cannam@154: dnl Macros to check the presence of generic (non-typed) symbols.
cannam@154: dnl Copyright (c) 2006-2007 Diego Pettenò <flameeyes@gmail.com>
cannam@154: dnl Copyright (c) 2006-2007 xine project
cannam@154: dnl
cannam@154: dnl This program is free software; you can redistribute it and/or modify
cannam@154: dnl it under the terms of the GNU General Public License as published by
cannam@154: dnl the Free Software Foundation; either version 2, or (at your option)
cannam@154: dnl any later version.
cannam@154: dnl
cannam@154: dnl This program is distributed in the hope that it will be useful,
cannam@154: dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@154: dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@154: dnl GNU General Public License for more details.
cannam@154: dnl
cannam@154: dnl You should have received a copy of the GNU General Public License
cannam@154: dnl along with this program; if not, write to the Free Software
cannam@154: dnl Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
cannam@154: dnl 02110-1301, USA.
cannam@154: dnl
cannam@154: dnl As a special exception, the copyright owners of the
cannam@154: dnl macro gives unlimited permission to copy, distribute and modify the
cannam@154: dnl configure scripts that are the output of Autoconf when processing the
cannam@154: dnl Macro. You need not follow the terms of the GNU General Public
cannam@154: dnl License when using or distributing such scripts, even though portions
cannam@154: dnl of the text of the Macro appear in them. The GNU General Public
cannam@154: dnl License (GPL) does govern all other use of the material that
cannam@154: dnl constitutes the Autoconf Macro.
cannam@154: dnl
cannam@154: dnl This special exception to the GPL applies to versions of the
cannam@154: dnl Autoconf Macro released by this project. When you make and
cannam@154: dnl distribute a modified version of the Autoconf Macro, you may extend
cannam@154: dnl this special exception to the GPL to apply to your modified version as
cannam@154: dnl well.
cannam@154: 
cannam@154: dnl Check if the flag is supported by compiler
cannam@154: dnl CC_CHECK_CFLAGS_SILENT([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
cannam@154: 
cannam@154: AC_DEFUN([CC_CHECK_CFLAGS_SILENT], [
cannam@154:   AC_CACHE_VAL(AS_TR_SH([cc_cv_cflags_$1]),
cannam@154:     [ac_save_CFLAGS="$CFLAGS"
cannam@154:      CFLAGS="$CFLAGS $1"
cannam@154:      AC_LINK_IFELSE([AC_LANG_SOURCE([int main() { return 0; }])],
cannam@154:        [eval "AS_TR_SH([cc_cv_cflags_$1])='yes'"],
cannam@154:        [eval "AS_TR_SH([cc_cv_cflags_$1])='no'"])
cannam@154:      CFLAGS="$ac_save_CFLAGS"
cannam@154:     ])
cannam@154: 
cannam@154:   AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
cannam@154:     [$2], [$3])
cannam@154: ])
cannam@154: 
cannam@154: dnl Check if the flag is supported by compiler (cacheable)
cannam@154: dnl CC_CHECK_CFLAGS([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
cannam@154: 
cannam@154: AC_DEFUN([CC_CHECK_CFLAGS], [
cannam@154:   AC_CACHE_CHECK([if $CC supports $1 flag],
cannam@154:     AS_TR_SH([cc_cv_cflags_$1]),
cannam@154:     CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
cannam@154:   )
cannam@154: 
cannam@154:   AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
cannam@154:     [$2], [$3])
