3 dnl Process this file with autoconf to produce a configure script.
5 dnl Minor upgrades (compatible ABI): increment the package version
6 dnl (third field in two places below) and set the PNGLIB_RELEASE
9 dnl Major upgrades (incompatible ABI): increment the package major
10 dnl version (second field, or first if desired), set the minor
11 dnl to 0, set PNGLIB_MAJOR below *and* follow the instructions in
12 dnl Makefile.am to upgrade the package name.
14 dnl This is here to prevent earlier autoconf from being used, it
15 dnl should not be necessary to regenerate configure if the time
16 dnl stamps are correct
19 dnl Version number stuff here:
21 AC_INIT([libpng],[1.6.21],[png-mng-implement@lists.sourceforge.net])
22 AC_CONFIG_MACRO_DIR([scripts])
24 # libpng does not follow GNU file name conventions (hence 'foreign')
25 # color-tests requires automake 1.11 or later
26 # silent-rules requires automake 1.11 or later
27 # dist-xz requires automake 1.11 or later
28 # 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
29 # 1.13 is required for parallel tests
30 AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules subdir-objects])
31 # The following line causes --disable-maintainer-mode to be the default to
32 # configure, this is necessary because libpng distributions cannot rely on the
33 # time stamps of the autotools generated files being correct
36 dnl configure.ac and Makefile.am expect automake 1.11.2 or a compatible later
37 dnl version; aclocal.m4 will generate a failure if you use a prior version of
38 dnl automake, so the following is not necessary (and is not defined anyway):
39 dnl AM_PREREQ([1.11.2])
40 dnl stop configure from automagically running automake
47 dnl End of version number stuff
49 AC_CONFIG_SRCDIR([pngget.c])
50 AC_CONFIG_HEADERS([config.h])
52 # Checks for programs.
63 dnl libtool/libtoolize; version 2.4.2 is the tested version, this or any
64 dnl compatible later version may be used
68 # Some awks crash when confronted with pnglibconf.dfa, do a test run now
69 # to make sure this doesn't happen
70 AC_MSG_CHECKING([that AWK works])
71 if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
72 ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
73 ${srcdir}/pngusr.dfa 1>&2
77 AC_MSG_FAILURE([failed], 1)
80 # This is a remnant of the old cc -E validation, where it may have been
81 # necessary to use a different preprocessor for .dfn files
85 # -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
86 # checks the compiler with a program that generates a warning), add the
87 # following option to deal with this
89 [additional flags for the C compiler, use this for options that would]
90 [cause configure itself to fail])
92 AS_HELP_STRING([[[--enable-werror[=OPT]]]],
93 [Pass -Werror or the given argument to the compiler if it is supported]),
94 [test "$enable_werror" = "yes" && enable_werror="-Werror"
95 if test "$enable_werror" != "no"; then
97 CFLAGS="$enable_werror $CFLAGS"
98 AC_MSG_CHECKING([if the compiler allows $enable_werror])
101 [int main(int argc, char **argv){]
102 [return argv[argc-1][0];]
105 PNG_COPTS="$PNG_COPTS $enable_werror",
110 # Checks for header files.
113 # Checks for typedefs, structures, and compiler characteristics.
119 # Checks for library functions.
121 AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
122 AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
123 AC_ARG_WITH(zlib-prefix,
124 AS_HELP_STRING([[[--with-zlib-prefix]]],
125 [prefix that may have been used in installed zlib]),
126 [ZPREFIX=${withval}],
128 AC_CHECK_LIB(z, zlibVersion, ,
129 AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
131 # The following is for pngvalid, to ensure it catches FP errors even on
132 # platforms that don't enable FP exceptions, the function appears in the math
133 # library (typically), it's not an error if it is not found.
134 AC_CHECK_LIB([m], [feenableexcept])
135 AC_CHECK_FUNCS([feenableexcept])
137 AC_MSG_CHECKING([if using Solaris linker])
138 SLD=`$LD --version 2>&1 | grep Solaris`
146 AM_CONDITIONAL(HAVE_SOLARIS_LD, test "$have_solaris_ld" = "yes")
148 AC_MSG_CHECKING([if libraries can be versioned])
149 # Special case for PE/COFF platforms: ld reports
150 # support for version-script, but doesn't actually
151 # DO anything with it.
153 *cygwin* | *mingw32* | *interix* )
