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Re: Issues with dwarf APIs


elfutils-devel@lists.fedorahosted.org is the list for the elfutils libraries.

> Even with information of DW_AT_location we are not able to fetch the 
> location information and dwarf_getlocation_addr() fails, returns 0.

"returns 0" != "fails"

>From libdw.h:

			       A return value of zero means that the
   location list indicated no value is accessible.  */

This is a successful call telling you that there are zero locations to be had.

> In this particular case gdb also fails to print cpu value and instead 
> says the value is optimized out.

They are reporting the same truth: the compiler said that this value was
not available at that PC.  If you read the disassembly and think the value
should in fact be available in some register or memory location at the PC
in question, then you need to pursue a compiler bug report about that.


Thanks,
Roland


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