cannam@154: ])
cannam@154: 
cannam@154: dnl CC_CHECK_CFLAG_APPEND(FLAG, [action-if-found], [action-if-not-found])
cannam@154: dnl Check for CFLAG and appends them to CFLAGS if supported
cannam@154: AC_DEFUN([CC_CHECK_CFLAG_APPEND], [
cannam@154:   AC_CACHE_CHECK([if $CC supports $1 flag],
cannam@154:     AS_TR_SH([cc_cv_cflags_$1]),
cannam@154:     CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
cannam@154:   )
cannam@154: 
cannam@154:   AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
cannam@154:     [CFLAGS="$CFLAGS $1"; $2], [$3])
cannam@154: ])
cannam@154: 
cannam@154: dnl CC_CHECK_CFLAGS_APPEND([FLAG1 FLAG2], [action-if-found], [action-if-not])
cannam@154: AC_DEFUN([CC_CHECK_CFLAGS_APPEND], [
cannam@154:   for flag in $1; do
cannam@154:     CC_CHECK_CFLAG_APPEND($flag, [$2], [$3])
cannam@154:   done
cannam@154: ])
cannam@154: 
cannam@154: dnl Check if the flag is supported by linker (cacheable)
cannam@154: dnl CC_CHECK_LDFLAGS([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
cannam@154: 
cannam@154: AC_DEFUN([CC_CHECK_LDFLAGS], [
cannam@154:   AC_CACHE_CHECK([if $CC supports $1 flag],
cannam@154:     AS_TR_SH([cc_cv_ldflags_$1]),
cannam@154:     [ac_save_LDFLAGS="$LDFLAGS"
cannam@154:      LDFLAGS="$LDFLAGS $1"
cannam@154:      AC_LINK_IFELSE([AC_LANG_SOURCE([int main() { return 1; }])],
cannam@154:        [eval "AS_TR_SH([cc_cv_ldflags_$1])='yes'"],
cannam@154:        [eval "AS_TR_SH([cc_cv_ldflags_$1])="])
cannam@154:      LDFLAGS="$ac_save_LDFLAGS"
cannam@154:     ])
cannam@154: 
cannam@154:   AS_IF([eval test x$]AS_TR_SH([cc_cv_ldflags_$1])[ = xyes],
cannam@154:     [$2], [$3])
cannam@154: ])
cannam@154: 
cannam@154: dnl define the LDFLAGS_NOUNDEFINED variable with the correct value for
cannam@154: dnl the current linker to avoid undefined references in a shared object.
cannam@154: AC_DEFUN([CC_NOUNDEFINED], [
cannam@154:   dnl We check $host for which systems to enable this for.
cannam@154:   AC_REQUIRE([AC_CANONICAL_HOST])
cannam@154: 
cannam@154:   case $host in
cannam@154:      dnl FreeBSD (et al.) does not complete linking for shared objects when pthreads
cannam@154:      dnl are requested, as different implementations are present; to avoid problems
cannam@154:      dnl use -Wl,-z,defs only for those platform not behaving this way.
cannam@154:      *-freebsd* | *-openbsd*) ;;
cannam@154:      *)
cannam@154:         dnl First of all check for the --no-undefined variant of GNU ld. This allows
cannam@154:         dnl for a much more readable commandline, so that people can understand what
cannam@154:         dnl it does without going to look for what the heck -z defs does.
cannam@154:         for possible_flags in "-Wl,--no-undefined" "-Wl,-z,defs"; do
cannam@154:           CC_CHECK_LDFLAGS([$possible_flags], [LDFLAGS_NOUNDEFINED="$possible_flags"])
cannam@154: 	  break
cannam@154:         done
cannam@154: 	;;
cannam@154:   esac
cannam@154: 
cannam@154:   AC_SUBST([LDFLAGS_NOUNDEFINED])
cannam@154: ])
cannam@154: 
cannam@154: dnl Check for a -Werror flag or equivalent. -Werror is the GCC
cannam@154: dnl and ICC flag that tells the compiler to treat all the warnings
cannam@154: dnl as fatal. We usually need this option to make sure that some
cannam@154: dnl constructs (like attributes) are not simply ignored.
