xz/configure.ac

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# -*- Autoconf -*-
# SPDX-License-Identifier: 0BSD
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###############################################################################
#
# Process this file with autoconf to produce a configure script.
#
# Author: Lasse Collin
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#
###############################################################################
# NOTE: Don't add useless checks. autoscan detects this and that, but don't
# let it confuse you. For example, we don't care about checking for behavior
# of malloc(), stat(), or lstat(), since we don't use those functions in
# a way that would cause the problems the autoconf macros check.
AC_PREREQ([2.69])
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2010-09-28 07:59:53 +00:00
AC_INIT([XZ Utils], m4_esyscmd([/bin/sh build-aux/version.sh]),
[xz@tukaani.org], [xz], [https://tukaani.org/xz/])
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AC_CONFIG_SRCDIR([src/liblzma/common/common.h])
AC_CONFIG_AUX_DIR([build-aux])
AC_CONFIG_MACRO_DIR([m4])
AC_CONFIG_HEADERS([config.h])
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echo
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echo "$PACKAGE_STRING"
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echo
echo "System type:"
# This is needed to know if assembler optimizations can be used.
AC_CANONICAL_HOST
# We do some special things on Windows (32-bit or 64-bit) builds.
case $host_os in
mingw* | cygwin | msys) is_w32=yes ;;
*) is_w32=no ;;
esac
AM_CONDITIONAL([COND_W32], [test "$is_w32" = yes])
# We need to use $EXEEXT with $(LN_S) when creating symlinks to
# executables. Cygwin is an exception to this, since it is recommended
# that symlinks don't have the .exe suffix. To make this work, we
# define LN_EXEEXT.
#
# MSYS2 is treated the same way as Cygwin. It uses plain "msys" like
# the original MSYS when building MSYS/MSYS2-binaries. Hopefully this
# doesn't break things for the original MSYS developers. Note that this
# doesn't affect normal MSYS/MSYS2 users building non-MSYS/MSYS2 binaries
# since in that case the $host_os is usually mingw32.
case $host_os in
cygwin | msys) LN_EXEEXT= ;;
*) LN_EXEEXT='$(EXEEXT)' ;;
esac
AC_SUBST([LN_EXEEXT])
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echo
echo "Configure options:"
AM_CFLAGS=
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#############
# Debugging #
#############
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AC_MSG_CHECKING([if debugging code should be compiled])
AC_ARG_ENABLE([debug], AS_HELP_STRING([--enable-debug], [Enable debugging code.]),
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[], enable_debug=no)
if test "x$enable_debug" = xyes; then
AC_MSG_RESULT([yes])
else
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AC_DEFINE([NDEBUG], [1], [Define to 1 to disable debugging code.])
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AC_MSG_RESULT([no])
fi
###########
# Filters #
###########
m4_define([SUPPORTED_FILTERS], [lzma1,lzma2,delta,x86,powerpc,ia64,arm,armthumb,arm64,sparc,riscv])dnl
m4_define([SIMPLE_FILTERS], [x86,powerpc,ia64,arm,armthumb,arm64,sparc,riscv])
m4_define([LZ_FILTERS], [lzma1,lzma2])
m4_foreach([NAME], [SUPPORTED_FILTERS],
[enable_filter_[]NAME=no
enable_encoder_[]NAME=no
enable_decoder_[]NAME=no
])dnl
AC_MSG_CHECKING([which encoders to build])
AC_ARG_ENABLE([encoders], AS_HELP_STRING([--enable-encoders=LIST],
[Comma-separated list of encoders to build. Default=all.
Available encoders:]
m4_translit(m4_defn([SUPPORTED_FILTERS]), [,], [ ])),
[], [enable_encoders=SUPPORTED_FILTERS])
enable_encoders=`echo "$enable_encoders" | sed 's/,/ /g'`
if test "x$enable_encoders" = xno || test "x$enable_encoders" = x; then
enable_encoders=no
AC_MSG_RESULT([(none)])
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else
for arg in $enable_encoders
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do
case $arg in m4_foreach([NAME], [SUPPORTED_FILTERS], [
NAME)
enable_filter_[]NAME=yes
enable_encoder_[]NAME=yes
AC_DEFINE(HAVE_ENCODER_[]m4_toupper(NAME), [1],
[Define to 1 if] NAME [encoder is enabled.])
;;])
*)
AC_MSG_RESULT([])
AC_MSG_ERROR([unknown filter: $arg])
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;;
esac
done
AC_DEFINE([HAVE_ENCODERS], [1],
[Define to 1 if any of HAVE_ENCODER_foo have been defined.])
AC_MSG_RESULT([$enable_encoders])
fi
AC_MSG_CHECKING([which decoders to build])
AC_ARG_ENABLE([decoders], AS_HELP_STRING([--enable-decoders=LIST],
[Comma-separated list of decoders to build. Default=all.
Available decoders are the same as available encoders.]),
[], [enable_decoders=SUPPORTED_FILTERS])
enable_decoders=`echo "$enable_decoders" | sed 's/,/ /g'`
if test "x$enable_decoders" = xno || test "x$enable_decoders" = x; then
enable_decoders=no
AC_MSG_RESULT([(none)])
else
for arg in $enable_decoders
do
case $arg in m4_foreach([NAME], [SUPPORTED_FILTERS], [
NAME)
enable_filter_[]NAME=yes
enable_decoder_[]NAME=yes
AC_DEFINE(HAVE_DECODER_[]m4_toupper(NAME), [1],
[Define to 1 if] NAME [decoder is enabled.])
;;])
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*)
AC_MSG_RESULT([])
AC_MSG_ERROR([unknown filter: $arg])
;;
esac
done
AC_DEFINE([HAVE_DECODERS], [1],
[Define to 1 if any of HAVE_DECODER_foo have been defined.])
AC_MSG_RESULT([$enable_decoders])
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fi
if test "x$enable_encoder_lzma2$enable_encoder_lzma1" = xyesno \
|| test "x$enable_decoder_lzma2$enable_decoder_lzma1" = xyesno; then
AC_MSG_ERROR([LZMA2 requires that LZMA1 is also enabled.])
