test "$GCC" = yes; then
    AC_DEFINE([PROFILE_PID_DIR], 1,
           [Define to 1 to allow profiling output to be saved separately for each process.])
    CFLAGS="$CFLAGS -pg $PLATFORM_PROFILE_FLAGS"
  else
    AC_MSG_ERROR([--enable-profiling is supported only when using GCC])
  fi
fi

# We already have this in Makefile.win32, but configure needs it too
if test "$PORTNAME" = "win32"; then
  CPPFLAGS="$CPPFLAGS -I$srcdir/src/include/port/win32 -DEXEC_BACKEND"
fi

# Now that we're done automatically adding stuff to CFLAGS, put back the
# user-specified flags (if any) at the end.  This lets users override
# the automatic additions.
CFLAGS="$CFLAGS $user_CFLAGS"

# Check if the compiler still works with the final flag settings
AC_MSG_CHECKING([whether the C compiler still works])
AC_LINK_IFELSE([AC_LANG_PROGRAM([], [return 0;])],
  [AC_MSG_RESULT(yes)],
  [AC_MSG_RESULT(no)
   AC_MSG_ERROR([cannot proceed])])

# Defend against gcc -ffast-math
if test "$GCC" = yes; then
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [@%:@ifdef __FAST_MATH__
choke me
@%:@endif])], [], [AC_MSG_ERROR([do not put -ffast-math in CFLAGS])])
fi

AC_PROG_CPP
AC_SUBST(GCC)


#
# Set up TAS assembly code if needed; the template file has now had its
# chance to request this.
#
AC_CONFIG_LINKS([src/backend/port/tas.s:src/backend/port/tas/${tas_file}])

if test "$need_tas" = yes ; then
  TAS=tas.o
else
  TAS=""
fi
AC_SUBST(TAS)


#
# Automatic dependency tracking
#
PGAC_ARG_BOOL(enable, depend, no, [turn on automatic dependency tracking],
              [autodepend=yes])
AC_SUBST(autodepend)


#
# Enable assert checks
#
PGAC_ARG_BOOL(enable, cassert, no, [enable assertion checks (for debugging)],
              [AC_DEFINE([USE_ASSERT_CHECKING], 1,
                         [Define to 1 to build with assertion checks. (--enable-cassert)])])


#
# Include directories
#
ac_save_IFS=$IFS
IFS="${IFS}${PATH_SEPARATOR}"
# SRCH_INC comes from the template file
for dir in $with_includes $SRCH_INC; do
  if test -d "$dir"; then
    INCLUDES="$INCLUDES -I$dir"
  else
    AC_MSG_WARN([*** Include directory $dir does not exist.])
  fi
done
IFS=$ac_save_IFS
AC_SUBST(INCLUDES)


#
# Library directories
#
ac_save_IFS=$IFS
IFS="${IFS}${PATH_SEPARATOR}"
# LIBRARY_DIRS comes from command line, SRCH_LIB from template file.
for dir in $LIBRARY_DIRS $SRCH_LIB; do
  if test -d "$dir"; then
    LIBDIRS="$LIBDIRS -L$dir"
  else
    AC_MSG_WARN([*** Library directory $dir does not exist.])
  fi
done
IFS=$ac_save_IFS

#
# Enable thread-safe client libraries
#
AC_MSG_CHECKING([allow thread-safe client libraries])
PGAC_ARG_BOOL(enable, thread-safety, yes, [disable thread-safety in client libraries])
if test "$enable_thread_safety" = yes; then
  AC_DEFINE([ENABLE_THREAD_SAFETY], 1,
          [Define to 1 to build client libraries as thread-safe code. (--enable-thread-safety)])
fi
AC_MSG_RESULT([$enable_thread_safety])
AC_SUBST(enable_thread_safety)

#
# ICU
#
AC_MSG_CHECKING([whether to build with ICU support])
PGAC_ARG_BOOL(with, icu, no, [build with ICU support],
              [AC_DEFINE([USE_ICU], 1, [Define to build with ICU support. (--with-icu)])])
AC_MSG_RESULT([$with_icu])
AC_SUBST(with_icu)

if test "$with_icu" = yes; then
  PKG_CHECK_MODULES(ICU, icu-uc icu-i18n)
fi

#
# Optionally build Tcl modules (PL/Tcl)
#
AC_MSG_CHECKING([whether to build with Tcl])
PGAC_ARG_BOOL(with, tcl, no, [build Tcl modules (PL/Tcl)])
AC_MSG_RESULT([$with_tcl])
AC_SUBST([with_tcl])

# We see if the path to the Tcl/Tk configuration scripts is specified.
# This will override the use of tclsh to find the paths to search.

PGAC_ARG_REQ(with, tclconfig, [DIR], [tclConfig.sh is in DIR])

#
# Optionally build Perl modules (PL/Perl)
#
AC_MSG_CHECKING([whether to build Perl modules])
PGAC_ARG_BOOL(with, perl, no, [build Perl modules (PL/Perl)])
AC_MSG_RESULT([$with_perl])
AC_SUBST(with_perl)

#
# Optionally build Python modules (PL/Python)
#
AC_MSG_CHECKING([whether to build Python modules])
PGAC_ARG_BOOL(with, python, no, [build Python modules (PL/Python)])
AC_MSG_RESULT([$with_python])
AC_SUBST(with_python)

#
# GSSAPI
#
AC_MSG_CHECKING([whether to build with GSSAPI support])
PGAC_ARG_BOOL(with, gssapi, no, [build with GSSAPI support],
[
  AC_DEFINE(ENABLE_GSS, 1, [Define to build with GSSAPI support. (--with-gssapi)])
  krb_srvtab="FILE:\$(sysconfdir)/krb5.keytab"
])
AC_MSG_RESULT([$with_gssapi])


AC_SUBST(krb_srvtab)


#
# Kerberos configuration parameters
#
PGAC_ARG_REQ(with, krb-srvnam,
             [NAME], [default service principal name in Kerberos (GSSAPI) [postgres]],
             [],
             [with_krb_srvnam="postgres"])
AC_DEFINE_UNQUOTED([PG_KRB_SRVNAM], ["$with_krb_srvnam"],
                   [Define to the name of the default PostgreSQL service principal in Kerberos (GSSAPI). (--with-krb-srvnam=NAME)])


#
# PAM
#
AC_MSG_CHECKING([whether to build with PAM support])
PGAC_ARG_BOOL(with, pam, no,
              [build with PAM support],
              [AC_DEFINE([USE_PAM], 1, [Define to 1 to build with PAM support. (--with-pam)])])
AC_MSG_RESULT([$with_pam])


#
# BSD AUTH
#
AC_MSG_CHECKING([whether to build with BSD Authentication support])
PGAC_ARG_BOOL(with, bsd-auth, no,
              [build with BSD Authentication support],
              [AC_DEFINE([USE_BSD_AUTH], 1, [Define to 1 to build with BSD Authentication support. (--with-bsd-auth)])])
AC_MSG_RESULT([$with_bsd_auth])


#
# LDAP
#
AC_MSG_CHECKING([whether to build with LDAP support])
PGAC_ARG_BOOL(with, ldap, no,
              [build with LDAP support],
              [AC_DEFINE([USE_LDAP], 1, [Define to 1 to build with LDAP support. (--with-ldap)])])
AC_MSG_RESULT([$with_ldap])


#
# Bonjour
#
AC_MSG_CHECKING([whether to build with Bonjour support])
PGAC_ARG_BOOL(with, bonjour, no,
              [build with Bonjour support],
              [AC_DEFINE([USE_BONJOUR], 1, [Define to 1 to build with Bonjour support. (--with-bonjour)])])
AC_MSG_RESULT([$with_bonjour])


#
# OpenSSL
#
AC_MSG_CHECKING([whether to build with OpenSSL support])
PGAC_ARG_BOOL(with, openssl, no, [build with OpenSSL support],
              [AC_DEFINE([USE_OPENSSL], 1, [Define to build with OpenSSL support. (--with-openssl)])])
AC_MSG_RESULT([$with_openssl])
AC_SUBST(with_openssl)

#
# SELinux
#
AC_MSG_CHECKING([whether to build with SELinux support])
PGAC_ARG_BOOL(with, selinux, no, [build with SELinux support])
AC_SUBST(with_selinux)
AC_MSG_RESULT([$with_selinux])

#
# Systemd
#
AC_MSG_CHECKING([whether to build with systemd support])
PGAC_ARG_BOOL(with, systemd, no, [build with systemd support],
              [AC_DEFINE([USE_SYSTEMD], 1, [Define to build with systemd support. (--with-systemd)])])
AC_SUBST(with_systemd)
AC_MSG_RESULT([$with_systemd])

#
# Readline
#
PGAC_ARG_BOOL(with, readline, yes,
              [do not use GNU Readline nor BSD Libedit for editing])
# readline on MinGW has problems with backslashes in psql and other bugs.
# This is particularly a problem with non-US code pages.
# Therefore disable its use until we understand the cause. 2004-07-20
if test "$PORTNAME" = "win32"; then
  if test "$with_readline" = yes; then
    AC_MSG_WARN([*** Readline does not work on MinGW --- disabling])
    with_readline=no
  fi
fi