cannam@154: dnl
cannam@154: dnl Other compilers don't support -Werror per se, but they support
cannam@154: dnl an equivalent flag:
cannam@154: dnl  - Sun Studio compiler supports -errwarn=%all
cannam@154: AC_DEFUN([CC_CHECK_WERROR], [
cannam@154:   AC_CACHE_CHECK(
cannam@154:     [for $CC way to treat warnings as errors],
cannam@154:     [cc_cv_werror],
cannam@154:     [CC_CHECK_CFLAGS_SILENT([-Werror], [cc_cv_werror=-Werror],
cannam@154:       [CC_CHECK_CFLAGS_SILENT([-errwarn=%all], [cc_cv_werror=-errwarn=%all])])
cannam@154:     ])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_CHECK_ATTRIBUTE], [
cannam@154:   AC_REQUIRE([CC_CHECK_WERROR])
cannam@154:   AC_CACHE_CHECK([if $CC supports __attribute__(( ifelse([$2], , [$1], [$2]) ))],
cannam@154:     AS_TR_SH([cc_cv_attribute_$1]),
cannam@154:     [ac_save_CFLAGS="$CFLAGS"
cannam@154:      CFLAGS="$CFLAGS $cc_cv_werror"
cannam@154:      AC_COMPILE_IFELSE([AC_LANG_SOURCE([$3])],
cannam@154:        [eval "AS_TR_SH([cc_cv_attribute_$1])='yes'"],
cannam@154:        [eval "AS_TR_SH([cc_cv_attribute_$1])='no'"])
cannam@154:      CFLAGS="$ac_save_CFLAGS"
cannam@154:     ])
cannam@154: 
cannam@154:   AS_IF([eval test x$]AS_TR_SH([cc_cv_attribute_$1])[ = xyes],
cannam@154:     [AC_DEFINE(
cannam@154:        AS_TR_CPP([SUPPORT_ATTRIBUTE_$1]), 1,
cannam@154:          [Define this if the compiler supports __attribute__(( ifelse([$2], , [$1], [$2]) ))]
cannam@154:          )
cannam@154:      $4],
cannam@154:     [$5])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_CONSTRUCTOR], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [constructor],,
cannam@154:     [extern void foo();
cannam@154:      void __attribute__((constructor)) ctor() { foo(); }],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_DESTRUCTOR], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [destructor],,
cannam@154:     [extern void foo();
cannam@154:      void __attribute__((destructor)) dtor() { foo(); }],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_FORMAT], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [format], [format(printf, n, n)],
cannam@154:     [void __attribute__((format(printf, 1, 2))) printflike(const char *fmt, ...) { fmt = (void *)0; }],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_FORMAT_ARG], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [format_arg], [format_arg(printf)],
cannam@154:     [char *__attribute__((format_arg(1))) gettextlike(const char *fmt) { fmt = (void *)0; }],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_VISIBILITY], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [visibility_$1], [visibility("$1")],
cannam@154:     [void __attribute__((visibility("$1"))) $1_function() { }],
cannam@154:     [$2], [$3])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_NONNULL], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [nonnull], [nonnull()],
cannam@154:     [void __attribute__((nonnull())) some_function(void *foo, void *bar) { foo = (void*)0; bar = (void*)0; }],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_UNUSED], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [unused], ,
cannam@154:     [void some_function(void *foo, __attribute__((unused)) void *bar);],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_SENTINEL], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [sentinel], ,
cannam@154:     [void some_function(void *foo, ...) __attribute__((sentinel));],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_DEPRECATED], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [deprecated], ,
cannam@154:     [void some_function(void *foo, ...) __attribute__((deprecated));],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_ALIAS], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [alias], [weak, alias],