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fi
AM_CONDITIONAL(COND_MAIN_ENCODER, test "x$enable_encoders" != xno)
AM_CONDITIONAL(COND_MAIN_DECODER, test "x$enable_decoders" != xno)
m4_foreach([NAME], [SUPPORTED_FILTERS],
[AM_CONDITIONAL(COND_FILTER_[]m4_toupper(NAME), test "x$enable_filter_[]NAME" = xyes)
AM_CONDITIONAL(COND_ENCODER_[]m4_toupper(NAME), test "x$enable_encoder_[]NAME" = xyes)
AM_CONDITIONAL(COND_DECODER_[]m4_toupper(NAME), test "x$enable_decoder_[]NAME" = xyes)
])dnl
# The so called "simple filters" share common code.
enable_filter_simple=no
enable_encoder_simple=no
enable_decoder_simple=no
m4_foreach([NAME], [SIMPLE_FILTERS],
[test "x$enable_filter_[]NAME" = xyes && enable_filter_simple=yes
test "x$enable_encoder_[]NAME" = xyes && enable_encoder_simple=yes
test "x$enable_decoder_[]NAME" = xyes && enable_decoder_simple=yes
])dnl
AM_CONDITIONAL(COND_FILTER_SIMPLE, test "x$enable_filter_simple" = xyes)
AM_CONDITIONAL(COND_ENCODER_SIMPLE, test "x$enable_encoder_simple" = xyes)
AM_CONDITIONAL(COND_DECODER_SIMPLE, test "x$enable_decoder_simple" = xyes)
# LZ-based filters share common code.
enable_filter_lz=no
enable_encoder_lz=no
enable_decoder_lz=no
m4_foreach([NAME], [LZ_FILTERS],
[test "x$enable_filter_[]NAME" = xyes && enable_filter_lz=yes
test "x$enable_encoder_[]NAME" = xyes && enable_encoder_lz=yes
test "x$enable_decoder_[]NAME" = xyes && enable_decoder_lz=yes
])dnl
AM_CONDITIONAL(COND_FILTER_LZ, test "x$enable_filter_lz" = xyes)
AM_CONDITIONAL(COND_ENCODER_LZ, test "x$enable_encoder_lz" = xyes)
AM_CONDITIONAL(COND_DECODER_LZ, test "x$enable_decoder_lz" = xyes)
#################
# Match finders #
#################
m4_define([SUPPORTED_MATCH_FINDERS], [hc3,hc4,bt2,bt3,bt4])
m4_foreach([NAME], [SUPPORTED_MATCH_FINDERS],
[enable_match_finder_[]NAME=no
])
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AC_MSG_CHECKING([which match finders to build])
AC_ARG_ENABLE([match-finders], AS_HELP_STRING([--enable-match-finders=LIST],
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[Comma-separated list of match finders to build. Default=all.
At least one match finder is required for encoding with
the LZMA1 and LZMA2 filters. Available match finders:]
m4_translit(m4_defn([SUPPORTED_MATCH_FINDERS]), [,], [ ])), [],
[enable_match_finders=SUPPORTED_MATCH_FINDERS])
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enable_match_finders=`echo "$enable_match_finders" | sed 's/,/ /g'`
if test "x$enable_encoder_lz" = xyes ; then
if test -z "$enable_match_finders"; then
AC_MSG_ERROR([At least one match finder is required for an LZ-based encoder.])
fi
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for arg in $enable_match_finders
do
case $arg in m4_foreach([NAME], [SUPPORTED_MATCH_FINDERS], [
NAME)
enable_match_finder_[]NAME=yes
AC_DEFINE(HAVE_MF_[]m4_toupper(NAME), [1],
[Define to 1 to enable] NAME [match finder.])
;;])
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*)
AC_MSG_RESULT([])
AC_MSG_ERROR([unknown match finder: $arg])
;;
esac
done
AC_MSG_RESULT([$enable_match_finders])
else
AC_MSG_RESULT([(none because not building any LZ-based encoder)])
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fi
####################
# Integrity checks #
####################
m4_define([SUPPORTED_CHECKS], [crc32,crc64,sha256])
m4_foreach([NAME], [SUPPORTED_CHECKS],
[enable_check_[]NAME=no
])dnl
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AC_MSG_CHECKING([which integrity checks to build])
AC_ARG_ENABLE([checks], AS_HELP_STRING([--enable-checks=LIST],
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[Comma-separated list of integrity checks to build.
Default=all. Available integrity checks:]
m4_translit(m4_defn([SUPPORTED_CHECKS]), [,], [ ])),
[], [enable_checks=SUPPORTED_CHECKS])
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enable_checks=`echo "$enable_checks" | sed 's/,/ /g'`
if test "x$enable_checks" = xno || test "x$enable_checks" = x; then
AC_MSG_RESULT([(none)])
else
for arg in $enable_checks
do
case $arg in m4_foreach([NAME], [SUPPORTED_CHECKS], [
NAME)
enable_check_[]NAME=yes
AC_DEFINE(HAVE_CHECK_[]m4_toupper(NAME), [1],
[Define to 1 if] NAME
[integrity check is enabled.])
;;])
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*)
AC_MSG_RESULT([])
AC_MSG_ERROR([unknown integrity check: $arg])
;;
esac
done
AC_MSG_RESULT([$enable_checks])
fi
if test "x$enable_check_crc32" = xno ; then
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AC_MSG_ERROR([For now, the CRC32 check must always be enabled.])
fi
m4_foreach([NAME], [SUPPORTED_CHECKS],
[AM_CONDITIONAL(COND_CHECK_[]m4_toupper(NAME), test "x$enable_check_[]NAME" = xyes)
])dnl
AC_MSG_CHECKING([if external SHA-256 should be used])
AC_ARG_ENABLE([external-sha256], AS_HELP_STRING([--enable-external-sha256],
[Use SHA-256 code from the operating system.
See INSTALL for possible subtle problems.]),
[], [enable_external_sha256=no])
if test "x$enable_check_sha256" != "xyes"; then
enable_external_sha256=no
fi
if test "x$enable_external_sha256" = xyes; then
AC_MSG_RESULT([yes])
else
AC_MSG_RESULT([no])
fi
#############
# MicroLZMA #
#############
AC_MSG_CHECKING([if MicroLZMA support should be built])
AC_ARG_ENABLE([microlzma], AS_HELP_STRING([--disable-microlzma],
[Do not build MicroLZMA encoder and decoder.
It is needed by specific applications only,
for example, erofs-utils.]),
[], [enable_microlzma=yes])
case $enable_microlzma in
yes | no)
AC_MSG_RESULT([$enable_microlzma])
;;
*)
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-microlzma accepts only 'yes' or 'no'.])
;;
esac
AM_CONDITIONAL(COND_MICROLZMA, test "x$enable_microlzma" = xyes)
#############################
# .lz (lzip) format support #
#############################
AC_MSG_CHECKING([if .lz (lzip) decompression support should be built])
AC_ARG_ENABLE([lzip-decoder], AS_HELP_STRING([--disable-lzip-decoder],
[Disable decompression support for .lz (lzip) files.]),
[], [enable_lzip_decoder=yes])
if test "x$enable_decoder_lzma1" != xyes; then
enable_lzip_decoder=no
AC_MSG_RESULT([no because LZMA1 decoder is disabled])
elif test "x$enable_lzip_decoder" = xyes; then
AC_DEFINE([HAVE_LZIP_DECODER], [1],
[Define to 1 if .lz (lzip) decompression support is enabled.])