#
# Prefer libedit
#
PGAC_ARG_BOOL(with, libedit-preferred, no,
              [prefer BSD Libedit over GNU Readline])


#
# UUID library
#
# There are at least three UUID libraries in common use: the FreeBSD/NetBSD
# library, the e2fsprogs libuuid (now part of util-linux-ng), and the OSSP
# UUID library.  More than one of these might be present on a given platform,
# so we make the user say which one she wants.
#
PGAC_ARG_REQ(with, uuid, [LIB], [build contrib/uuid-ossp using LIB (bsd,e2fs,ossp)])
if test x"$with_uuid" = x"" ; then
  with_uuid=no
fi
PGAC_ARG_BOOL(with, ossp-uuid, no, [obsolete spelling of --with-uuid=ossp])
if test "$with_ossp_uuid" = yes ; then
  with_uuid=ossp
fi

if test "$with_uuid" = bsd ; then
  AC_DEFINE([HAVE_UUID_BSD], 1, [Define to 1 if you have BSD UUID support.])
  UUID_EXTRA_OBJS="md5.o sha1.o"
elif test "$with_uuid" = e2fs ; then
  AC_DEFINE([HAVE_UUID_E2FS], 1, [Define to 1 if you have E2FS UUID support.])
  UUID_EXTRA_OBJS="md5.o sha1.o"
elif test "$with_uuid" = ossp ; then
  AC_DEFINE([HAVE_UUID_OSSP], 1, [Define to 1 if you have OSSP UUID support.])
  UUID_EXTRA_OBJS=""
elif test "$with_uuid" = no ; then
  UUID_EXTRA_OBJS=""
else
  AC_MSG_ERROR([--with-uuid must specify one of bsd, e2fs, or ossp])
fi
AC_SUBST(with_uuid)
AC_SUBST(UUID_EXTRA_OBJS)


#
# XML
#
PGAC_ARG_BOOL(with, libxml, no, [build with XML support],
              [AC_DEFINE([USE_LIBXML], 1, [Define to 1 to build with XML support. (--with-libxml)])])

if test "$with_libxml" = yes ; then
  AC_CHECK_PROGS(XML2_CONFIG, xml2-config)
  if test -n "$XML2_CONFIG"; then
    for pgac_option in `$XML2_CONFIG --cflags`; do
      case $pgac_option in
        -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
      esac
    done
    for pgac_option in `$XML2_CONFIG --libs`; do
      case $pgac_option in
        -L*) LDFLAGS="$LDFLAGS $pgac_option";;
      esac
    done
  fi
fi

AC_SUBST(with_libxml)

#
# XSLT
#
PGAC_ARG_BOOL(with, libxslt, no, [use XSLT support when building contrib/xml2],
              [AC_DEFINE([USE_LIBXSLT], 1, [Define to 1 to use XSLT support when building contrib/xml2. (--with-libxslt)])])


AC_SUBST(with_libxslt)

#
# tzdata
#
PGAC_ARG_REQ(with, system-tzdata,
             [DIR], [use system time zone data in DIR])
AC_SUBST(with_system_tzdata)

#
# Zlib
#
PGAC_ARG_BOOL(with, zlib, yes,
              [do not use Zlib])
AC_SUBST(with_zlib)

#
# Elf
#

# Assume system is ELF if it predefines __ELF__ as 1,
# otherwise believe host_os based default.
case $host_os in
    freebsd1*|freebsd2*) elf=no;;
    freebsd3*|freebsd4*) elf=yes;;
esac

AC_EGREP_CPP(yes,
[#if __ELF__
  yes
#endif
],
[ELF_SYS=true],
[if test "X$elf" = "Xyes" ; then
  ELF_SYS=true
else
  ELF_SYS=
fi])
AC_SUBST(ELF_SYS)

#
# Assignments
#

CPPFLAGS="$CPPFLAGS $INCLUDES"
LDFLAGS="$LDFLAGS $LIBDIRS"

AC_ARG_VAR(LDFLAGS_EX, [extra linker flags for linking executables only])
AC_ARG_VAR(LDFLAGS_SL, [extra linker flags for linking shared libraries only])

PGAC_PROG_LD
AC_SUBST(LD)
AC_SUBST(with_gnu_ld)
AC_PROG_RANLIB
PGAC_CHECK_STRIP
AC_CHECK_TOOL(AR, ar, ar)
if test "$PORTNAME" = "win32"; then
  AC_CHECK_TOOL(DLLTOOL, dlltool, dlltool)
  AC_CHECK_TOOL(DLLWRAP, dllwrap, dllwrap)
  AC_CHECK_TOOL(WINDRES, windres, windres)
fi

AC_PROG_INSTALL
# When Autoconf chooses install-sh as install program it tries to generate
# a relative path to it in each makefile where it substitutes it. This clashes
# with our Makefile.global concept. This workaround helps.
case $INSTALL in
  *install-sh*) install_bin='';;
  *) install_bin=$INSTALL;;
esac
AC_SUBST(install_bin)

AC_PATH_PROG(TAR, tar)
AC_PROG_LN_S
AC_PROG_AWK
AC_PROG_MKDIR_P
# When Autoconf chooses install-sh as mkdir -p program it tries to generate
# a relative path to it in each makefile where it substitutes it. This clashes
# with our Makefile.global concept. This workaround helps.
case $MKDIR_P in
  *install-sh*) MKDIR_P='\${SHELL} \${top_srcdir}/config/install-sh -c -d';;
esac

PGAC_PATH_BISON
PGAC_PATH_FLEX

PGAC_PATH_PERL
if test "$with_perl" = yes; then
  if test -z "$PERL"; then
    AC_MSG_ERROR([Perl not found])
  fi
  PGAC_CHECK_PERL_CONFIGS([archlibexp,privlibexp,useshrplib])
  if test "$perl_useshrplib" != yes && test "$perl_useshrplib" != true; then
    AC_MSG_ERROR([cannot build PL/Perl because libperl is not a shared library
You might have to rebuild your Perl installation.  Refer to the
documentation for details.  Use --without-perl to disable building
PL/Perl.])
  fi
  PGAC_CHECK_PERL_EMBED_LDFLAGS
fi

if test "$with_python" = yes; then
  PGAC_PATH_PYTHON
  PGAC_CHECK_PYTHON_EMBED_SETUP
fi

if test "$cross_compiling" = yes && test -z "$with_system_tzdata"; then
  AC_PATH_PROG(ZIC, zic)
  if test -z "$ZIC"; then
    AC_MSG_ERROR([
When cross-compiling, either use the option --with-system-tzdata to use
existing time-zone data, or set the environment variable ZIC to a zic
program to use during the build.])
  fi
fi

#
# Pthreads
#
# For each platform, we need to know about any special compile and link
# libraries, and whether the normal C function names are thread-safe.
# See the comment at the top of src/port/thread.c for more information.
# WIN32 doesn't need the pthread tests;  it always uses threads
#
# These tests are run before the library-tests, because linking with the
# other libraries can pull in the pthread functions as a side-effect.  We
# want to use the -pthread or similar flags directly, and not rely on
# the side-effects of linking with some other library.
#
# note: We have to use AS_IF here rather than plain if. The AC_CHECK_HEADER
# invocation below is the first one in the script, and autoconf generates
# additional code for that, which must not be inside the if-block. AS_IF
# knows how to do that.
AS_IF([test "$enable_thread_safety" = yes -a "$PORTNAME" != "win32"],
[ # then
AX_PTHREAD	# set thread flags

# Some platforms use these, so just define them.  They can't hurt if they
# are not supported.  For example, on Solaris -D_POSIX_PTHREAD_SEMANTICS
# enables 5-arg getpwuid_r, among other things.
PTHREAD_CFLAGS="$PTHREAD_CFLAGS -D_REENTRANT -D_THREAD_SAFE -D_POSIX_PTHREAD_SEMANTICS"

# Check for *_r functions
_CFLAGS="$CFLAGS"
_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$LIBS $PTHREAD_LIBS"

AC_CHECK_HEADER(pthread.h, [], [AC_MSG_ERROR([
pthread.h not found;  use --disable-thread-safety to disable thread safety])])

AC_CHECK_FUNCS([strerror_r getpwuid_r gethostbyname_r])

# Do test here with the proper thread flags
PGAC_FUNC_STRERROR_R_INT

CFLAGS="$_CFLAGS"
LIBS="$_LIBS"

], [ # else
# do not use values from template file
PTHREAD_CFLAGS=
PTHREAD_LIBS=
]) # fi

AC_SUBST(PTHREAD_CFLAGS)
AC_SUBST(PTHREAD_LIBS)


##
## Libraries
##
## Most libraries are included only if they demonstrably provide a function
## we need, but libm is an exception: always include it, because there are
## too many compilers that play cute optimization games that will break
## probes for standard functions such as pow().
##

