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AC_CHECK_TYPEDEF_(TYPEDEF, HEADER [, ACTION-IF-FOUND [,
ACTION-IF-NOT-FOUND ]])
check if the given typedef-name is recognized as a type. The trick is to use a sizeof(TYPEDEF) and see if the compiler is happy with that.
this can be thought of as a mixture of AC_CHECK_TYPE(TYPEDEF,DEFAULT) and AC_CHECK_LIB(LIBRARY,FUNCTION,ACTION-IF-FOUND,ACTION-IF-NOT-FOUND)
a convenience macro AC_CHECK_TYPEDEF_ is provided that will not emit any message to the user - it just executes one of the actions.
Guido Draheim <guidod@gmx.de>
2005-12-18
AC_DEFUN([AC_CHECK_TYPEDEF_],
[dnl
ac_lib_var=`echo $1['_']$2 | sed 'y%./+-%__p_%'`
AC_CACHE_VAL(ac_cv_lib_$ac_lib_var,
[ eval "ac_cv_type_$ac_lib_var='not-found'"
ac_cv_check_typedef_header=`echo ifelse([$2], , stddef.h, $2)`
AC_TRY_COMPILE( [#include <$ac_cv_check_typedef_header>],
[int x = sizeof($1); x = x;],
eval "ac_cv_type_$ac_lib_var=yes" ,
eval "ac_cv_type_$ac_lib_var=no" )
if test `eval echo '$ac_cv_type_'$ac_lib_var` = "no" ; then
ifelse([$4], , :, $4)
else
ifelse([$3], , :, $3)
fi
])])
dnl AC_CHECK_TYPEDEF(TYPEDEF, HEADER [, ACTION-IF-FOUND,
dnl [, ACTION-IF-NOT-FOUND ]])
AC_DEFUN([AC_CHECK_TYPEDEF],
[dnl
AC_MSG_CHECKING([for $1 in $2])
AC_CHECK_TYPEDEF_($1,$2,AC_MSG_RESULT(yes),AC_MSG_RESULT(no))dnl
])