AC_MSG_RESULT([yes])
else
AC_MSG_RESULT([no])
fi
AM_CONDITIONAL(COND_LZIP_DECODER, test "x$enable_lzip_decoder" = xyes)
###########################
# Assembler optimizations #
###########################
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AC_MSG_CHECKING([if assembler optimizations should be used])
AC_ARG_ENABLE([assembler], AS_HELP_STRING([--disable-assembler],
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[Do not use assembler optimizations even if such exist
for the architecture.]),
[], [enable_assembler=yes])
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if test "x$enable_assembler" = xyes; then
enable_assembler=no
case $host_os in
# Darwin should work too but only if not creating universal
# binaries. Solaris x86 could work too but I cannot test.
linux* | *bsd* | mingw* | cygwin | msys | *djgpp*)
case $host_cpu in
i?86) enable_assembler=x86 ;;
esac
;;
esac
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fi
case $enable_assembler in
x86 | no)
AC_MSG_RESULT([$enable_assembler])
;;
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*)
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-assembler accepts only 'yes', 'no', or 'x86' (32-bit).])
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;;
esac
AM_CONDITIONAL(COND_ASM_X86, test "x$enable_assembler" = xx86)
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
#############
# CLMUL CRC #
#############
AC_ARG_ENABLE([clmul-crc], AS_HELP_STRING([--disable-clmul-crc],
[Do not use carryless multiplication for CRC calculation
even if support for it is detected.]),
[], [enable_clmul_crc=yes])
############################
# ARM64 CRC32 Instructions #
############################
AC_ARG_ENABLE([arm64-crc32], AS_HELP_STRING([--disable-arm64-crc32],
[Do not use ARM64 CRC32 instructions even if support for it
is detected.]),
[], [enable_arm64_crc32=yes])
#####################
# Size optimization #
#####################
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AC_MSG_CHECKING([if small size is preferred over speed])
AC_ARG_ENABLE([small], AS_HELP_STRING([--enable-small],
[Make liblzma smaller and a little slower.
This is disabled by default to optimize for speed.]),
[], [enable_small=no])
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if test "x$enable_small" = xyes; then
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AC_DEFINE([HAVE_SMALL], [1], [Define to 1 if optimizing for size.])
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elif test "x$enable_small" != xno; then
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-small accepts only 'yes' or 'no'])
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fi
AC_MSG_RESULT([$enable_small])
AM_CONDITIONAL(COND_SMALL, test "x$enable_small" = xyes)
#############
# Threading #
#############
AC_MSG_CHECKING([if threading support is wanted])
AC_ARG_ENABLE([threads], AS_HELP_STRING([--enable-threads=METHOD],
[Supported METHODS are 'yes', 'no', 'posix', 'win95', and
'vista'. The default is 'yes'. Using 'no' together with
--enable-small makes liblzma thread unsafe.]),
[], [enable_threads=yes])
if test "x$enable_threads" = xyes; then
case $host_os in
mingw*)
case $host_cpu in
i?86) enable_threads=win95 ;;
*) enable_threads=vista ;;
esac
;;
*)
enable_threads=posix
;;
esac
fi
case $enable_threads in
posix | win95 | vista)
AC_MSG_RESULT([yes, $enable_threads])
;;
no)
AC_MSG_RESULT([no])
;;
*)
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-threads only accepts 'yes', 'no', 'posix', 'win95', or 'vista'])
;;
esac
# We use the actual result a little later.
#########################
# Assumed amount of RAM #
#########################
# We use 128 MiB as default, because it will allow decompressing files
# created with "xz -9". It would be slightly safer to guess a lower value,
# but most systems, on which we don't have any way to determine the amount
# of RAM, will probably have at least 128 MiB of RAM.
AC_MSG_CHECKING([how much RAM to assume if the real amount is unknown])
AC_ARG_ENABLE([assume-ram], AS_HELP_STRING([--enable-assume-ram=SIZE],
[If and only if the real amount of RAM cannot be determined,
assume SIZE MiB. The default is 128 MiB. This affects the
default memory usage limit.]),
[], [enable_assume_ram=128])
assume_ram_check=`echo "$enable_assume_ram" | tr -d 0123456789`
if test -z "$enable_assume_ram" || test -n "$assume_ram_check"; then
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-assume-ram accepts only an integer argument])
fi
AC_MSG_RESULT([$enable_assume_ram MiB])
AC_DEFINE_UNQUOTED([ASSUME_RAM], [$enable_assume_ram],
[How many MiB of RAM to assume if the real amount cannot
be determined.])
#########################
# Components to install #
#########################
AC_ARG_ENABLE([xz], [AS_HELP_STRING([--disable-xz],
[do not build the xz tool])],
[], [enable_xz=yes])
AM_CONDITIONAL([COND_XZ], [test x$enable_xz != xno])
AC_ARG_ENABLE([xzdec], [AS_HELP_STRING([--disable-xzdec],
[do not build xzdec])],
[], [enable_xzdec=yes])
test "x$enable_decoders" = xno && enable_xzdec=no
AM_CONDITIONAL([COND_XZDEC], [test x$enable_xzdec != xno])
AC_ARG_ENABLE([lzmadec], [AS_HELP_STRING([--disable-lzmadec],
[do not build lzmadec
(it exists primarily for LZMA Utils compatibility)])],
[], [enable_lzmadec=yes])
test "x$enable_decoder_lzma1" = xno && enable_lzmadec=no
AM_CONDITIONAL([COND_LZMADEC], [test x$enable_lzmadec != xno])
AC_ARG_ENABLE([lzmainfo], [AS_HELP_STRING([--disable-lzmainfo],
[do not build lzmainfo
(it exists primarily for LZMA Utils compatibility)])],
[], [enable_lzmainfo=yes])
test "x$enable_decoder_lzma1" = xno && enable_lzmainfo=no
AM_CONDITIONAL([COND_LZMAINFO], [test x$enable_lzmainfo != xno])
AC_ARG_ENABLE([lzma-links], [AS_HELP_STRING([--disable-lzma-links],
[do not create symlinks for LZMA Utils compatibility])],
[], [enable_lzma_links=yes])
AM_CONDITIONAL([COND_LZMALINKS], [test x$enable_lzma_links != xno])
AC_ARG_ENABLE([scripts], [AS_HELP_STRING([--disable-scripts],
[do not install the scripts xzdiff, xzgrep, xzless, xzmore,
and their symlinks])],
[], [enable_scripts=yes])
AM_CONDITIONAL([COND_SCRIPTS], [test x$enable_scripts != xno])
AC_ARG_ENABLE([doc], [AS_HELP_STRING([--disable-doc],
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[do not install documentation files to docdir
(man pages are still installed and,
if --enable-doxygen is used,
liblzma API documentation is installed too)])],
2014-04-25 14:44:26 +00:00
[], [enable_doc=yes])
AM_CONDITIONAL([COND_DOC], [test x$enable_doc != xno])
AC_ARG_ENABLE([doxygen], [AS_HELP_STRING([--enable-doxygen],
[generate HTML version of the liblzma API documentation
using Doxygen and install the result to docdir])],
[], [enable_doxygen=no])
AM_CONDITIONAL([COND_DOXYGEN], [test x$enable_doxygen != xno])
##############
# Sandboxing #
##############
AC_MSG_CHECKING([if sandboxing should be used])
AC_ARG_ENABLE([sandbox], [AS_HELP_STRING([--enable-sandbox=METHOD],
[Sandboxing METHOD can be
'auto', 'no', 'capsicum', 'pledge', or 'landlock'.