154 have_ld_version_script=no
159 if test "$have_solaris_ld" = "yes"; then
160 GLD=`$LD --help < /dev/null 2>&1 | grep 'M mapfile'`
162 GLD=`$LD --help < /dev/null 2>/dev/null | grep version-script`
166 have_ld_version_script=yes
169 have_ld_version_script=no
171 AC_MSG_WARN(*** You have not enabled versioned symbols.)
176 AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
178 if test "$have_ld_version_script" = "yes"; then
179 AC_MSG_CHECKING([for symbol prefix])
180 SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
181 | ${CPP-${CC-gcc} -E} - 2>&1 \
182 | ${EGREP-grep} "^PREFIX=" \
183 | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
184 AC_SUBST(SYMBOL_PREFIX)
185 AC_MSG_RESULT($SYMBOL_PREFIX)
188 # Substitutions for .in files
189 AC_SUBST(PNGLIB_VERSION)
190 AC_SUBST(PNGLIB_MAJOR)
191 AC_SUBST(PNGLIB_MINOR)
192 AC_SUBST(PNGLIB_RELEASE)
194 # Additional arguments (and substitutions)
195 # Allow the pkg-config directory to be set
196 AC_ARG_WITH(pkgconfigdir,
197 AS_HELP_STRING([[[--with-pkgconfigdir]]],
198 [Use the specified pkgconfig dir (default is libdir/pkgconfig)]),
199 [pkgconfigdir=${withval}],
200 [pkgconfigdir='${libdir}/pkgconfig'])
202 AC_SUBST([pkgconfigdir])
203 AC_MSG_NOTICE([[pkgconfig directory is ${pkgconfigdir}]])
205 # Make the *-config binary config scripts optional
206 AC_ARG_WITH(binconfigs,
207 AS_HELP_STRING([[[--with-binconfigs]]],
208 [Generate shell libpng-config scripts as well as pkg-config data]
209 [@<:@default=yes@:>@]),
210 [if test "${withval}" = no; then
212 AC_MSG_NOTICE([[libpng-config scripts will not be built]])
214 binconfigs='${binconfigs}'
216 [binconfigs='${binconfigs}'])
217 AC_SUBST([binconfigs])
219 # Support for prefixes to the API function names; this will generate defines
220 # at the start of the build to rename exported library functions
221 AC_ARG_WITH(libpng-prefix,
222 AS_HELP_STRING([[[--with-libpng-prefix]]],
223 [prefix libpng exported function (API) names with the given value]),
224 [if test "${withval:-no}" != "no"; then
225 AC_SUBST([PNG_PREFIX], [${withval}])
227 AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
229 # Control over what links are made for installed files. Versioned files are
230 # always installed, when the following options are turned on corresponding
231 # unversioned links are also created (normally as symbolic links):
232 AC_ARG_ENABLE([unversioned-links],
233 AS_HELP_STRING([[[--enable-unversioned-links]]],
234 [Installed libpng header files are placed in a versioned subdirectory]
235 [and installed libpng library (including DLL) files are versioned.]
236 [If this option is enabled unversioned links will be created pointing to]
237 [the corresponding installed files. If you use libpng.pc or]
238 [libpng-config for all builds you do not need these links, but if you]
239 [compile programs directly they will typically #include <png.h> and]
240 [link with -lpng; in that case you need the links.]
241 [The links can be installed manually using 'make install-header-links']
242 [and 'make install-library-links' and can be removed using the]
243 [corresponding uninstall- targets. If you do enable this option every]
244 [libpng 'make install' will recreate the links to point to the just]
245 [installed version of libpng. The default is to create the links;]
246 [use --disable-unversioned-links to change this]))
248 # The AM_CONDITIONAL test is written so that the default is enabled;
249 # --disable-unversioned-links must be given to turn the option off.
250 AM_CONDITIONAL([DO_INSTALL_LINKS],[test "$enable_unversioned_links" != "no"])
252 AC_ARG_ENABLE([unversioned-libpng-pc],
253 AS_HELP_STRING([[[--enable-unversioned-libpng-pc]]],
254 [Install the configuration file 'libpng.pc' as a link to the versioned]
255 [version. This is done by default - use --disable-unversioned-libpng-pc]
257 AM_CONDITIONAL([DO_INSTALL_LIBPNG_PC],
258 [test "$enable_unversioned_libpng_pc" != "no"])
260 AC_ARG_ENABLE([unversioned-libpng-config],
261 AS_HELP_STRING([[[--enable-unversioned-libpng-config]]],
262 [Install the configuration file 'libpng-config' as a link to the]
263 [versioned version. This is done by default - use]
264 [--disable-unversioned-libpng-config to change this.]))
265 AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
266 [test "$enable_unversioned_libpng_config" != "no"])
268 # HOST SPECIFIC OPTIONS
269 # =====================
274 # ARM NEON (SIMD) support.
276 AC_ARG_ENABLE([arm-neon],
277 AS_HELP_STRING([[[--enable-arm-neon]]],
278 [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
279 [no/off: disable the optimizations; check: use internal checking code]
280 [(deprecated and poorly supported); api: disable by default, enable by]
281 [a call to png_set_option; yes/on: turn on unconditionally.]
282 [If not specified: determined by the compiler.]),
283 [case "$enableval" in
285 # disable the default enabling on __ARM_NEON__ systems:
286 AC_DEFINE([PNG_ARM_NEON_OPT], [0],
287 [Disable ARM Neon optimizations])
288 # Prevent inclusion of the assembler files below:
291 AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
292 [Check for ARM Neon support at run-time]);;
294 AC_DEFINE([PNG_ARM_NEON_API_SUPPORTED], [],
295 [Turn on ARM Neon optimizations at run-time]);;
297 AC_DEFINE([PNG_ARM_NEON_OPT], [2],
298 [Enable ARM Neon optimizations])
299 AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api', if]
300 [you want the optimizations unconditionally pass -mfpu=neon]
301 [to the compiler.]);;
303 AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
306 # Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
307 # where ARM optimizations were explicitly requested (this allows a fallback if a
308 # future host CPU does not match 'arm*')
310 AM_CONDITIONAL([PNG_ARM_NEON],
311 [test "$enable_arm_neon" != 'no' &&
314 *) test "$enable_arm_neon" != '';;
317 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
319 # Config files, substituting as above
320 AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
321 AC_CONFIG_FILES([libpng-config:libpng-config.in],
322 [chmod +x libpng-config])