AC_CHECK_LIB(m, main)
AC_SEARCH_LIBS(setproctitle, util)
AC_SEARCH_LIBS(dlopen, dl)
AC_SEARCH_LIBS(socket, [socket ws2_32])
AC_SEARCH_LIBS(shl_load, dld)
# We only use libld in port/dynloader/aix.c
case $host_os in
     aix*)
	AC_SEARCH_LIBS(ldopen, ld)
	;;
esac
AC_SEARCH_LIBS(getopt_long, [getopt gnugetopt])
AC_SEARCH_LIBS(crypt, crypt)
AC_SEARCH_LIBS(shm_open, rt)
AC_SEARCH_LIBS(shm_unlink, rt)
AC_SEARCH_LIBS(clock_gettime, [rt posix4])
# Solaris:
AC_SEARCH_LIBS(fdatasync, [rt posix4])
# Required for thread_test.c on Solaris
AC_SEARCH_LIBS(sched_yield, rt)
# Required for thread_test.c on Solaris 2.5:
# Other ports use it too (HP-UX) so test unconditionally
AC_SEARCH_LIBS(gethostbyname_r, nsl)
# Cygwin:
AC_SEARCH_LIBS(shmget, cygipc)

if test "$with_readline" = yes; then
  PGAC_CHECK_READLINE
  if test x"$pgac_cv_check_readline" = x"no"; then
    AC_MSG_ERROR([readline library not found
If you have readline already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-readline to disable readline support.])
  fi
fi

if test "$with_zlib" = yes; then
  AC_CHECK_LIB(z, inflate, [],
               [AC_MSG_ERROR([zlib library not found
If you have zlib already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-zlib to disable zlib support.])])
fi

if test "$enable_spinlocks" = yes; then
  AC_DEFINE(HAVE_SPINLOCKS, 1, [Define to 1 if you have spinlocks.])
else
  AC_MSG_WARN([
*** Not using spinlocks will cause poor performance.])
fi

if test "$enable_atomics" = yes; then
  AC_DEFINE(HAVE_ATOMICS, 1, [Define to 1 if you want to use atomics if available.])
else
  AC_MSG_WARN([
*** Not using atomic operations will cause poor performance.])
fi

if test "$with_gssapi" = yes ; then
  if test "$PORTNAME" != "win32"; then
    AC_SEARCH_LIBS(gss_init_sec_context, [gssapi_krb5 gss 'gssapi -lkrb5 -lcrypto'], [],
                   [AC_MSG_ERROR([could not find function 'gss_init_sec_context' required for GSSAPI])])
  else
    LIBS="$LIBS -lgssapi32"
  fi
fi

if test "$with_openssl" = yes ; then
  dnl Order matters!
  if test "$PORTNAME" != "win32"; then
     AC_CHECK_LIB(crypto, CRYPTO_new_ex_data, [], [AC_MSG_ERROR([library 'crypto' is required for OpenSSL])])
     AC_CHECK_LIB(ssl,    SSL_new, [], [AC_MSG_ERROR([library 'ssl' is required for OpenSSL])])
  else
     AC_SEARCH_LIBS(CRYPTO_new_ex_data, eay32 crypto, [], [AC_MSG_ERROR([library 'eay32' or 'crypto' is required for OpenSSL])])
     AC_SEARCH_LIBS(SSL_new, ssleay32 ssl, [], [AC_MSG_ERROR([library 'ssleay32' or 'ssl' is required for OpenSSL])])
  fi
  AC_CHECK_FUNCS([SSL_get_current_compression])
  # Functions introduced in OpenSSL 1.1.0. We used to check for
  # OPENSSL_VERSION_NUMBER, but that didn't work with 1.1.0, because LibreSSL
  # defines OPENSSL_VERSION_NUMBER to claim version 2.0.0, even though it
  # doesn't have these OpenSSL 1.1.0 functions. So check for individual
  # functions.
  AC_CHECK_FUNCS([OPENSSL_init_ssl BIO_get_data BIO_meth_new ASN1_STRING_get0_data RAND_OpenSSL])
  # OpenSSL versions before 1.1.0 required setting callback functions, for
  # thread-safety. In 1.1.0, it's no longer required, and CRYPTO_lock()
  # function was removed.
  AC_CHECK_FUNCS([CRYPTO_lock])
fi

if test "$with_pam" = yes ; then
  AC_CHECK_LIB(pam,    pam_start, [], [AC_MSG_ERROR([library 'pam' is required for PAM])])
fi

if test "$with_libxml" = yes ; then
  AC_CHECK_LIB(xml2, xmlSaveToBuffer, [], [AC_MSG_ERROR([library 'xml2' (version >= 2.6.23) is required for XML support])])
fi

if test "$with_libxslt" = yes ; then
  AC_CHECK_LIB(xslt, xsltCleanupGlobals, [], [AC_MSG_ERROR([library 'xslt' is required for XSLT support])])
fi

# Note: We can test for libldap_r only after we know PTHREAD_LIBS
if test "$with_ldap" = yes ; then
  _LIBS="$LIBS"
  if test "$PORTNAME" != "win32"; then
    AC_CHECK_LIB(ldap, ldap_bind, [],
		 [AC_MSG_ERROR([library 'ldap' is required for LDAP])],
		 [$EXTRA_LDAP_LIBS])
    LDAP_LIBS_BE="-lldap $EXTRA_LDAP_LIBS"
    if test "$enable_thread_safety" = yes; then
      # on some platforms ldap_r fails to link without PTHREAD_LIBS
      AC_CHECK_LIB(ldap_r, ldap_simple_bind, [],
		   [AC_MSG_ERROR([library 'ldap_r' is required for LDAP])],
		   [$PTHREAD_CFLAGS $PTHREAD_LIBS $EXTRA_LDAP_LIBS])
      LDAP_LIBS_FE="-lldap_r $EXTRA_LDAP_LIBS"
    else
      LDAP_LIBS_FE="-lldap $EXTRA_LDAP_LIBS"
    fi
  else
    AC_CHECK_LIB(wldap32, ldap_bind, [], [AC_MSG_ERROR([library 'wldap32' is required for LDAP])])
    LDAP_LIBS_FE="-lwldap32"
    LDAP_LIBS_BE="-lwldap32"
  fi
  LIBS="$_LIBS"
fi
AC_SUBST(LDAP_LIBS_FE)
AC_SUBST(LDAP_LIBS_BE)

# for contrib/sepgsql
if test "$with_selinux" = yes; then
  AC_CHECK_LIB(selinux, security_compute_create_name, [],
               [AC_MSG_ERROR([library 'libselinux', version 2.1.10 or newer, is required for SELinux support])])
fi

# for contrib/uuid-ossp
if test "$with_uuid" = bsd ; then
  # On BSD, the UUID functions are in libc
  AC_CHECK_FUNC(uuid_to_string,
    [UUID_LIBS=""],
    [AC_MSG_ERROR([BSD UUID functions are not present])])
elif test "$with_uuid" = e2fs ; then
  # On macOS, the UUID functions are in libc
  AC_CHECK_FUNC(uuid_generate,
    [UUID_LIBS=""],
    [AC_CHECK_LIB(uuid, uuid_generate,
      [UUID_LIBS="-luuid"],
      [AC_MSG_ERROR([library 'uuid' is required for E2FS UUID])])])
elif test "$with_uuid" = ossp ; then
  AC_CHECK_LIB(ossp-uuid, uuid_export,
    [UUID_LIBS="-lossp-uuid"],
    [AC_CHECK_LIB(uuid, uuid_export,
      [UUID_LIBS="-luuid"],
      [AC_MSG_ERROR([library 'ossp-uuid' or 'uuid' is required for OSSP UUID])])])
fi
AC_SUBST(UUID_LIBS)


##
## Header files
##

AC_CHECK_HEADERS([atomic.h crypt.h dld.h fp_class.h getopt.h ieeefp.h ifaddrs.h langinfo.h mbarrier.h poll.h sys/epoll.h sys/ipc.h sys/poll.h sys/pstat.h sys/resource.h sys/select.h sys/sem.h sys/shm.h sys/sockio.h sys/tas.h sys/un.h termios.h ucred.h utime.h wchar.h wctype.h])

# On BSD, test for net/if.h will fail unless sys/socket.h
# is included first.
AC_CHECK_HEADERS(net/if.h, [], [],
[AC_INCLUDES_DEFAULT
#include <sys/socket.h>
])

# On OpenBSD, test for sys/ucred.h will fail unless sys/param.h
# is included first.
AC_CHECK_HEADERS(sys/ucred.h, [], [],
[AC_INCLUDES_DEFAULT
#include <sys/param.h>
])

# At least on IRIX, test for netinet/tcp.h will fail unless
# netinet/in.h is included first.
AC_CHECK_HEADERS(netinet/tcp.h, [], [],
[AC_INCLUDES_DEFAULT
#include <netinet/in.h>
])

if expr x"$pgac_cv_check_readline" : 'x-lreadline' >/dev/null ; then
  AC_CHECK_HEADERS(readline/readline.h, [],
        [AC_CHECK_HEADERS(readline.h, [],
                [AC_MSG_ERROR([readline header not found
If you have readline already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-readline to disable readline support.])])])
  AC_CHECK_HEADERS(readline/history.h, [],
        [AC_CHECK_HEADERS(history.h, [],
                [AC_MSG_ERROR([history header not found
If you have readline already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-readline to disable readline support.])])])
fi

if expr x"$pgac_cv_check_readline" : 'x-ledit' >/dev/null ; then
# Some installations of libedit usurp /usr/include/readline/, which seems
# bad practice, since in combined installations readline will have its headers
# there.  We might have to resort to AC_EGREP checks to make sure we found
# the proper header...
  AC_CHECK_HEADERS(editline/readline.h, [],
        [AC_CHECK_HEADERS(readline.h, [],
                [AC_CHECK_HEADERS(readline/readline.h, [],
                        [AC_MSG_ERROR([readline header not found
If you have libedit already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-readline to disable libedit support.])])])])
# Note: in a libedit installation, history.h is sometimes a dummy, and may
# not be there at all.  Hence, don't complain if not found.  We must check
# though, since in yet other versions it is an independent header.
  AC_CHECK_HEADERS(editline/history.h, [],
        [AC_CHECK_HEADERS(history.h, [],
                [AC_CHECK_HEADERS(readline/history.h)])])
fi

if test "$with_zlib" = yes; then
  AC_CHECK_HEADER(zlib.h, [], [AC_MSG_ERROR([zlib header not found
If you have zlib already installed, see config.log for details on the
failure.  It is possible the compiler isn't looking in the proper directory.
Use --without-zlib to disable zlib support.])])
fi

if test "$with_gssapi" = yes ; then
  AC_CHECK_HEADERS(gssapi/gssapi.h, [],
	[AC_CHECK_HEADERS(gssapi.h, [], [AC_MSG_ERROR([gssapi.h header file is required for GSSAPI])])])
fi