The default is 'auto' which enables sandboxing if
a supported sandboxing method is found.])],
[], [enable_sandbox=auto])
case $enable_xzdec-$enable_xz-$enable_sandbox in
no-no-*)
enable_sandbox=no
AC_MSG_RESULT([no, --disable-xz and --disable-xzdec was used])
;;
*-*-auto)
AC_MSG_RESULT([maybe (autodetect)])
;;
*-*-no | *-*-capsicum | *-*-pledge | *-*-landlock)
AC_MSG_RESULT([$enable_sandbox])
;;
*)
AC_MSG_RESULT([])
AC_MSG_ERROR([--enable-sandbox only accepts 'auto', 'no', 'capsicum', 'pledge', or 'landlock'.])
;;
esac
###########################
# PATH prefix for scripts #
###########################
# The scripts can add a prefix to the search PATH so that POSIX tools
# or the xz binary is always in the PATH.
AC_ARG_ENABLE([path-for-scripts],
[AS_HELP_STRING([--enable-path-for-scripts=PREFIX],
[If PREFIX isn't empty, PATH=PREFIX:$PATH will be set in
the beginning of the scripts (xzgrep and others).
The default is empty except on Solaris the default is
/usr/xpg4/bin.])],
[], [
case $host_os in
solaris*) enable_path_for_scripts=/usr/xpg4/bin ;;
*) enable_path_for_scripts= ;;
esac
])
if test -n "$enable_path_for_scripts" && test "x$enable_path_for_scripts" != xno ; then
enable_path_for_scripts="PATH=$enable_path_for_scripts:\$PATH"
else
enable_path_for_scripts=
fi
AC_SUBST([enable_path_for_scripts])
2008-01-06 19:47:17 +00:00
###############################################################################
# Checks for programs.
###############################################################################
echo
case $host_os in
solaris*)
# The gnulib POSIX shell macro below may pick a shell that
# doesn't work with xzgrep. Workaround by picking a shell
# that is known to work.
if test -z "$gl_cv_posix_shell" && test -x /usr/xpg4/bin/sh; then
gl_cv_posix_shell=/usr/xpg4/bin/sh
fi
;;
esac
gl_POSIX_SHELL
if test -z "$POSIX_SHELL" && test "x$enable_scripts" = xyes ; then
AC_MSG_ERROR([No POSIX conforming shell (sh) was found.])
fi
2007-12-08 22:42:33 +00:00
echo
echo "Initializing Automake:"
# We don't use "subdir-objects" yet because it breaks "make distclean" when
# dependencies are enabled (as of Automake 1.14.1) due to this bug:
# https://debbugs.gnu.org/cgi/bugreport.cgi?bug=17354
# The -Wno-unsupported is used to silence warnings about missing
# "subdir-objects".
AM_INIT_AUTOMAKE([1.12 foreign tar-v7 filename-length-max=99 -Wno-unsupported])
2008-01-06 19:47:17 +00:00
AC_PROG_LN_S
dnl # Autoconf >= 2.70 warns that AC_PROG_CC_C99 is obsolete. However,
dnl # we have to keep using AC_PROG_CC_C99 instead of AC_PROG_CC
dnl # as long as we try to be compatible with Autoconf 2.69.
AC_PROG_CC_C99
if test x$ac_cv_prog_cc_c99 = xno ; then
AC_MSG_ERROR([No C99 compiler was found.])
fi
2007-12-08 22:42:33 +00:00
AM_PROG_CC_C_O
AM_PROG_AS
2008-01-06 19:47:17 +00:00
AC_USE_SYSTEM_EXTENSIONS
2007-12-08 22:42:33 +00:00
AS_CASE([$enable_threads],
[posix], [
echo
echo "POSIX threading support:"
AX_PTHREAD([:]) dnl We don't need the HAVE_PTHREAD macro.
LIBS="$LIBS $PTHREAD_LIBS"
AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS"
dnl NOTE: PTHREAD_CC is ignored. It would be useful on AIX,
dnl but it's tricky to get it right together with
dnl AC_PROG_CC_C99. Thus, this is handled by telling the
dnl user in INSTALL to set the correct CC manually.
AC_DEFINE([MYTHREAD_POSIX], [1],
[Define to 1 when using POSIX threads (pthreads).])
# This is nice to have but not mandatory.
OLD_CFLAGS=$CFLAGS
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
AC_CHECK_FUNCS([pthread_condattr_setclock])
CFLAGS=$OLD_CFLAGS
],
[win95], [
AC_DEFINE([MYTHREAD_WIN95], [1], [Define to 1 when using
Windows 95 (and thus XP) compatible threads.
This avoids use of features that were added in
Windows Vista.])
],
[vista], [
AC_DEFINE([MYTHREAD_VISTA], [1], [Define to 1 when using
Windows Vista compatible threads. This uses
features that are not available on Windows XP.])
]
)
AM_CONDITIONAL([COND_THREADS], [test "x$enable_threads" != xno])
2007-12-08 22:42:33 +00:00
echo
echo "Initializing Libtool:"
LT_PREREQ([2.4])
2009-08-27 12:43:54 +00:00
LT_INIT([win32-dll])
LT_LANG([Windows Resource])
2007-12-08 22:42:33 +00:00
# This is a bit wrong since it is possible to request that only some libs
# are built as shared. Using that feature isn't so common though, and this
# breaks only on Windows (at least for now) if the user enables only some
# libs as shared.
AM_CONDITIONAL([COND_SHARED], [test "x$enable_shared" != xno])
#####################
# Symbol versioning #
#####################
# NOTE: This checks if we are building shared or static library
# and if --with-pic or --without-pic was used. Thus this check
# must be after Libtool initialization.
AC_MSG_CHECKING([if library symbol versioning should be used])
AC_ARG_ENABLE([symbol-versions], [AS_HELP_STRING([--enable-symbol-versions],
[Use symbol versioning for liblzma. Enabled by default on
GNU/Linux, other GNU-based systems, and FreeBSD.])],
[], [enable_symbol_versions=auto])
if test "x$enable_symbol_versions" = xauto; then
case $host_os in
# NOTE: Even if one omits -gnu on GNU/Linux (e.g.
# i486-slackware-linux), configure will (via config.sub)
# append -gnu (e.g. i486-slackware-linux-gnu), and this
# test will work correctly.
gnu* | *-gnu* | freebsd*)
enable_symbol_versions=yes
;;
*)
enable_symbol_versions=no
;;