cannam@154:     [void other_function(void *foo) { }
cannam@154:      void some_function(void *foo) __attribute__((weak, alias("other_function")));],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_MALLOC], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [malloc], ,
cannam@154:     [void * __attribute__((malloc)) my_alloc(int n);],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_PACKED], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [packed], ,
cannam@154:     [struct astructure { char a; int b; long c; void *d; } __attribute__((packed));
cannam@154:      char assert@<:@(sizeof(struct astructure) == (sizeof(char)+sizeof(int)+sizeof(long)+sizeof(void*)))-1@:>@;],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_CONST], [
cannam@154:   CC_CHECK_ATTRIBUTE(
cannam@154:     [const], ,
cannam@154:     [int __attribute__((const)) twopow(int n) { return 1 << n; } ],
cannam@154:     [$1], [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_FLAG_VISIBILITY], [
cannam@154:   AC_REQUIRE([CC_CHECK_WERROR])
cannam@154:   AC_CACHE_CHECK([if $CC supports -fvisibility=hidden],
cannam@154:     [cc_cv_flag_visibility],
cannam@154:     [cc_flag_visibility_save_CFLAGS="$CFLAGS"
cannam@154:      CFLAGS="$CFLAGS $cc_cv_werror"
cannam@154:      CC_CHECK_CFLAGS_SILENT([-fvisibility=hidden],
cannam@154: 	cc_cv_flag_visibility='yes',
cannam@154: 	cc_cv_flag_visibility='no')
cannam@154:      CFLAGS="$cc_flag_visibility_save_CFLAGS"])
cannam@154: 
cannam@154:   AS_IF([test "x$cc_cv_flag_visibility" = "xyes"],
cannam@154:     [AC_DEFINE([SUPPORT_FLAG_VISIBILITY], 1,
cannam@154:        [Define this if the compiler supports the -fvisibility flag])
cannam@154:      $1],
cannam@154:     [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_FUNC_EXPECT], [
cannam@154:   AC_REQUIRE([CC_CHECK_WERROR])
cannam@154:   AC_CACHE_CHECK([if compiler has __builtin_expect function],
cannam@154:     [cc_cv_func_expect],
cannam@154:     [ac_save_CFLAGS="$CFLAGS"
cannam@154:      CFLAGS="$CFLAGS $cc_cv_werror"
cannam@154:      AC_COMPILE_IFELSE([AC_LANG_SOURCE(
cannam@154:        [int some_function() {
cannam@154:         int a = 3;
cannam@154:         return (int)__builtin_expect(a, 3);
cannam@154: 	}])],
cannam@154:        [cc_cv_func_expect=yes],
cannam@154:        [cc_cv_func_expect=no])
cannam@154:      CFLAGS="$ac_save_CFLAGS"
cannam@154:     ])
cannam@154: 
cannam@154:   AS_IF([test "x$cc_cv_func_expect" = "xyes"],
cannam@154:     [AC_DEFINE([SUPPORT__BUILTIN_EXPECT], 1,
cannam@154:      [Define this if the compiler supports __builtin_expect() function])
cannam@154:      $1],
cannam@154:     [$2])
cannam@154: ])
cannam@154: 
cannam@154: AC_DEFUN([CC_ATTRIBUTE_ALIGNED], [
cannam@154:   AC_REQUIRE([CC_CHECK_WERROR])
cannam@154:   AC_CACHE_CHECK([highest __attribute__ ((aligned ())) supported],
cannam@154:     [cc_cv_attribute_aligned],
cannam@154:     [ac_save_CFLAGS="$CFLAGS"
cannam@154:      CFLAGS="$CFLAGS $cc_cv_werror"
cannam@154:      for cc_attribute_align_try in 64 32 16 8 4 2; do
cannam@154:         AC_COMPILE_IFELSE([AC_LANG_SOURCE([
cannam@154:           int main() {
cannam@154:             static char c __attribute__ ((aligned($cc_attribute_align_try))) = 0;
cannam@154:             return c;
cannam@154:           }])], [cc_cv_attribute_aligned=$cc_attribute_align_try; break])
cannam@154:      done
cannam@154:      CFLAGS="$ac_save_CFLAGS"
cannam@154:   ])
cannam@154: 
cannam@154:   if test "x$cc_cv_attribute_aligned" != "x"; then
cannam@154:      AC_DEFINE_UNQUOTED([ATTRIBUTE_ALIGNED_MAX], [$cc_cv_attribute_aligned],
cannam@154:        [Define the highest alignment supported])
cannam@154:   fi
cannam@154: ])