if test "$with_openssl" = yes ; then
  AC_CHECK_HEADER(openssl/ssl.h, [], [AC_MSG_ERROR([header file <openssl/ssl.h> is required for OpenSSL])])
  AC_CHECK_HEADER(openssl/err.h, [], [AC_MSG_ERROR([header file <openssl/err.h> is required for OpenSSL])])
fi

if test "$with_pam" = yes ; then
  AC_CHECK_HEADERS(security/pam_appl.h, [],
                   [AC_CHECK_HEADERS(pam/pam_appl.h, [],
                                     [AC_MSG_ERROR([header file <security/pam_appl.h> or <pam/pam_appl.h> is required for PAM.])])])
fi

if test "$with_bsd_auth" = yes ; then
  AC_CHECK_HEADER(bsd_auth.h, [], [AC_MSG_ERROR([header file <bsd_auth.h> is required for BSD Authentication support])])
fi

if test "$with_systemd" = yes ; then
  AC_CHECK_HEADER(systemd/sd-daemon.h, [], [AC_MSG_ERROR([header file <systemd/sd-daemon.h> is required for systemd support])])
fi

if test "$with_libxml" = yes ; then
  AC_CHECK_HEADER(libxml/parser.h, [], [AC_MSG_ERROR([header file <libxml/parser.h> is required for XML support])])
fi

if test "$with_libxslt" = yes ; then
  AC_CHECK_HEADER(libxslt/xslt.h, [], [AC_MSG_ERROR([header file <libxslt/xslt.h> is required for XSLT support])])
fi

if test "$with_ldap" = yes ; then
  if test "$PORTNAME" != "win32"; then
     AC_CHECK_HEADERS(ldap.h, [],
                      [AC_MSG_ERROR([header file <ldap.h> is required for LDAP])])
     PGAC_LDAP_SAFE
  else
     AC_CHECK_HEADERS(winldap.h, [],
                      [AC_MSG_ERROR([header file <winldap.h> is required for LDAP])],
                      [AC_INCLUDES_DEFAULT
#include <windows.h>
                      ])
  fi
fi

if test "$with_bonjour" = yes ; then
  AC_CHECK_HEADER(dns_sd.h, [], [AC_MSG_ERROR([header file <dns_sd.h> is required for Bonjour])])
fi

# for contrib/uuid-ossp
if test "$with_uuid" = bsd ; then
  AC_CHECK_HEADERS(uuid.h,
    [AC_EGREP_HEADER([uuid_to_string], uuid.h, [],
      [AC_MSG_ERROR([header file <uuid.h> does not match BSD UUID library])])],
    [AC_MSG_ERROR([header file <uuid.h> is required for BSD UUID])])
elif test "$with_uuid" = e2fs ; then
  AC_CHECK_HEADERS(uuid/uuid.h,
    [AC_EGREP_HEADER([uuid_generate], uuid/uuid.h, [],
      [AC_MSG_ERROR([header file <uuid/uuid.h> does not match E2FS UUID library])])],
    [AC_CHECK_HEADERS(uuid.h,
      [AC_EGREP_HEADER([uuid_generate], uuid.h, [],
        [AC_MSG_ERROR([header file <uuid.h> does not match E2FS UUID library])])],
      [AC_MSG_ERROR([header file <uuid/uuid.h> or <uuid.h> is required for E2FS UUID])])])
elif test "$with_uuid" = ossp ; then
  AC_CHECK_HEADERS(ossp/uuid.h,
    [AC_EGREP_HEADER([uuid_export], ossp/uuid.h, [],
      [AC_MSG_ERROR([header file <ossp/uuid.h> does not match OSSP UUID library])])],
    [AC_CHECK_HEADERS(uuid.h,
      [AC_EGREP_HEADER([uuid_export], uuid.h, [],
        [AC_MSG_ERROR([header file <uuid.h> does not match OSSP UUID library])])],
      [AC_MSG_ERROR([header file <ossp/uuid.h> or <uuid.h> is required for OSSP UUID])])])
fi

if test "$PORTNAME" = "win32" ; then
   AC_CHECK_HEADERS(crtdefs.h)
fi

##
## Types, structures, compiler characteristics
##

m4_defun([AC_PROG_CC_STDC], []) dnl We don't want that.
AC_C_BIGENDIAN
AC_C_INLINE
PGAC_PRINTF_ARCHETYPE
AC_C_FLEXIBLE_ARRAY_MEMBER
PGAC_C_SIGNED
PGAC_C_FUNCNAME_SUPPORT
PGAC_C_STATIC_ASSERT
PGAC_C_TYPEOF
PGAC_C_TYPES_COMPATIBLE
PGAC_C_BUILTIN_BSWAP32
PGAC_C_BUILTIN_BSWAP64
PGAC_C_BUILTIN_CONSTANT_P
PGAC_C_BUILTIN_UNREACHABLE
PGAC_C_COMPUTED_GOTO
PGAC_C_VA_ARGS
PGAC_STRUCT_TIMEZONE
PGAC_UNION_SEMUN
PGAC_STRUCT_SOCKADDR_UN
PGAC_STRUCT_SOCKADDR_STORAGE
PGAC_STRUCT_SOCKADDR_STORAGE_MEMBERS
PGAC_STRUCT_ADDRINFO
AC_TYPE_INTPTR_T
AC_TYPE_UINTPTR_T
AC_TYPE_LONG_LONG_INT

PGAC_TYPE_LOCALE_T

AC_CHECK_TYPES([struct cmsgcred], [], [],
[#include <sys/socket.h>
#include <sys/param.h>
#ifdef HAVE_SYS_UCRED_H
#include <sys/ucred.h>
#endif])

AC_CHECK_TYPES([struct option], [], [],
[#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif])

if test "$with_zlib" = yes; then
  # Check that <zlib.h> defines z_streamp (versions before about 1.0.4
  # did not).  While we could work around the lack of z_streamp, it
  # seems unwise to encourage people to use such old zlib versions...
  AC_CHECK_TYPE(z_streamp, [], [AC_MSG_ERROR([zlib version is too old
Use --without-zlib to disable zlib support.])],
                [#include <zlib.h>])
fi

# On PPC, check if assembler supports LWARX instruction's mutex hint bit
case $host_cpu in
  ppc*|powerpc*)
    AC_MSG_CHECKING([whether assembler supports lwarx hint bit])
    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
	[int a = 0; int *p = &a; int r;
	 __asm__ __volatile__ (" lwarx %0,0,%1,1\n" : "=&r"(r) : "r"(p));])],
	[pgac_cv_have_ppc_mutex_hint=yes],
	[pgac_cv_have_ppc_mutex_hint=no])
    AC_MSG_RESULT([$pgac_cv_have_ppc_mutex_hint])
    if test x"$pgac_cv_have_ppc_mutex_hint" = xyes ; then
	AC_DEFINE(HAVE_PPC_LWARX_MUTEX_HINT, 1, [Define to 1 if the assembler supports PPC's LWARX mutex hint bit.])
    fi
  ;;
esac

# Check largefile support.  You might think this is a system service not a
# compiler characteristic, but you'd be wrong.  We must check this before
# probing existence of related functions such as fseeko, since the largefile
# defines can affect what is generated for that.
if test "$PORTNAME" != "win32"; then
   AC_SYS_LARGEFILE
   dnl Autoconf 2.69's AC_SYS_LARGEFILE believes it's a good idea to #define
   dnl _DARWIN_USE_64_BIT_INODE, but it isn't: on macOS 10.5 that activates a
   dnl bug that causes readdir() to sometimes return EINVAL.  On later macOS
   dnl versions where the feature actually works, it's on by default anyway.
   AH_VERBATIM([_DARWIN_USE_64_BIT_INODE],[])
fi

# Check for largefile support (must be after AC_SYS_LARGEFILE)
AC_CHECK_SIZEOF([off_t])

# If we don't have largefile support, can't handle segsize >= 2GB.
if test "$ac_cv_sizeof_off_t" -lt 8 -a "$segsize" != "1"; then
   AC_MSG_ERROR([Large file support is not enabled. Segment size cannot be larger than 1GB.])
fi


##
## Functions, global variables
##

PGAC_VAR_INT_TIMEZONE
AC_FUNC_ACCEPT_ARGTYPES
PGAC_FUNC_GETTIMEOFDAY_1ARG
PGAC_FUNC_WCSTOMBS_L

# Some versions of libedit contain strlcpy(), setproctitle(), and other
# symbols that that library has no business exposing to the world.  Pending
# acquisition of a clue by those developers, ignore libedit (including its
# possible alias of libreadline) while checking for everything else.
LIBS_including_readline="$LIBS"
LIBS=`echo "$LIBS" | sed -e 's/-ledit//g' -e 's/-lreadline//g'`

AC_CHECK_FUNCS([cbrt clock_gettime dlopen fdatasync getifaddrs getpeerucred getrlimit mbstowcs_l memmove poll pstat pthread_is_threaded_np readlink setproctitle setsid shm_open symlink sync_file_range towlower utime utimes wcstombs wcstombs_l])

AC_REPLACE_FUNCS(fseeko)
case $host_os in
	# NetBSD uses a custom fseeko/ftello built on fsetpos/fgetpos
	# Mingw uses macros to access Win32 API calls
	netbsd*|mingw*)
		AC_DEFINE(HAVE_FSEEKO, 1, [Define to 1 because replacement version used.])
		ac_cv_func_fseeko=yes;;
	*)
		AC_FUNC_FSEEKO;;
esac

