#serial 6 dnl From Jim Meyering. dnl Determine whether realloc works when both arguments are 0. dnl If it doesn't, arrange to use the replacement function. dnl AC_DEFUN([jm_FUNC_REALLOC], [ dnl xmalloc.c requires that this symbol be defined so it doesn't dnl mistakenly use a broken realloc -- as it might if this test were omitted. AC_DEFINE(HAVE_DONE_WORKING_REALLOC_CHECK, 1, [Define if the realloc check has been performed. ]) AC_CACHE_CHECK([whether realloc(0,0) returns a non-NULL pointer], jm_cv_func_working_realloc, [AC_TRY_RUN([ char *realloc (); int main () { exit (realloc (0, 0) ? 0 : 1); } ], jm_cv_func_working_realloc=yes, jm_cv_func_working_realloc=no, dnl When crosscompiling, assume realloc(0,0) returns NULL. jm_cv_func_working_realloc=no) ]) if test $jm_cv_func_working_realloc = no; then AC_LIBOBJ(realloc) AC_DEFINE(realloc, rpl_realloc, [Define to rpl_realloc if the replacement function should be used.]) fi ])