Re: [PATCH] Fix agent code generate bug of ref

Tom Tromey
2013-03-12T14:17:15Z

>>>>> "Hui" == Hui Zhu <teawater@gmail.com> writes:

Hui> Sorry for my misunderstand in your mail. Accord to discussion with
Hui> Yao in IRC. I merge 2 patches together.
Hui> And I found that gdb_assert of access_memory. It should use nbytes.

Thanks for doing this.

Hui> 2013-03-12 Yao Qi <yao@codesourcery.com>
Hui> Hui Zhu <hui_zhu@mentor.com>
Hui> * dwarf2loc.c (access_memory): Change nbits to nbytes in gdb_assert.
Hui> (dwarf2_compile_expr_to_ax): Call access_memory in DW_OP_deref and
Hui> DW_OP_deref_size.

Hui> + gdb_assert (nbytes > 0 && nbytes <= sizeof (LONGEST));

Hui> - default:
Hui> - /* Note that get_DW_OP_name will never return
Hui> - NULL here. */
Hui> - error (_("Unsupported size %d in %s"),
Hui> - size, get_DW_OP_name (op));
Hui> - }

I think we need a sanity check before calling access_memory.
Otherwise, bad DWARF will be able to crash gdb.
The patch is ok with that change.

Tom