# posix_fadvise() is a no-op on Solaris, so don't incur function overhead
# by calling it, 2009-04-02
# http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libc/port/gen/posix_fadvise.c
if test "$PORTNAME" != "solaris"; then
AC_CHECK_FUNCS(posix_fadvise)
AC_CHECK_DECLS(posix_fadvise, [], [], [#include <fcntl.h>])
fi

AC_CHECK_DECLS(fdatasync, [], [], [#include <unistd.h>])
AC_CHECK_DECLS([strlcat, strlcpy])
# This is probably only present on macOS, but may as well check always
AC_CHECK_DECLS(F_FULLFSYNC, [], [], [#include <fcntl.h>])

HAVE_IPV6=no
AC_CHECK_TYPE([struct sockaddr_in6],
        [AC_DEFINE(HAVE_IPV6, 1, [Define to 1 if you have support for IPv6.])
         HAVE_IPV6=yes],
        [],
[$ac_includes_default
#include <netinet/in.h>])
AC_SUBST(HAVE_IPV6)

AC_CACHE_CHECK([for PS_STRINGS], [pgac_cv_var_PS_STRINGS],
[AC_LINK_IFELSE([AC_LANG_PROGRAM(
[#include <machine/vmparam.h>
#include <sys/exec.h>
],
[PS_STRINGS->ps_nargvstr = 1;
PS_STRINGS->ps_argvstr = "foo";])],
[pgac_cv_var_PS_STRINGS=yes],
[pgac_cv_var_PS_STRINGS=no])])
if test "$pgac_cv_var_PS_STRINGS" = yes ; then
  AC_DEFINE([HAVE_PS_STRINGS], 1, [Define to 1 if the PS_STRINGS thing exists.])
fi


# We use our snprintf.c emulation if either snprintf() or vsnprintf()
# is missing.  Yes, there are machines that have only one.  We may
# also decide to use snprintf.c if snprintf() is present but does not
# have all the features we need --- see below.

if test "$PORTNAME" = "win32"; then
  # Win32 gets snprintf.c built unconditionally.
  #
  # To properly translate all NLS languages strings, we must support the
  # *printf() %$ format, which allows *printf() arguments to be selected
  # by position in the translated string.
  #
  # libintl versions < 0.13 use the native *printf() functions, and Win32
  # *printf() doesn't understand %$, so we must use our /port versions,
  # which do understand %$. libintl versions >= 0.13 include their own
  # *printf versions on Win32.  The libintl 0.13 release note text is:
  #
  #   C format strings with positions, as they arise when a translator
  #   needs to reorder a sentence, are now supported on all platforms.
  #   On those few platforms (NetBSD and Woe32) for which the native
  #   printf()/fprintf()/... functions don't support such format
  #   strings, replacements are provided through <libintl.h>.
  #
  # We could use libintl >= 0.13's *printf() if we were sure that we had
  # a litint >= 0.13 at runtime, but seeing that there is no clean way
  # to guarantee that, it is best to just use our own, so we are sure to
  # get %$ support. In include/port.h we disable the *printf() macros
  # that might have been defined by libintl.
  #
  # We do this unconditionally whether NLS is used or not so we are sure
  # that all Win32 libraries and binaries behave the same.
  pgac_need_repl_snprintf=yes
else
  pgac_need_repl_snprintf=no
  AC_CHECK_FUNCS(snprintf, [], pgac_need_repl_snprintf=yes)
  AC_CHECK_FUNCS(vsnprintf, [], pgac_need_repl_snprintf=yes)
fi


# Check whether <stdio.h> declares snprintf() and vsnprintf(); if not,
# include/c.h will provide declarations.  Note this is a separate test
# from whether the functions exist in the C library --- there are
# systems that have the functions but don't bother to declare them :-(

AC_CHECK_DECLS([snprintf, vsnprintf])


dnl Cannot use AC_CHECK_FUNC because isinf may be a macro
AC_CACHE_CHECK([for isinf], ac_cv_func_isinf,
[AC_LINK_IFELSE([AC_LANG_PROGRAM([
#include <math.h>
double glob_double;
],
[return isinf(glob_double) ? 0 : 1;])],
[ac_cv_func_isinf=yes],
[ac_cv_func_isinf=no])])

if test $ac_cv_func_isinf = yes ; then
  AC_DEFINE(HAVE_ISINF, 1, [Define to 1 if you have isinf().])
else
  AC_LIBOBJ(isinf)
  # Look for a way to implement a substitute for isinf()
  AC_CHECK_FUNCS([fpclass fp_class fp_class_d class], [break])
fi

AC_REPLACE_FUNCS([crypt fls getopt getrusage inet_aton mkdtemp random rint srandom strerror strlcat strlcpy])

case $host_os in

        # Windows uses a specialised env handler
        # and doesn't need a replacement getpeereid because it doesn't use
        # Unix sockets.
        mingw*)
                AC_DEFINE(HAVE_UNSETENV, 1, [Define to 1 because replacement version used.])
                AC_DEFINE(HAVE_GETPEEREID, 1, [Define to 1 because function not required.])
                ac_cv_func_unsetenv=yes
                ac_cv_func_getpeereid=yes;;
        *)
                AC_REPLACE_FUNCS([unsetenv getpeereid])
		;;
esac

# System's version of getaddrinfo(), if any, may be used only if we found
# a definition for struct addrinfo; see notes in src/include/getaddrinfo.h.
# We use only our own getaddrinfo.c on Windows, but it's time to revisit that.
if test x"$ac_cv_type_struct_addrinfo" = xyes && \
   test "$PORTNAME" != "win32"; then
  AC_REPLACE_FUNCS([getaddrinfo])
else
  AC_LIBOBJ(getaddrinfo)
fi

# Similarly, use system's getopt_long() only if system provides struct option.
if test x"$ac_cv_type_struct_option" = xyes ; then
  AC_REPLACE_FUNCS([getopt_long])
else
  AC_LIBOBJ(getopt_long)
fi

# Solaris' getopt() doesn't do what we want for long options, so always use
# our version on that platform.
if test "$PORTNAME" = "solaris"; then
  AC_LIBOBJ(getopt)
fi

# mingw has adopted a GNU-centric interpretation of optind/optreset,
# so always use our version on Windows.
if test "$PORTNAME" = "win32"; then
  AC_LIBOBJ(getopt)
  AC_LIBOBJ(getopt_long)
fi

# Win32 (really MinGW) support
if test "$PORTNAME" = "win32"; then
  AC_REPLACE_FUNCS(gettimeofday)
  AC_LIBOBJ(dirmod)
  AC_LIBOBJ(kill)
  AC_LIBOBJ(open)
  AC_LIBOBJ(system)
  AC_LIBOBJ(win32env)
  AC_LIBOBJ(win32error)
  AC_LIBOBJ(win32security)
  AC_LIBOBJ(win32setlocale)
  AC_DEFINE([HAVE_SYMLINK], 1,
            [Define to 1 if you have the `symlink' function.])
  AC_CHECK_TYPES(MINIDUMP_TYPE, [pgac_minidump_type=yes], [pgac_minidump_type=no], [
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <string.h>
#include <dbghelp.h>])
fi
if test x"$pgac_minidump_type" = x"yes" ; then
  AC_SUBST(have_win32_dbghelp,yes)
else
  AC_SUBST(have_win32_dbghelp,no)
fi

# Cygwin needs only a bit of that
if test "$PORTNAME" = "cygwin"; then
  AC_LIBOBJ(dirmod)
fi

AC_CHECK_DECLS([sys_siglist], [], [],
[#include <signal.h>
/* NetBSD declares sys_siglist in unistd.h.  */
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
])

AC_CHECK_FUNC(syslog,
              [AC_CHECK_HEADER(syslog.h,
                               [AC_DEFINE(HAVE_SYSLOG, 1, [Define to 1 if you have the syslog interface.])])])

AC_CACHE_CHECK([for opterr], pgac_cv_var_int_opterr,
[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <unistd.h>],
  [extern int opterr; opterr = 1;])],
  [pgac_cv_var_int_opterr=yes],
  [pgac_cv_var_int_opterr=no])])
if test x"$pgac_cv_var_int_opterr" = x"yes"; then
  AC_DEFINE(HAVE_INT_OPTERR, 1, [Define to 1 if you have the global variable 'int opterr'.])
fi

AC_CACHE_CHECK([for optreset], pgac_cv_var_int_optreset,
[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <unistd.h>],
  [extern int optreset; optreset = 1;])],
  [pgac_cv_var_int_optreset=yes],
  [pgac_cv_var_int_optreset=no])])
if test x"$pgac_cv_var_int_optreset" = x"yes"; then
  AC_DEFINE(HAVE_INT_OPTRESET, 1, [Define to 1 if you have the global variable 'int optreset'.])
fi

AC_CHECK_FUNCS([strtoll strtoq], [break])
AC_CHECK_FUNCS([strtoull strtouq], [break])

if test "$with_icu" = yes; then
  # ICU functions are macros, so we need to do this the long way.

