autoconf attempts to execute a stdlib that it only compiled, and did not link. I originally found this bug in the ./i686-pc-linux-gnu/libiberty/configure in gcc 3.4.1, and gcc unfortunately fails to provide the configure.in that they used to generate their configure.
--- ./lib/autoconf/headers.m4 Thu Sep 25 02:28:51 2003 +++ ./lib/autoconf/headers.m4.new Sun Sep 4 19:40:24 2005 @@ -568,7 +568,7 @@ AC_DEFUN([AC_HEADER_STDC], [AC_CACHE_CHECK(for ANSI C header files, ac_cv_header_stdc, -[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stdlib.h> +[AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdlib.h> #include <stdarg.h> #include <string.h> #include <float.h>