esac
fi
# There are two variants for symbol versioning.
# See src/liblzma/validate_map.sh for details.
#
# On GNU/Linux, extra symbols are added in the C code. These extra symbols
# must not be put into a static library as they can cause problems (and
# even if they didn't cause problems, they would be useless). On other
# systems symbol versioning may be used too but there is no problem as only
# a linker script is specified in src/liblzma/Makefile.am and that isn't
# used when creating a static library.
#
# Libtool always uses -DPIC when building shared libraries by default and
2023-07-31 12:02:21 +00:00
# doesn't use it for static libs by default. This can be overridden with
# --with-pic and --without-pic though. As long as neither --with-pic nor
# --without-pic is used then we can use #ifdef PIC to detect if the file is
# being built for a shared library.
AS_IF([test "x$enable_symbol_versions" = xno], [
enable_symbol_versions=no
AC_MSG_RESULT([no])
], [test "x$enable_shared" = xno], [
enable_symbol_versions=no
AC_MSG_RESULT([no (not building a shared library)])
], [
# "yes" means that symbol version are to be used but we need to
# autodetect which variant to use.
if test "x$enable_symbol_versions" = xyes ; then
case "$host_cpu-$host_os" in
microblaze*)
# GCC 12 on MicroBlaze doesn't support
# __symver__ attribute. It's simplest and
# safest to use the generic version on that
# platform since then only the linker script
# is needed. The RHEL/CentOS 7 compatibility
# symbols don't matter on MicroBlaze.
enable_symbol_versions=generic
;;
*-linux*)
# NVIDIA HPC Compiler doesn't support symbol
# versioning but the linker script can still
# be used.
AC_EGREP_CPP([use_generic_symbol_versioning],
[#ifdef __NVCOMPILER
use_generic_symbol_versioning
#endif],
[enable_symbol_versions=generic],
[enable_symbol_versions=linux])
;;
*)
enable_symbol_versions=generic
;;
esac
fi
if test "x$enable_symbol_versions" = xlinux ; then
case "$pic_mode-$enable_static" in
default-*)
# Use symvers if PIC is defined.
have_symbol_versions_linux=2
;;
*-no)
# Not building static library.
# Use symvers unconditionally.
have_symbol_versions_linux=1
;;
*)
AC_MSG_RESULT([])
AC_MSG_ERROR([
On GNU/Linux, building both shared and static library at the same time
is not supported if --with-pic or --without-pic is used.
Use either --disable-shared or --disable-static to build one type
of library at a time. If both types are needed, build one at a time,
possibly picking only src/liblzma/.libs/liblzma.a from the static build.])
;;
esac
AC_DEFINE_UNQUOTED([HAVE_SYMBOL_VERSIONS_LINUX],
[$have_symbol_versions_linux],
[Define to 1 to if GNU/Linux-specific details
are unconditionally wanted for symbol
versioning. Define to 2 to if these are wanted
only if also PIC is defined (allows building
both shared and static liblzma at the same
time with Libtool if neither --with-pic nor
--without-pic is used). This define must be
used together with liblzma_linux.map.])
elif test "x$enable_symbol_versions" != xgeneric ; then
AC_MSG_RESULT([])
AC_MSG_ERROR([unknown symbol versioning variant '$enable_symbol_versions'])
fi
AC_MSG_RESULT([yes ($enable_symbol_versions)])
])
AM_CONDITIONAL([COND_SYMVERS_LINUX],
[test "x$enable_symbol_versions" = xlinux])
AM_CONDITIONAL([COND_SYMVERS_GENERIC],
[test "x$enable_symbol_versions" = xgeneric])
2007-12-08 22:42:33 +00:00
###############################################################################
# Checks for libraries.
###############################################################################
dnl Support for _REQUIRE_VERSION was added in gettext 0.19.6. If both
dnl _REQUIRE_VERSION and _VERSION are present, the _VERSION is ignored.
dnl We use both for compatibility with other programs in the Autotools family.
2007-12-08 22:42:33 +00:00
echo
echo "Initializing gettext:"
AM_GNU_GETTEXT_REQUIRE_VERSION([0.19.6])
AM_GNU_GETTEXT_VERSION([0.19.6])
2007-12-08 22:42:33 +00:00
AM_GNU_GETTEXT([external])
2007-12-08 22:42:33 +00:00
###############################################################################
# Checks for header files.
###############################################################################
echo
echo "System headers and functions:"
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
# immintrin.h allows the use of the intrinsic functions if they are available.
# cpuid.h may be used for detecting x86 processor features at runtime.
AC_CHECK_HEADERS([immintrin.h cpuid.h])
2007-12-08 22:42:33 +00:00
###############################################################################
# Checks for typedefs, structures, and compiler characteristics.
###############################################################################
AC_HEADER_STDBOOL
AC_TYPE_UINT8_T
2008-11-19 21:55:22 +00:00
AC_TYPE_UINT16_T
AC_TYPE_INT32_T
AC_TYPE_UINT32_T
AC_TYPE_INT64_T
AC_TYPE_UINT64_T
AC_TYPE_UINTPTR_T
AC_CHECK_SIZEOF([size_t])
2007-12-08 22:42:33 +00:00
# The command line tool can copy high resolution timestamps if such
# information is available in struct stat. Otherwise one second accuracy
# is used.
AC_CHECK_MEMBERS([
struct stat.st_atim.tv_nsec,
struct stat.st_atimespec.tv_nsec,
struct stat.st_atimensec,
struct stat.st_uatime,
struct stat.st_atim.st__tim.tv_nsec])
2007-12-08 22:42:33 +00:00
AC_SYS_LARGEFILE
AC_C_BIGENDIAN
# __attribute__((__constructor__)) can be used for one-time initializations.
# Use -Werror because some compilers accept unknown attributes and just
# give a warning.
#
# FIXME? Unfortunately -Werror can cause trouble if CFLAGS contains options
# that produce warnings for unrelated reasons. For example, GCC and Clang
# support -Wunused-macros which will warn about "#define _GNU_SOURCE 1"
# which will be among the #defines that Autoconf inserts to the beginning of
# the test program. There seems to be no nice way to prevent Autoconf from
# inserting the any defines to the test program.
AC_MSG_CHECKING([if __attribute__((__constructor__)) can be used])
have_func_attribute_constructor=no
OLD_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -Werror"
Build: Silence two Autoconf warnings. There were two uses of AC_COMPILE_IFELSE that didn't use AC_LANG_SOURCE and Autoconf warned about these. The omission had been intentional but it turned out that this didn't do what I thought it would. Autoconf 2.71 manual gives an impression that AC_LANG_SOURCE inserts all #defines that have been made with AC_DEFINE so far (confdefs.h). The idea was that omitting AC_LANG_SOURCE would mean that only the exact code included in the AC_COMPILE_IFELSE call would be compiled. With C programs this is not true: the #defines get added without AC_LANG_SOURCE too. There seems to be no neat way to avoid this. Thus, with the C language at least, adding AC_LANG_SOURCE makes no other difference than silencing a warning from Autoconf. The generated "configure" remains identical. (Docs of AC_LANG_CONFTEST say that the #defines have been inserted since Autoconf 2.63b and that AC_COMPILE_IFELSE uses AC_LANG_CONFTEST. So the behavior is documented if one also reads the docs of macros that one isn't calling directly.) Any extra code, including #defines, can cause problems for these two tests because these tests must use -Werror. CC=clang CFLAGS=-Weverything is the most extreme example. It enables -Wreserved-macro-identifier which warns about #define __EXTENSIONS__ 1 because it begins with two underscores. It's possible to write a test file that passes -Weverything but it becomes impossible when Autoconf inserts confdefs.h. So this commit adds AC_LANG_SOURCE to silence Autoconf warnings. A different solution is needed for -Werror tests.