  # ucol_strcollUTF8() appeared in ICU 50.
  AC_CACHE_CHECK([for ucol_strcollUTF8], [pgac_cv_func_ucol_strcollUTF8],
[ac_save_CPPFLAGS=$CPPFLAGS
CPPFLAGS="$ICU_CFLAGS $CPPFLAGS"
ac_save_LIBS=$LIBS
LIBS="$ICU_LIBS $LIBS"
AC_LINK_IFELSE([AC_LANG_PROGRAM(
[#include <unicode/ucol.h>
],
[ucol_strcollUTF8(NULL, NULL, 0, NULL, 0, NULL);])],
[pgac_cv_func_ucol_strcollUTF8=yes],
[pgac_cv_func_ucol_strcollUTF8=no])
CPPFLAGS=$ac_save_CPPFLAGS
LIBS=$ac_save_LIBS])
  if test "$pgac_cv_func_ucol_strcollUTF8" = yes ; then
    AC_DEFINE([HAVE_UCOL_STRCOLLUTF8], 1, [Define to 1 if you have the `ucol_strcollUTF8' function.])
  fi
fi

# Lastly, restore full LIBS list and check for readline/libedit symbols
LIBS="$LIBS_including_readline"

if test "$with_readline" = yes; then
  PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
  AC_CHECK_FUNCS([rl_completion_matches rl_filename_completion_function rl_reset_screen_size])
  AC_CHECK_FUNCS([append_history history_truncate_file])
fi


# This test makes sure that run tests work at all.  Sometimes a shared
# library is found by the linker, but the runtime linker can't find it.
# This check should come after all modifications of compiler or linker
# variables, and before any other run tests.
AC_MSG_CHECKING([test program])
AC_RUN_IFELSE([AC_LANG_SOURCE([int main() { return 0; }])],
[AC_MSG_RESULT(ok)],
[AC_MSG_RESULT(failed)
AC_MSG_ERROR([[
Could not execute a simple test program.  This may be a problem
related to locating shared libraries.  Check the file 'config.log'
for the exact reason.]])],
[AC_MSG_RESULT([cross-compiling])])

# --------------------
# Run tests below here
# --------------------

# Force use of our snprintf if system's doesn't do arg control
# See comment above at snprintf test for details.
if test "$enable_nls" = yes -a "$pgac_need_repl_snprintf" = no; then
  PGAC_FUNC_SNPRINTF_ARG_CONTROL
  if test $pgac_cv_snprintf_arg_control != yes ; then
    pgac_need_repl_snprintf=yes
  fi
fi


dnl Check to see if we have a working 64-bit integer type.
dnl This breaks down into two steps:
dnl (1) figure out if the compiler has a 64-bit int type with working
dnl arithmetic, and if so
dnl (2) see whether snprintf() can format the type correctly.  (Currently,
dnl snprintf is the only library routine we really need for int8 support.)
dnl It's entirely possible to have a compiler that handles a 64-bit type
dnl when the C library doesn't; this is fairly likely when using gcc on
dnl an older platform, for example.
dnl If there is no native snprintf() or it does not handle the 64-bit type,
dnl we force our own version of snprintf() to be used instead.
dnl Note this test must be run after our initial check for snprintf/vsnprintf.

dnl As of Postgres 8.4, we no longer support compilers without a working
dnl 64-bit type.  But we still handle the case of snprintf being broken.

PGAC_TYPE_64BIT_INT([long int])

if test x"$HAVE_LONG_INT_64" = x"yes" ; then
  pg_int64_type="long int"
else
  PGAC_TYPE_64BIT_INT([long long int])
  if test x"$HAVE_LONG_LONG_INT_64" = x"yes" ; then
    pg_int64_type="long long int"
  else
    AC_MSG_ERROR([Cannot find a working 64-bit integer type.])
  fi
fi

AC_DEFINE_UNQUOTED(PG_INT64_TYPE, $pg_int64_type,
  [Define to the name of a signed 64-bit integer type.])

dnl If we need to use "long long int", figure out whether nnnLL notation works.

if test x"$HAVE_LONG_LONG_INT_64" = xyes ; then
  AC_COMPILE_IFELSE([AC_LANG_SOURCE([
#define INT64CONST(x)  x##LL
long long int foo = INT64CONST(0x1234567890123456);
])],
	[AC_DEFINE(HAVE_LL_CONSTANTS, 1, [Define to 1 if constants of type 'long long int' should have the suffix LL.])],
	[])
fi


# If we found "long int" is 64 bits, assume snprintf handles it.  If
# we found we need to use "long long int", better check.  We cope with
# snprintfs that use %lld, %qd, or %I64d as the format.  If none of these
# work, fall back to our own snprintf emulation (which we know uses %lld).

if test "$HAVE_LONG_LONG_INT_64" = yes ; then
  if test $pgac_need_repl_snprintf = no; then
    PGAC_FUNC_SNPRINTF_LONG_LONG_INT_MODIFIER
    if test "$LONG_LONG_INT_MODIFIER" = ""; then
      # Force usage of our own snprintf, since system snprintf is broken
      pgac_need_repl_snprintf=yes
      LONG_LONG_INT_MODIFIER='ll'
    fi
  else
    # Here if we previously decided we needed to use our own snprintf
    LONG_LONG_INT_MODIFIER='ll'
  fi
else
  # Here if we are not using 'long long int' at all
  LONG_LONG_INT_MODIFIER='l'
fi

INT64_MODIFIER="\"$LONG_LONG_INT_MODIFIER\""

AC_DEFINE_UNQUOTED(INT64_MODIFIER, $INT64_MODIFIER,
                   [Define to the appropriate snprintf length modifier for 64-bit ints.])

# Also force use of our snprintf if the system's doesn't support the %z flag.
if test "$pgac_need_repl_snprintf" = no; then
  PGAC_FUNC_SNPRINTF_SIZE_T_SUPPORT
  if test "$pgac_cv_snprintf_size_t_support" != yes; then
    pgac_need_repl_snprintf=yes
  fi
fi

# Now we have checked all the reasons to replace snprintf
if test $pgac_need_repl_snprintf = yes; then
  AC_DEFINE(USE_REPL_SNPRINTF, 1, [Use replacement snprintf() functions.])
  AC_LIBOBJ(snprintf)
fi

# Check size of void *, size_t (enables tweaks for > 32bit address space)
AC_CHECK_SIZEOF([void *])
AC_CHECK_SIZEOF([size_t])
AC_CHECK_SIZEOF([long])

# Decide whether float4 is passed by value: user-selectable, enabled by default
AC_MSG_CHECKING([whether to build with float4 passed by value])
PGAC_ARG_BOOL(enable, float4-byval, yes, [disable float4 passed by value],
              [AC_DEFINE([USE_FLOAT4_BYVAL], 1,
                         [Define to 1 if you want float4 values to be passed by value. (--enable-float4-byval)])
               float4passbyval=true],
              [float4passbyval=false])
AC_MSG_RESULT([$enable_float4_byval])
AC_DEFINE_UNQUOTED([FLOAT4PASSBYVAL], [$float4passbyval], [float4 values are passed by value if 'true', by reference if 'false'])

# Decide whether float8 is passed by value.
# Note: this setting also controls int8 and related types such as timestamp.
# If sizeof(Datum) >= 8, this is user-selectable, enabled by default.
# If not, trying to select it is an error.
AC_MSG_CHECKING([whether to build with float8 passed by value])
if test $ac_cv_sizeof_void_p -ge 8 ; then
  PGAC_ARG_BOOL(enable, float8-byval, yes, [disable float8 passed by value])
else
  PGAC_ARG_BOOL(enable, float8-byval, no, [disable float8 passed by value])
  if test "$enable_float8_byval" = yes ; then
    AC_MSG_ERROR([--enable-float8-byval is not supported on 32-bit platforms.])
  fi
fi
if test "$enable_float8_byval" = yes ; then
  AC_DEFINE([USE_FLOAT8_BYVAL], 1,
            [Define to 1 if you want float8, int8, etc values to be passed by value. (--enable-float8-byval)])
  float8passbyval=true
else
  float8passbyval=false
fi
AC_MSG_RESULT([$enable_float8_byval])
AC_DEFINE_UNQUOTED([FLOAT8PASSBYVAL], [$float8passbyval], [float8, int8, and related values are passed by value if 'true', by reference if 'false'])

# Determine memory alignment requirements for the basic C data types.

AC_CHECK_ALIGNOF(short)
AC_CHECK_ALIGNOF(int)
AC_CHECK_ALIGNOF(long)
if test x"$HAVE_LONG_LONG_INT_64" = x"yes" ; then
  AC_CHECK_ALIGNOF(long long int)
fi
AC_CHECK_ALIGNOF(double)

# Compute maximum alignment of any basic type.
# We assume long's alignment is at least as strong as char, short, or int;
# but we must check long long (if it exists) and double.

MAX_ALIGNOF=$ac_cv_alignof_long
if test $MAX_ALIGNOF -lt $ac_cv_alignof_double ; then
  MAX_ALIGNOF=$ac_cv_alignof_double
fi
if test x"$HAVE_LONG_LONG_INT_64" = xyes && test $MAX_ALIGNOF -lt $ac_cv_alignof_long_long_int ; then
  MAX_ALIGNOF="$ac_cv_alignof_long_long_int"
fi
AC_DEFINE_UNQUOTED(MAXIMUM_ALIGNOF, $MAX_ALIGNOF, [Define as the maximum alignment requirement of any C data type.])


