Re: [RFC] DW_CFA_restore handling causes memory fault

[Frederic RISS <frederic.riss@st.com>]

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On Fri, 2005-11-18 at 00:35 -0800, Jim Blandy wrote:
> Yes!  But --- I apologize for not noticing this from the beginning ---
> as I see your comment, it occurs to me that probably a call to
> 'complaint' would be better than just a comment.  Mark or Daniel can
> string me up if they feel this will yield another 'incomplete CFI
> data; unspecified blah blah blah' annoyance, but I think it's probably
> the right thing.

OK, third try attached. I mimiced the formatting of other complaints of
the file. I didn't put the complaint in the 'else' clause, but added a
check after the whole 'if', because an allocated register state isn't
necessarily set to a correct value.

Just a question: why are the i18n'ified strings formatted this way ?

>  If you're doing this as part of your paying
> job, then the assignment from STMicroelectronics already on file

That's the case.

> For the sourceware account, see
> http://sourceware.org/cgi-bin/pdw/ps_form.cgi.  List me as the person
> approving the request.

I'll do the request this evening (setting up the CVS access from work
will take some time, I'll use my home box for this patch.)

Thanks,
Fred.


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2005-11-17  Frédéric Riss  <frederic.riss@st.com>
        
                * dwarf2-frame.c: (execute_cfa_program): Don't access 
		past the allocated dwarf2_frame_state.initial.regs.


Index: dwarf2-frame.c
===================================================================
--- dwarf2-frame.c	(revision 98)
+++ dwarf2-frame.c	(working copy)
@@ -294,8 +294,16 @@
 	  gdb_assert (fs->initial.reg);
 	  reg = insn & 0x3f;
 	  dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1);
-	  fs->regs.reg[reg] = fs->initial.reg[reg];
+	  if (reg < fs->initial.num_regs)
+	    fs->regs.reg[reg] = fs->initial.reg[reg];
+	  else 
+	    fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED;
+
+	  if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED)
+	    complaint (&symfile_complaints, _("\
+incomplete CFI data; DW_CFA_restore of unspecified register state at 0x%s."),
+		       paddr (fs->pc));
 	}
       else
 	{