Re: info frame

Mark Kettenis
2006-04-17T10:54:11Z

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> Date: Mon, 17 Apr 2006 13:35:54 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> CC: nickrob@snap.net.nz, gdb@sources.redhat.com
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> > Date: Mon, 17 Apr 2006 10:58:43 +0200 (CEST)
> > From: Mark Kettenis <mark.kettenis@xs4all.nl>
> > CC: nickrob@snap.net.nz, gdb@sources.redhat.com
> >
> > > > Yes, current GDB uses the convention that the frame address is the
> > > > Canonical Frame Address (CFA) as used by the DWARF 2 Call Frame Info
> > > > (CFI).
> > >
> > > Does this mean that, if the debug info is stabs or something other
> > > than DWARF 2, a different frame address will be displayed for the same
> > > code?
> >
> > No. All the different unwinders use the same convention.
>
> Don't you glean the information from the debug info? At least for
> functions that violate the normal call frame, you probably must, no?

The only debug format that contains the information is DWARF 2/3. The
other unwinders all code scanning techniques to find out the CFA.
Those have been adapted to match the CFA as used by GCC.