# Some platforms predefine the types int8, int16, etc.  Only check
# a (hopefully) representative subset.
AC_CHECK_TYPES([int8, uint8, int64, uint64], [], [],
[#include <stdio.h>])

# Check for extensions offering the integer scalar type __int128.
PGAC_TYPE_128BIT_INT

# Check for various atomic operations now that we have checked how to declare
# 64bit integers.
PGAC_HAVE_GCC__SYNC_CHAR_TAS
PGAC_HAVE_GCC__SYNC_INT32_TAS
PGAC_HAVE_GCC__SYNC_INT32_CAS
PGAC_HAVE_GCC__SYNC_INT64_CAS
PGAC_HAVE_GCC__ATOMIC_INT32_CAS
PGAC_HAVE_GCC__ATOMIC_INT64_CAS


# Check for x86 cpuid instruction
AC_CACHE_CHECK([for __get_cpuid], [pgac_cv__get_cpuid],
[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <cpuid.h>],
  [[unsigned int exx[4] = {0, 0, 0, 0};
  __get_cpuid(1, &exx[0], &exx[1], &exx[2], &exx[3]);
  ]])],
  [pgac_cv__get_cpuid="yes"],
  [pgac_cv__get_cpuid="no"])])
if test x"$pgac_cv__get_cpuid" = x"yes"; then
  AC_DEFINE(HAVE__GET_CPUID, 1, [Define to 1 if you have __get_cpuid.])
fi

AC_CACHE_CHECK([for __cpuid], [pgac_cv__cpuid],
[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <intrin.h>],
  [[unsigned int exx[4] = {0, 0, 0, 0};
  __get_cpuid(exx[0], 1);
  ]])],
  [pgac_cv__cpuid="yes"],
  [pgac_cv__cpuid="no"])])
if test x"$pgac_cv__cpuid" = x"yes"; then
  AC_DEFINE(HAVE__CPUID, 1, [Define to 1 if you have __cpuid.])
fi

# Check for Intel SSE 4.2 intrinsics to do CRC calculations.
#
# First check if the _mm_crc32_u8 and _mm_crc32_u64 intrinsics can be used
# with the default compiler flags. If not, check if adding the -msse4.2
# flag helps. CFLAGS_SSE42 is set to -msse4.2 if that's required.
PGAC_SSE42_CRC32_INTRINSICS([])
if test x"$pgac_sse42_crc32_intrinsics" != x"yes"; then
  PGAC_SSE42_CRC32_INTRINSICS([-msse4.2])
fi
AC_SUBST(CFLAGS_SSE42)

# Are we targeting a processor that supports SSE 4.2? gcc, clang and icc all
# define __SSE4_2__ in that case.
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [
#ifndef __SSE4_2__
#error __SSE4_2__ not defined
#endif
])], [SSE4_2_TARGETED=1])

# Select CRC-32C implementation.
#
# If we are targeting a processor that has SSE 4.2 instructions, we can use the
# special CRC instructions for calculating CRC-32C. If we're not targeting such
# a processor, but we can nevertheless produce code that uses the SSE
# intrinsics, perhaps with some extra CFLAGS, compile both implementations and
# select which one to use at runtime, depending on whether SSE 4.2 is supported
# by the processor we're running on.
#
# You can override this logic by setting the appropriate USE_*_CRC32 flag to 1
# in the template or configure command line.
if test x"$USE_SSE42_CRC32C" = x"" && test x"$USE_SSE42_CRC32C_WITH_RUNTIME_CHECK" = x"" && test x"$USE_SLICING_BY_8_CRC32C" = x""; then
  if test x"$pgac_sse42_crc32_intrinsics" = x"yes" && test x"$SSE4_2_TARGETED" = x"1" ; then
    USE_SSE42_CRC32C=1
  else
    # the CPUID instruction is needed for the runtime check.
    if test x"$pgac_sse42_crc32_intrinsics" = x"yes" && (test x"$pgac_cv__get_cpuid" = x"yes" || test x"$pgac_cv__cpuid" = x"yes"); then
      USE_SSE42_CRC32C_WITH_RUNTIME_CHECK=1
    else
      # fall back to slicing-by-8 algorithm which doesn't require any special
      # CPU support.
      USE_SLICING_BY_8_CRC32C=1
    fi
  fi
fi

# Set PG_CRC32C_OBJS appropriately depending on the selected implementation.
AC_MSG_CHECKING([which CRC-32C implementation to use])
if test x"$USE_SSE42_CRC32C" = x"1"; then
  AC_DEFINE(USE_SSE42_CRC32C, 1, [Define to 1 use Intel SSE 4.2 CRC instructions.])
  PG_CRC32C_OBJS="pg_crc32c_sse42.o"
  AC_MSG_RESULT(SSE 4.2)
else
  if test x"$USE_SSE42_CRC32C_WITH_RUNTIME_CHECK" = x"1"; then
    AC_DEFINE(USE_SSE42_CRC32C_WITH_RUNTIME_CHECK, 1, [Define to 1 to use Intel SSSE 4.2 CRC instructions with a runtime check.])
    PG_CRC32C_OBJS="pg_crc32c_sse42.o pg_crc32c_sb8.o pg_crc32c_choose.o"
    AC_MSG_RESULT(SSE 4.2 with runtime check)
  else
    AC_DEFINE(USE_SLICING_BY_8_CRC32C, 1, [Define to 1 to use Intel SSE 4.2 CRC instructions with a runtime check.])
    PG_CRC32C_OBJS="pg_crc32c_sb8.o"
    AC_MSG_RESULT(slicing-by-8)
  fi
fi
AC_SUBST(PG_CRC32C_OBJS)


# Select semaphore implementation type.
if test "$PORTNAME" != "win32"; then
  if test x"$PREFERRED_SEMAPHORES" = x"NAMED_POSIX" ; then
    # Need sem_open for this
    AC_SEARCH_LIBS(sem_open, [rt pthread], [USE_NAMED_POSIX_SEMAPHORES=1])
  fi
  if test x"$PREFERRED_SEMAPHORES" = x"UNNAMED_POSIX" ; then
    # Need sem_init for this
    AC_SEARCH_LIBS(sem_init, [rt pthread], [USE_UNNAMED_POSIX_SEMAPHORES=1])
  fi
  AC_MSG_CHECKING([which semaphore API to use])
  if test x"$USE_NAMED_POSIX_SEMAPHORES" = x"1" ; then
    AC_DEFINE(USE_NAMED_POSIX_SEMAPHORES, 1, [Define to select named POSIX semaphores.])
    SEMA_IMPLEMENTATION="src/backend/port/posix_sema.c"
    sematype="named POSIX"
  else
    if test x"$USE_UNNAMED_POSIX_SEMAPHORES" = x"1" ; then
      AC_DEFINE(USE_UNNAMED_POSIX_SEMAPHORES, 1, [Define to select unnamed POSIX semaphores.])
      SEMA_IMPLEMENTATION="src/backend/port/posix_sema.c"
      sematype="unnamed POSIX"
    else
      AC_DEFINE(USE_SYSV_SEMAPHORES, 1, [Define to select SysV-style semaphores.])
      SEMA_IMPLEMENTATION="src/backend/port/sysv_sema.c"
      sematype="System V"
    fi
  fi
  AC_MSG_RESULT([$sematype])
else
  AC_DEFINE(USE_WIN32_SEMAPHORES, 1, [Define to select Win32-style semaphores.])
  SEMA_IMPLEMENTATION="src/backend/port/win32_sema.c"
fi


# Select shared-memory implementation type.
if test "$PORTNAME" != "win32"; then
  AC_DEFINE(USE_SYSV_SHARED_MEMORY, 1, [Define to select SysV-style shared memory.])
  SHMEM_IMPLEMENTATION="src/backend/port/sysv_shmem.c"
else
  AC_DEFINE(USE_WIN32_SHARED_MEMORY, 1, [Define to select Win32-style shared memory.])
  SHMEM_IMPLEMENTATION="src/backend/port/win32_shmem.c"
fi

# Select random number source
#
# You can override this logic by setting the appropriate USE_*RANDOM flag to 1
# in the template or configure command line.

# If not selected manually, try to select a source automatically.
if test "$enable_strong_random" = "yes" && test x"$USE_OPENSSL_RANDOM" = x"" && test x"$USE_WIN32_RANDOM" = x"" && test x"$USE_DEV_URANDOM" = x"" ; then
  if test x"$with_openssl" = x"yes" ; then
    USE_OPENSSL_RANDOM=1
  elif test "$PORTNAME" = "win32" ; then
    USE_WIN32_RANDOM=1
  else
    AC_CHECK_FILE([/dev/urandom], [], [])

    if test x"$ac_cv_file__dev_urandom" = x"yes" ; then
      USE_DEV_URANDOM=1
    fi
  fi
fi

AC_MSG_CHECKING([which random number source to use])
if test "$enable_strong_random" = yes ; then
  if test x"$USE_OPENSSL_RANDOM" = x"1" ; then
    AC_DEFINE(USE_OPENSSL_RANDOM, 1, [Define to use OpenSSL for random number generation])
    AC_MSG_RESULT([OpenSSL])
  elif test x"$USE_WIN32_RANDOM" = x"1" ; then
    AC_DEFINE(USE_WIN32_RANDOM, 1, [Define to use native Windows API for random number generation])
    AC_MSG_RESULT([Windows native])
  elif test x"$USE_DEV_URANDOM" = x"1" ; then
    AC_DEFINE(USE_DEV_URANDOM, 1, [Define to use /dev/urandom for random number generation])
    AC_MSG_RESULT([/dev/urandom])
  else
    AC_MSG_ERROR([
no source of strong random numbers was found
PostgreSQL can use OpenSSL or /dev/urandom as a source of random numbers,
for authentication protocols. You can use --disable-strong-random to use a
built-in pseudo random number generator, but that may be insecure.])
  fi
  AC_DEFINE(HAVE_STRONG_RANDOM, 1, [Define to use have a strong random number source])
else
    AC_MSG_RESULT([weak builtin PRNG])
    AC_MSG_WARN([
*** Not using a strong random number source may be insecure.])
fi

# If not set in template file, set bytes to use libc memset()
if test x"$MEMSET_LOOP_LIMIT" = x"" ; then
  MEMSET_LOOP_LIMIT=1024
fi
AC_DEFINE_UNQUOTED(MEMSET_LOOP_LIMIT, ${MEMSET_LOOP_LIMIT}, [Define bytes to use libc memset().])


