[Crash-utility] resolve symbols: sial.so vs eppic.so

[Sebastian Ott]

On Thu, 6 Sep 2012, Luc Chouinard wrote:
> Pulled trigger too quick.
> Here's the variable you should set.
> 
> export EPPIC_LEGACY_MODE=1
> 

Ok thanks. In addition to that I just found out that one can use
"#ifdef eppic" inside scripts.

Regards,
Sebastian

> If a more granular way of switching from old to new mode is needed, we
> should discuss it.
> 
>    -Luc
> 
> > -----Original Message-----
> > From: Luc Chouinard
> > Sent: Thursday, September 06, 2012 9:01 AM
> > To: 'Sebastian Ott'; Dave Anderson
> > Cc: crash-utility at redhat.com; holzheu at linux.vnet.ibm.com
> > Subject: RE: resolve symbols: sial.so vs eppic.so
> > 
> > Eppic now resolves symbols to their real typed instances directly.
> > No need to know and cast from symbol address anymore.
> > For backward compatibility, you can define environment variable
> > 
> > > -----Original Message-----
> > > From: Sebastian Ott [mailto:sebott at linux.vnet.ibm.com]
> > > Sent: Thursday, September 06, 2012 6:50 AM
> > > To: Luc Chouinard; Dave Anderson
> > > Cc: crash-utility at redhat.com; holzheu at linux.vnet.ibm.com
> > > Subject: resolve symbols: sial.so vs eppic.so
> > >
> > > The way symbols are resolved in sial scripts is different between
> > > sial.so and eppic.so. A symbol resolves to the address of the symbol
> > > using sial.so and to the memory content using eppic.so.
> > >
> > > In crash 6.0.9 I got e.g.:
> > >
> > > crash> sym dev_kobj
> > > 979138 (b) dev_kobj
> > > crash> rd dev_kobj
> > >           979138:  0000000174c9aac0                    ....t...
> > > crash> dev_kobj
> > > dev_kobj = $3 = (struct kobject *) 0x174c9aac0
> > >
> > > Using a sial script:
> > >
> > > crash> !cat foo.sial
> > > string foo_help()  { return ""; }
> > > string foo_opt()   { return ""; }
> > > string foo_usage() { return ""; }
> > >
> > > int foo()
> > > {
> > >   printf("0x%x\n", dev_kobj);
> > >
> > >   return 1;
> > > }
> > >
> > > ./eppic.so: shared object loaded
> > > crash> load foo.sial
> > > crash> foo
> > > 0x74c9aac0
> > >
> > > ./sial.so: shared object loaded
> > > crash> load foo.sial
> > > crash> foo
> > > 0x979138
> > >
> > > Is this an intentional change or a bug?
> > >
> > > Regards,
> > > Sebastian
> 
>