Bug 10224

Summary:	Please add dwarf3 DW_OP_call_frame_cfa
Product:	gdb	Reporter:	Richard Henderson <rth>
Component:	backtrace	Assignee:	Tom Tromey <tromey>
Status:	RESOLVED FIXED
Severity:	enhancement	CC:	gdb-prs, jan, tromey
Priority:	P2
Version:	unknown
Target Milestone:	7.0
Host:		Target:
Build:		Last reconfirmed:	2009-06-02 23:27:09
Attachments:	quick hack to make gcc generate DW_OP_call_frame_cfa

Description Richard Henderson 2009-06-01 16:14:05 UTC

Currently GCC has to describe the CFA twice, once for the unwind info
and once in the form of location lists for DW_AT_frame_base.  This
dwarf3 opcode allows DW_AT_frame_base to essentially reference the
unwind info definition.

Comment 1 Tom Tromey 2009-06-02 21:31:01 UTC

What is the simplest way to test a patch implementing this?

Comment 2 Richard Henderson 2009-06-02 23:11:26 UTC

We'll whip up a patch to generate the opcode, then ...

Probably to watch the value of a function argument on
the stack, while stepping through the prologue of a function.

Comment 3 Tom Tromey 2009-06-02 23:27:09 UTC

Sounds good.

I have a gdb patch; attach the gcc patch here and I will give it a try.

Comment 4 Richard Henderson 2009-06-03 00:07:22 UTC

Created attachment 3979 [details]
quick hack to make gcc generate DW_OP_call_frame_cfa

I'm not sure off-hand what conditional I should really be using,
but no conditional at all will work for testing.  =)

Comment 5 Tom Tromey 2009-09-14 15:58:27 UTC

I checked in the fix.