2023-09-26 10:14:37 +00:00
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
__attribute__((__constructor__))
static void my_constructor_func(void) { return; }
Build: Silence two Autoconf warnings. There were two uses of AC_COMPILE_IFELSE that didn't use AC_LANG_SOURCE and Autoconf warned about these. The omission had been intentional but it turned out that this didn't do what I thought it would. Autoconf 2.71 manual gives an impression that AC_LANG_SOURCE inserts all #defines that have been made with AC_DEFINE so far (confdefs.h). The idea was that omitting AC_LANG_SOURCE would mean that only the exact code included in the AC_COMPILE_IFELSE call would be compiled. With C programs this is not true: the #defines get added without AC_LANG_SOURCE too. There seems to be no neat way to avoid this. Thus, with the C language at least, adding AC_LANG_SOURCE makes no other difference than silencing a warning from Autoconf. The generated "configure" remains identical. (Docs of AC_LANG_CONFTEST say that the #defines have been inserted since Autoconf 2.63b and that AC_COMPILE_IFELSE uses AC_LANG_CONFTEST. So the behavior is documented if one also reads the docs of macros that one isn't calling directly.) Any extra code, including #defines, can cause problems for these two tests because these tests must use -Werror. CC=clang CFLAGS=-Weverything is the most extreme example. It enables -Wreserved-macro-identifier which warns about #define __EXTENSIONS__ 1 because it begins with two underscores. It's possible to write a test file that passes -Weverything but it becomes impossible when Autoconf inserts confdefs.h. So this commit adds AC_LANG_SOURCE to silence Autoconf warnings. A different solution is needed for -Werror tests.
2023-09-26 10:14:37 +00:00
]])], [
AC_DEFINE([HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR], [1],
[Define to 1 if __attribute__((__constructor__))
is supported for functions.])
have_func_attribute_constructor=yes
AC_MSG_RESULT([yes])
], [
AC_MSG_RESULT([no])
])
CFLAGS="$OLD_CFLAGS"
# The Win95 threading lacks a thread-safe one-time initialization function.
# The one-time initialization is needed for crc32_small.c and crc64_small.c
# create the CRC tables. So if small mode is enabled, the threading mode is
# win95, and the compiler does not support attribute constructor, then we
# would end up with a multithreaded build that is thread-unsafe. As a
# result this configuration is not allowed.
if test "x$enable_small$enable_threads$have_func_attribute_constructor" \
= xyeswin95no; then
AC_MSG_ERROR([
--enable-threads=win95 and --enable-small cannot be used
at the same time with a compiler that doesn't support
__attribute__((__constructor__))])
fi
2007-12-08 22:42:33 +00:00
###############################################################################
# Checks for library functions.
###############################################################################
# Gnulib replacements as needed
gl_GETOPT
# If clock_gettime() is available, liblzma with pthreads may use it, and
# xz may use it even when threading support is disabled. In XZ Utils 5.4.x
# and older, configure checked for clock_gettime() only when using pthreads.
# This way non-threaded builds of liblzma didn't get a useless dependency on
# librt which further had a dependency on libpthread. Avoiding these was
# useful when a small build was needed, for example, for initramfs use.
#
# The above reasoning is thoroughly obsolete: On GNU/Linux, librt hasn't
# been needed for clock_gettime() since glibc 2.17 (2012-12-25).
# Solaris 10 needs librt but Solaris 11 doesn't anymore.
AC_SEARCH_LIBS([clock_gettime], [rt])
AC_CHECK_FUNCS([clock_gettime])
AC_CHECK_DECL([CLOCK_MONOTONIC], [AC_DEFINE([HAVE_CLOCK_MONOTONIC], [1],
[Define to 1 if 'CLOCK_MONOTONIC' is declared in <time.h>.])], [],
[[#include <time.h>]])
# Find the best function to set timestamps.
AC_CHECK_FUNCS([futimens futimes futimesat utimes _futime utime], [break])
2007-12-08 22:42:33 +00:00
# This is nice to have but not mandatory.
AC_CHECK_FUNCS([posix_fadvise])
TUKLIB_PROGNAME
TUKLIB_INTEGER
TUKLIB_PHYSMEM
TUKLIB_CPUCORES
TUKLIB_MBSTR
2007-12-08 22:42:33 +00:00
2019-06-24 21:16:06 +00:00
# If requested, check for system-provided SHA-256. At least the following
# implementations are supported:
#
# OS Headers Library Type Function
# FreeBSD sys/types.h + sha256.h libmd SHA256_CTX SHA256_Init
# NetBSD sys/types.h + sha2.h SHA256_CTX SHA256_Init
# OpenBSD sys/types.h + sha2.h SHA2_CTX SHA256Init
# Solaris sys/types.h + sha2.h libmd SHA256_CTX SHA256Init
# MINIX 3 sys/types.h + sha2.h SHA256_CTX SHA256_Init
# Darwin CommonCrypto/CommonDigest.h CC_SHA256_CTX CC_SHA256_Init
#
# Note that Darwin's CC_SHA256_Update takes buffer size as uint32_t instead
# of size_t.
#
sha256_header_found=no
sha256_type_found=no
sha256_func_found=no
AS_IF([test "x$enable_external_sha256" = "xyes"], [
# Test for Common Crypto before others, because Darwin has sha256.h
# too and we don't want to use that, because on older versions it
# uses OpenSSL functions, whose SHA256_Init is not guaranteed to
# succeed.
AC_CHECK_HEADERS(
[CommonCrypto/CommonDigest.h sha256.h sha2.h],
[sha256_header_found=yes ; break])
if test "x$sha256_header_found" = xyes; then
AC_CHECK_TYPES([CC_SHA256_CTX, SHA256_CTX, SHA2_CTX],
[sha256_type_found=yes], [],
[[#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#ifdef HAVE_COMMONCRYPTO_COMMONDIGEST_H
# include <CommonCrypto/CommonDigest.h>
#endif
#ifdef HAVE_SHA256_H
# include <sha256.h>
#endif
#ifdef HAVE_SHA2_H
# include <sha2.h>
#endif]])
if test "x$sha256_type_found" = xyes ; then
AC_SEARCH_LIBS([SHA256Init], [md])
AC_SEARCH_LIBS([SHA256_Init], [md])
AC_CHECK_FUNCS([CC_SHA256_Init SHA256Init SHA256_Init],
[sha256_func_found=yes ; break])
fi
fi
])
AM_CONDITIONAL([COND_INTERNAL_SHA256], [test "x$sha256_func_found" = xno])
if test "x$enable_external_sha256$sha256_func_found" = xyesno; then
AC_MSG_ERROR([--enable-external-sha256 was specified but no supported external SHA-256 implementation was found])
