Re: [RFA] epilogue unwinder for i386 (reverse 1/2)

Michael Snyder
2009-07-13T19:35:05Z

drow@false.org wrote:
> On Sun, Jul 12, 2009 at 10:42:54AM -0700, Michael Snyder wrote:
>> Daniel, a heads-up -- this seems to break your test "i386-signal.exp".
>
> When checked in, it's our test. I don't think it's appropriate to
> commit a patch which causes testsuite regressions.

You're right, bad judgement call on my part.
I'll take it out again until this is resolved.

The issue is, the test contains a hand-coded artificial signal
frame/handler consisting of a single "ret" instruction.

My new epilogue unwinder recognizes the "ret", so it lays
claim to the frame before the dwarf unwinder has a chance.

It still does a proper backtrace, but of course it doesn't
show the <signal handler> tag, it just shows the function name.

What do you think? Could we maybe add a nop here or something?
I don't understand the details well enough to speculate.

Michael