To clarify a few things

[Rafał Mużyło]

OK, in my first mail I did missunderstand quite a few things.
First I should add that the system is GNU/Linux. So now my question
changes to why does AC_LIBTOOL_SYS_DYNAMIC_LINKER create
sys_lib_dlsearch_path_spec in following way
  if test -f /etc/ld.so.conf; then
      lt_ld_extra=`awk '/^include / { system(sprintf("cd /etc; cat %s
          2>/dev/null"
          , \[$]2)); skip = 1; } { if (!skip) print \[$]0; skip = 0; }' <
          /etc/ld.so.conf 
          | $SED -e 's/#.*//;s/[:,        ]/ /g;s/=[^=]*$//;s/=[^= ]* /
          /g;/^$/d' | tr '\n
          ' ' '`
        sys_lib_dlsearch_path_spec="/lib /usr/lib $lt_ld_extra"
  fi

and does not allow user to modify this behaviour in any way, in example
doesn't add LD_LIBRARY_PATH to sys_lib_dlsearch_path_spec, as those
directories are not to be hardcoded. I'm talking about cases, when I'm
installing a library only for myself, when I'm not root, but still don't
want to have hardcoded paths in the library (as I'm setting
LD_LIBRARY_PATH in .bash_profile anyway).
So is there any sane way of doing this, short of manually adding a
modified AC_LIBTOOL_SYS_DYNAMIC_LINKER macro to every compiled package.