if test "$enable_nls" = yes ; then
  PGAC_CHECK_GETTEXT
fi

# Check for Tcl configuration script tclConfig.sh
if test "$with_tcl" = yes; then
    PGAC_PATH_TCLCONFIGSH([$with_tclconfig])
    PGAC_EVAL_TCLCONFIGSH([$TCL_CONFIG_SH],
                          [TCL_INCLUDE_SPEC,TCL_LIBS,TCL_LIB_SPEC,TCL_SHARED_BUILD])
    AC_SUBST(TCL_SHLIB_LD_LIBS)dnl don't want to double-evaluate that one
    if test "$TCL_SHARED_BUILD" != 1; then
      AC_MSG_ERROR([cannot build PL/Tcl because Tcl is not a shared library
Use --without-tcl to disable building PL/Tcl.])
    fi
    # now that we have TCL_INCLUDE_SPEC, we can check for <tcl.h>
    ac_save_CPPFLAGS=$CPPFLAGS
    CPPFLAGS="$TCL_INCLUDE_SPEC $CPPFLAGS"
    AC_CHECK_HEADER(tcl.h, [], [AC_MSG_ERROR([header file <tcl.h> is required for Tcl])])
    CPPFLAGS=$ac_save_CPPFLAGS
fi

# check for <perl.h>
if test "$with_perl" = yes; then
  ac_save_CPPFLAGS=$CPPFLAGS
  CPPFLAGS="$CPPFLAGS -I$perl_archlibexp/CORE"
  AC_CHECK_HEADER(perl.h, [], [AC_MSG_ERROR([header file <perl.h> is required for Perl])],
                  [#include <EXTERN.h>])
  # While we're at it, check that we can link to libperl.
  # On most platforms, if perl.h is there then libperl.so will be too, but at
  # this writing Debian packages them separately.  There is no known reason to
  # waste cycles on separate probes for the Tcl or Python libraries, though.
  pgac_save_LIBS=$LIBS
  LIBS="$perl_embed_ldflags"
  AC_MSG_CHECKING([for libperl])
  AC_LINK_IFELSE([AC_LANG_PROGRAM([
#include <EXTERN.h>
#include <perl.h>
],  [perl_alloc();])],
    [AC_MSG_RESULT(yes)],
    [AC_MSG_RESULT(no)
     AC_MSG_ERROR([libperl library is required for Perl])])
  LIBS=$pgac_save_LIBS
  CPPFLAGS=$ac_save_CPPFLAGS
fi

# check for <Python.h>
if test "$with_python" = yes; then
  ac_save_CPPFLAGS=$CPPFLAGS
  CPPFLAGS="$python_includespec $CPPFLAGS"
  AC_CHECK_HEADER(Python.h, [], [AC_MSG_ERROR([header file <Python.h> is required for Python])])
  CPPFLAGS=$ac_save_CPPFLAGS
fi

#
# Check for DocBook and tools
#
PGAC_PROG_NSGMLS
PGAC_CHECK_DOCBOOK(4.2)
AC_CHECK_PROGS(DBTOEPUB, dbtoepub)
AC_CHECK_PROGS(XMLLINT, xmllint)
AC_CHECK_PROGS(XSLTPROC, xsltproc)
AC_CHECK_PROGS(OSX, [osx sgml2xml sx])
AC_CHECK_PROGS(FOP, fop)

#
# Check for test tools
#
if test "$enable_tap_tests" = yes; then
  AC_CHECK_PROGS(PROVE, prove)
  if test -z "$PROVE"; then
    AC_MSG_ERROR([prove not found])
  fi
  if test -z "$PERL"; then
    AC_MSG_ERROR([Perl not found])
  fi
fi

# Thread testing

# We have to run the thread test near the end so we have all our symbols
# defined.  Cross compiling throws a warning.
#
if test "$enable_thread_safety" = yes; then
if test "$PORTNAME" != "win32"
then
AC_MSG_CHECKING([thread safety of required library functions])

_CFLAGS="$CFLAGS"
_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS -DIN_CONFIGURE"
LIBS="$LIBS $PTHREAD_LIBS"
AC_RUN_IFELSE(
  [AC_LANG_SOURCE([[#include "$srcdir/src/test/thread/thread_test.c"]])],
  [AC_MSG_RESULT(yes)],
  [AC_MSG_RESULT(no)
  AC_MSG_ERROR([thread test program failed
This platform is not thread-safe.  Check the file 'config.log' or compile
and run src/test/thread/thread_test for the exact reason.
Use --disable-thread-safety to disable thread safety.])],
  [AC_MSG_RESULT(maybe)
  AC_MSG_WARN([
*** Skipping thread test program because of cross-compile build.
*** Run the program in src/test/thread on the target machine.
])])
CFLAGS="$_CFLAGS"
LIBS="$_LIBS"
else
AC_MSG_WARN([*** skipping thread test on Win32])
fi
fi

# If compiler will take -Wl,--as-needed (or various platform-specific
# spellings thereof) then add that to LDFLAGS.  This is much easier than
# trying to filter LIBS to the minimum for each executable.
# On (at least) some Red-Hat-derived systems, this switch breaks linking to
# libreadline; therefore we postpone testing it until we know what library
# dependencies readline has.  The test code will try to link with $LIBS.
if test "$with_readline" = yes; then
  link_test_func=readline
else
  link_test_func=exit
fi

if test "$PORTNAME" = "darwin"; then
  PGAC_PROG_CC_LDFLAGS_OPT([-Wl,-dead_strip_dylibs], $link_test_func)
elif test "$PORTNAME" = "openbsd"; then
  PGAC_PROG_CC_LDFLAGS_OPT([-Wl,-Bdynamic], $link_test_func)
else
  PGAC_PROG_CC_LDFLAGS_OPT([-Wl,--as-needed], $link_test_func)
fi

# Create compiler version string
if test x"$GCC" = x"yes" ; then
  cc_string=`${CC} --version | sed q`
  case $cc_string in [[A-Za-z]]*) ;; *) cc_string="GCC $cc_string";; esac
elif test x"$SUN_STUDIO_CC" = x"yes" ; then
  cc_string=`${CC} -V 2>&1 | sed q`
else
  cc_string=$CC
fi

AC_DEFINE_UNQUOTED(PG_VERSION_STR,
                   ["PostgreSQL $PG_VERSION on $host, compiled by $cc_string, `expr $ac_cv_sizeof_void_p \* 8`-bit"],
                   [A string containing the version number, platform, and C compiler])

# Supply a numeric version string for use by 3rd party add-ons
# awk -F is a regex on some platforms, and not on others, so make "." a tab
[PG_VERSION_NUM="`echo "$PACKAGE_VERSION" | sed 's/[A-Za-z].*$//' |
tr '.' '	' |
$AWK '{printf "%d%02d%02d", $1, $2, (NF >= 3) ? $3 : 0}'`"]
AC_DEFINE_UNQUOTED(PG_VERSION_NUM, $PG_VERSION_NUM, [PostgreSQL version as a number])
AC_SUBST(PG_VERSION_NUM)


# Begin output steps

AC_MSG_NOTICE([using compiler=$cc_string])
AC_MSG_NOTICE([using CFLAGS=$CFLAGS])
AC_MSG_NOTICE([using CPPFLAGS=$CPPFLAGS])
AC_MSG_NOTICE([using LDFLAGS=$LDFLAGS])

# prepare build tree if outside source tree
# Note 1: test -ef might not exist, but it's more reliable than `pwd`.
# Note 2: /bin/pwd might be better than shell's built-in at getting
#         a symlink-free name.
if ( test "$srcdir" -ef . ) >/dev/null 2>&1 || test "`cd $srcdir && /bin/pwd`" = "`/bin/pwd`"; then
  vpath_build=no
else
  vpath_build=yes
  if test "$no_create" != yes; then
    _AS_ECHO_N([preparing build tree... ])
    pgac_abs_top_srcdir=`cd "$srcdir" && pwd`
    $SHELL "$ac_aux_dir/prep_buildtree" "$pgac_abs_top_srcdir" "." \
      || AC_MSG_ERROR(failed)
    AC_MSG_RESULT(done)
  fi
fi
AC_SUBST(vpath_build)


AC_CONFIG_FILES([GNUmakefile src/Makefile.global])

AC_CONFIG_LINKS([
  src/backend/port/dynloader.c:src/backend/port/dynloader/${template}.c
  src/backend/port/pg_sema.c:${SEMA_IMPLEMENTATION}
  src/backend/port/pg_shmem.c:${SHMEM_IMPLEMENTATION}
  src/include/dynloader.h:src/backend/port/dynloader/${template}.h
  src/include/pg_config_os.h:src/include/port/${template}.h
  src/Makefile.port:src/makefiles/Makefile.${template}
])

if test "$PORTNAME" = "win32"; then
AC_CONFIG_COMMANDS([check_win32_symlinks],[
# Links sometimes fail undetected on Mingw -
# so here we detect it and warn the user
for FILE in $CONFIG_LINKS
 do
	# test -e works for symlinks in the MinGW console
	test -e `expr "$FILE" : '\([[^:]]*\)'` || AC_MSG_WARN([*** link for $FILE -- please fix by hand])
 done
])
fi

AC_CONFIG_HEADERS([src/include/pg_config.h],
[
# Update timestamp for pg_config.h (see Makefile.global)
echo >src/include/stamp-h
])

AC_CONFIG_HEADERS([src/include/pg_config_ext.h],
[
# Update timestamp for pg_config_ext.h (see Makefile.global)
echo >src/include/stamp-ext-h
])

AC_CONFIG_HEADERS([src/interfaces/ecpg/include/ecpg_config.h],
                  [echo >src/interfaces/ecpg/include/stamp-h])

AC_OUTPUT