fi
# Check for SSE2 intrinsics. There is no run-time detection for SSE2 so if
# compiler options enable SSE2 then SSE2 support is required by the binaries.
# The compile-time check for SSE2 is done with #ifdefs because some compilers
# (ICC, MSVC) allow SSE2 intrinsics even when SSE2 isn't enabled.
AC_CHECK_DECL([_mm_movemask_epi8],
[AC_DEFINE([HAVE__MM_MOVEMASK_EPI8], [1],
[Define to 1 if _mm_movemask_epi8 is available.])],
[],
[#ifdef HAVE_IMMINTRIN_H
#include <immintrin.h>
#endif])
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
# For faster CRC on 32/64-bit x86 and E2K (see also crc64_fast.c):
#
# - Check for the CLMUL intrinsic _mm_clmulepi64_si128 in <immintrin.h>.
# Check also for _mm_set_epi64x for consistency with CMake build
# where it's needed to disable CLMUL with VS2013.
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
#
# - Check that __attribute__((__target__("ssse3,sse4.1,pclmul"))) works
# together with _mm_clmulepi64_si128 from <immintrin.h>. The attribute
# was added in GCC 4.4 but some GCC 4.x versions don't allow intrinsics
# with it. Exception: it must be not be used with EDG-based compilers
# like ICC and the compiler on E2K.
#
# If everything above is supported, runtime detection will be used to keep the
# binaries working on systems that don't support the required extensions.
AC_MSG_CHECKING([if _mm_clmulepi64_si128 is usable])
AS_IF([test "x$enable_clmul_crc" = xno], [
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
AC_MSG_RESULT([no, --disable-clmul-crc was used])
], [
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <immintrin.h>
// CLMUL works on older E2K instruction set but it is slow due to emulation.
#if defined(__e2k__) && __iset__ < 6
# error
#endif
// Intel's old compiler (ICC) can define __GNUC__ but the attribute must not
// be used with it. The new Clang-based ICX needs the attribute.
// Checking for !defined(__EDG__) catches ICC and other EDG-based compilers.
#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
__attribute__((__target__("ssse3,sse4.1,pclmul")))
#endif
int main(void)
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
{
__m128i a = _mm_set_epi64x(1, 2);
a = _mm_clmulepi64_si128(a, a, 0);
return 0;
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
}
]])], [
AC_DEFINE([HAVE_USABLE_CLMUL], [1],
[Define to 1 if _mm_set_epi64x and
_mm_clmulepi64_si128 are usable.
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
See configure.ac for details.])
enable_clmul_crc=yes
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
], [
enable_clmul_crc=no
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
])
AC_MSG_RESULT([$enable_clmul_crc])
])
liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL. It also works on E2K as it supports these intrinsics. On x86-64 runtime detection is used so the code keeps working on older processors too. A CLMUL-only build can be done by using -msse4.1 -mpclmul in CFLAGS and this will reduce the library size since the generic implementation and its 8 KiB lookup table will be omitted. On 32-bit x86 this isn't used by default for now because by default on 32-bit x86 the separate assembly file crc64_x86.S is used. If --disable-assembler is used then this new CLMUL code is used the same way as on 64-bit x86. However, a CLMUL-only build (-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on 32-bit x86 due to a currently-missing check for disabled assembler usage. The configure.ac check should be such that the code won't be built if something in the toolchain doesn't support it but --disable-clmul-crc option can be used to unconditionally disable this feature. CLMUL speeds up decompression of files that have compressed very well (assuming CRC64 is used as a check type). It is know that the CLMUL code is significantly slower than the generic code for tiny inputs (especially 1-8 bytes but up to 16 bytes). If that is a real-world problem then there is already a commented-out variant that uses the generic version for small inputs. Thanks to Ilya Kurdyukov for the original patch which was derived from a white paper from Intel [1] (published in 2009) and public domain code from [2] (released in 2016). [1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf [2] https://github.com/rawrunprotected/crc
2022-11-14 19:34:57 +00:00
# ARM64 C Language Extensions define CRC32 functions in arm_acle.h.
# These are supported by at least GCC and Clang which both need
# __attribute__((__target__("+crc"))), unless the needed compiler flags
# are used to support the CRC instruction.
AC_MSG_CHECKING([if ARM64 CRC32 instruction is usable])
AS_IF([test "x$enable_arm64_crc32" = xno], [
AC_MSG_RESULT([no, --disable-arm64-crc32 was used])
], [
AC_LINK_IFELSE([AC_LANG_SOURCE([[
#include <arm_acle.h>
#include <stdint.h>
#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
__attribute__((__target__("+crc")))
#endif
int main(void)
{
return __crc32d(1, 2) != 0;
}
]])], [
AC_DEFINE([HAVE_ARM64_CRC32], [1],
[Define to 1 if ARM64 CRC32 instruction is supported.
See configure.ac for details.])
enable_arm64_crc32=yes
], [
enable_arm64_crc32=no
])
AC_MSG_RESULT([$enable_arm64_crc32])
])
# Check for ARM64 CRC32 instruction runtime detection.
# getauxval() is supported on Linux, elf_aux_info() on FreeBSD, and
# sysctlbyname("hw.optional.armv8_crc32", ...) is supported on Darwin
# (macOS, iOS, etc.). Note that sysctlbyname() is supported on FreeBSD,
# NetBSD, and possibly others too but the string is specific to Apple OSes.
# The C code is responsible for checking defined(__APPLE__) before using
# sysctlbyname("hw.optional.armv8_crc32", ...).
AS_IF([test "x$enable_arm64_crc32" = xyes], [
AC_CHECK_FUNCS([getauxval elf_aux_info sysctlbyname], [break])
])
# Check for sandbox support. If one is found, set enable_sandbox=found.
#
# About -fsanitize: Of our three sandbox methods, only Landlock is
# incompatible with -fsanitize. FreeBSD 13.2 with Capsicum was tested with
# -fsanitize=address,undefined and had no issues. OpenBSD (as of version
# 7.4) has minimal support for process instrumentation. OpenBSD does not
# distribute the additional libraries needed (libasan, libubsan, etc.) with
# GCC or Clang needed for runtime sanitization support and instead only
# support -fsanitize-minimal-runtime for minimal undefined behavior
# sanitization. This minimal support is compatible with our use of the
# Pledge sandbox. So only Landlock will result in a build that cannot
# compress or decompress a single file to standard out.
AS_CASE([$enable_sandbox],
[auto | capsicum], [
AC_CHECK_FUNCS([cap_rights_limit], [enable_sandbox=found])
]
)
AS_CASE([$enable_sandbox],
[auto | pledge], [
AC_CHECK_FUNCS([pledge], [enable_sandbox=found])
]
)
AS_CASE([$enable_sandbox],
[auto | landlock], [
AC_MSG_CHECKING([if Linux Landlock is usable])
# A compile check is done here because some systems have
# linux/landlock.h, but do not have the syscalls defined
# in order to actually use Linux Landlock.
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <linux/landlock.h>
#include <sys/syscall.h>
#include <sys/prctl.h>
int main(void)
{
(void)prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
(void)SYS_landlock_create_ruleset;
(void)SYS_landlock_restrict_self;
(void)LANDLOCK_CREATE_RULESET_VERSION;
return 0;
}
]])], [
enable_sandbox=found
AS_CASE([$CFLAGS], [*-fsanitize=*], [AC_MSG_ERROR([
CFLAGS contains '-fsanitize=' which is incompatible with the Landlock
sandboxing. Use --disable-sandbox when using '-fsanitize'.])])
