http://sourceware.org/ml/gdb-patches/2013-07/msg00059.html

gdb/ChangeLog

        * stack.c (read_frame_arg): No longer fetch lazy values.
        * value.c (value_optimized_out): If the value is not already
        marked optimized out, and is lazy then fetch it.
        (value_primitive_field): Move optimized out check to later in the
        function, after we have loaded any lazy values.
        (value_fetch_lazy): Use optimized out flag directly rather than
        calling optimized_out method.

gdb/testsuite/ChangeLog

        * gdb.dwarf2/dw2-reg-undefined.exp: New file.
        * gdb.dwarf2/dw2-reg-undefined.c: Likewise.
        * gdb.dwarf2/dw2-reg-undefined.S: Likewise.