Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* frame.c (get_prev_frame_1) <UNWIND_INNER_ID>: New variables
this_pc_in_block, morestack_msym and morestack_name. Check for
"__morestack" minimal symbol there.
gdb/testsuite/
* gdb.base/morestack.exp: New file.
* gdb.base/morestack.c: New file.