AC_DEFINE([HAVE_LINUX_LANDLOCK], [1],
[Define to 1 if Linux Landlock is supported.
See configure.ac for details.])
AC_MSG_RESULT([yes])
], [
AC_MSG_RESULT([no])
])
]
)
# If a specific sandboxing method was explicitly requested and it wasn't
# found, give an error.
case $enable_sandbox in
auto | no | found)
;;
*)
AC_MSG_ERROR([$enable_sandbox support not found])
;;
esac
2007-12-08 22:42:33 +00:00
###############################################################################
# If using GCC, set some additional AM_CFLAGS:
2007-12-08 22:42:33 +00:00
###############################################################################
if test "$GCC" = yes ; then
2007-12-08 22:42:33 +00:00
echo
echo "GCC extensions:"
fi
# Always do the visibility check but don't set AM_CFLAGS on Windows.
# This way things get set properly even on Windows.
gl_VISIBILITY
if test -n "$CFLAG_VISIBILITY" && test "$is_w32" = no; then
AM_CFLAGS="$AM_CFLAGS $CFLAG_VISIBILITY"
fi
2007-12-08 22:42:33 +00:00
AS_IF([test "$GCC" = yes], [
2007-12-08 22:42:33 +00:00
# Enable as much warnings as possible. These commented warnings won't
2008-12-12 22:54:11 +00:00
# work for this package though:
2007-12-08 22:42:33 +00:00
# * -Wunreachable-code breaks several assert(0) cases, which are
# backed up with "return LZMA_PROG_ERROR".
# * -Wcast-qual would break various things where we need a non-const
# pointer although we don't modify anything through it.
# * -Winline, -Wdisabled-optimization, -Wunsafe-loop-optimizations
# don't seem so useful here; at least the last one gives some
# warnings which are not bugs.
# * -Wconversion still shows too many warnings.
#
# The flags before the empty line are for GCC and many of them
# are supported by Clang too. The flags after the empty line are
# for Clang.
for NEW_FLAG in \
-Wall \
-Wextra \
-Wvla \
-Wformat=2 \
-Winit-self \
-Wmissing-include-dirs \
-Wshift-overflow=2 \
-Wstrict-overflow=3 \
-Walloc-zero \
-Wduplicated-cond \
-Wfloat-equal \
-Wundef \
-Wshadow \
-Wpointer-arith \
-Wbad-function-cast \
-Wwrite-strings \
-Wdate-time \
-Wsign-conversion \
-Wfloat-conversion \
-Wlogical-op \
-Waggregate-return \
-Wstrict-prototypes \
-Wold-style-definition \
-Wmissing-prototypes \
-Wmissing-declarations \
-Wredundant-decls \
\
-Wc99-compat \
-Wc11-extensions \
-Wc2x-compat \
-Wc2x-extensions \
-Wpre-c2x-compat \
-Warray-bounds-pointer-arithmetic \
-Wassign-enum \
-Wconditional-uninitialized \
-Wdocumentation \
-Wduplicate-enum \
-Wempty-translation-unit \
-Wflexible-array-extensions \
-Wmissing-variable-declarations \
-Wnewline-eof \
-Wshift-sign-overflow \
-Wstring-conversion
2007-12-08 22:42:33 +00:00
do
AC_MSG_CHECKING([if $CC accepts $NEW_FLAG])
OLD_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS $NEW_FLAG -Werror"
AC_COMPILE_IFELSE([AC_LANG_SOURCE(
[[void foo(void); void foo(void) { }]])], [
AM_CFLAGS="$AM_CFLAGS $NEW_FLAG"
2007-12-08 22:42:33 +00:00
AC_MSG_RESULT([yes])
], [
AC_MSG_RESULT([no])
])
CFLAGS="$OLD_CFLAGS"
2007-12-08 22:42:33 +00:00
done
AC_ARG_ENABLE([werror],
AS_HELP_STRING([--enable-werror], [Enable -Werror to abort
2007-12-08 22:42:33 +00:00
compilation on all compiler warnings.]),
[], [enable_werror=no])
if test "x$enable_werror" = "xyes"; then
AM_CFLAGS="$AM_CFLAGS -Werror"
2007-12-08 22:42:33 +00:00
fi
])
2007-12-08 22:42:33 +00:00
###############################################################################
# Create the makefiles and config.h
###############################################################################
echo
# Don't build the lib directory at all if we don't need any replacement
# functions.
AM_CONDITIONAL([COND_GNULIB], test -n "$LIBOBJS")
# Add default AM_CFLAGS.
AC_SUBST([AM_CFLAGS])
# This is needed for src/scripts.
xz=`echo xz | sed "$program_transform_name"`
AC_SUBST([xz])
2007-12-08 22:42:33 +00:00
AC_CONFIG_FILES([
Makefile
po/Makefile.in
lib/Makefile
src/Makefile
src/liblzma/Makefile
src/liblzma/api/Makefile
src/xz/Makefile
src/xzdec/Makefile
src/lzmainfo/Makefile
2007-12-08 22:42:33 +00:00
src/scripts/Makefile
tests/Makefile
debug/Makefile
2007-12-08 22:42:33 +00:00
])
AC_CONFIG_FILES([src/scripts/xzdiff], [chmod +x src/scripts/xzdiff])
AC_CONFIG_FILES([src/scripts/xzgrep], [chmod +x src/scripts/xzgrep])
AC_CONFIG_FILES([src/scripts/xzmore], [chmod +x src/scripts/xzmore])
AC_CONFIG_FILES([src/scripts/xzless], [chmod +x src/scripts/xzless])
2007-12-08 22:42:33 +00:00
AC_OUTPUT
# Some warnings
if test x$tuklib_cv_physmem_method = xunknown; then
echo
echo "WARNING:"
echo "No supported method to detect the amount of RAM."
echo "Consider using --enable-assume-ram (if you didn't already)"
echo "or make a patch to add support for this operating system."
fi
if test x$tuklib_cv_cpucores_method = xunknown; then
echo
echo "WARNING:"
echo "No supported method to detect the number of CPU cores."
fi
if test "x$enable_threads$enable_small$have_func_attribute_constructor" \
= xnoyesno; then
echo
echo "NOTE:"
echo "liblzma will be thread-unsafe due to the combination"
echo "of --disable-threads --enable-small when using a compiler"
echo "that doesn't support __attribute__((__constructor__))."
fi