Re: [rtl] RTL fails to boot when compiled with -fno-omit-frame-pointers

[Felix Radensky <felix@allot.com>]

yodaiken@fsmlabs.com wrote:

> On Thu, Oct 28, 1999 at 01:21:07PM +0200, Felix Radensky wrote:
> > Hi,
> >
> > I've applied rtl v1.3 to linux-2.0.37 and changed
> > CFLAGS to -Wall -Wstrict-prototypes -O2 -fno-omit-frame-pointer
> > -fno-strength-reduce
> > The difference is -fno-omit-frame-pointer flag, that is needed for
> > proper stack trace
> > debugging. The kernel just cannot boot. The normal kernel boots fine.
> > Any ideas would
> > be greatly appreciated.
>
> Do you mean that the normal kernel boots fine when compiled with those
> flags?
>
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Exactly. Some kernel debuggers require kernel to be compiled with -g
-fno-omit-frame-pointers
in order for stack backtracing to work properly. This is true for kdb
(http://reality.sgi.com/slurn_engr/)
and ikd (ftp://e-mind.com/pub/andrea/ikd/). GCC-HOWTO also says that
-fno-omit-frame-pointers
should be used for debugging.
Normal kernels (I've tried 2.0.35, 2.0.36 & 2.0.37 ) when compiled with
this flag (gcc-2.7.2.3) boot
ok. With kernels patched with rtl (v1.2 & v1.3) the system prints
"Loading linux ..." and reboots immediately.

By the way, 2.2.13 kernel patched with rtl v2.0 and compiled with
-fno-omit-frame-pointers has no problems booting. But since we use
2.0.x series kernel, it would be nice to have rtl working as expected
with these kernels also. 

Thank you.

Felix.
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