[U-Boot-Users] Using the abatron to debug an image in flash

[Wolfgang Denk]

Dear Mark,

in message <9901EE1E8F8BD3119109009027A1B5F596AE40 at DIGINET2> you wrote:
> 
> (gdb) step
> 221         immr->im_fcc[CONFIG_ETHER_INDEX-1].fcc_fpsmr = CFG_FCC_PSMR | 
> FCC_PSMR_ENCRC;
> (gdb) step
> 213         immr->im_cpmux.cmx_fcr = (immr->im_cpmux.cmx_fcr & 
> ~CFG_CMXFCR_MASK) |
> (gdb) step
> 221         immr->im_fcc[CONFIG_ETHER_INDEX-1].fcc_fpsmr = CFG_FCC_PSMR | 
> FCC_PSMR_ENCRC;
> (gdb) step
> 227         rxIdx = 0;
> (gdb) step
> 201         volatile cpm8260_t *cp = &(immr->im_cpm);
> (gdb) step
> 213         immr->im_cpmux.cmx_fcr = (immr->im_cpmux.cmx_fcr & 
> ~CFG_CMXFCR_MASK) |
> (gdb) step
> 228         txIdx = 0;
> (gdb) step
> 213         immr->im_cpmux.cmx_fcr = (immr->im_cpmux.cmx_fcr & 
> ~CFG_CMXFCR_MASK) |
> (gdb)
> 
> As you can see the code appears to jump around aimlessly, though the program
> still appears to run ok. Just to finish off I am able to configure the ram 

Seems to be working perfectly.

Please remember that you are debugging on a C  level,  and  a  single
line  of  C code may result in several / many assembler instructions,
and the optimizer may reorder your statements as it  seems  "optimal"
to him. This is what you are seeing here: GDB cannot undo the effects
of the optimizer, so it does the best it can.


If you don't like this, then have a look at section "Debugging - Tips
and Tricks" in our documentation at
http://www.denx.de/twiki/bin/view/DULG/DebuggingTricks


Note that code size and performance will suffer from such mods.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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